Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cache quality monitoring update from Thomas Gleixner:
"This update provides a complete rewrite of the Cache Quality
Monitoring (CQM) facility.

The existing CQM support was duct taped into perf with a lot of issues
and the attempts to fix those turned out to be incomplete and
horrible.

After lengthy discussions it was decided to integrate the CQM support
into the Resource Director Technology (RDT) facility, which is the
obvious choise as in hardware CQM is part of RDT. This allowed to add
Memory Bandwidth Monitoring support on top.

As a result the mechanisms for allocating cache/memory bandwidth and
the corresponding monitoring mechanisms are integrated into a single
management facility with a consistent user interface"

* 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
x86/intel_rdt: Turn off most RDT features on Skylake
x86/intel_rdt: Add command line options for resource director technology
x86/intel_rdt: Move special case code for Haswell to a quirk function
x86/intel_rdt: Remove redundant ternary operator on return
x86/intel_rdt/cqm: Improve limbo list processing
x86/intel_rdt/mbm: Fix MBM overflow handler during CPU hotplug
x86/intel_rdt: Modify the intel_pqr_state for better performance
x86/intel_rdt/cqm: Clear the default RMID during hotcpu
x86/intel_rdt: Show bitmask of shareable resource with other executing units
x86/intel_rdt/mbm: Handle counter overflow
x86/intel_rdt/mbm: Add mbm counter initialization
x86/intel_rdt/mbm: Basic counting of MBM events (total and local)
x86/intel_rdt/cqm: Add CPU hotplug support
x86/intel_rdt/cqm: Add sched_in support
x86/intel_rdt: Introduce rdt_enable_key for scheduling
x86/intel_rdt/cqm: Add mount,umount support
x86/intel_rdt/cqm: Add rmdir support
x86/intel_rdt: Separate the ctrl bits from rmdir
x86/intel_rdt/cqm: Add mon_data
x86/intel_rdt: Prepare for RDT monitor data support
...

Documentation/admin-guide/kernel-parameters.rst

···
 	PPT	Parallel port support is enabled.
 	PS2	Appropriate PS/2 support is enabled.
 	RAM	RAM disk support is enabled.
+	RDT	Intel Resource Director Technology.
 	S390	S390 architecture is enabled.
 	SCSI	Appropriate SCSI support is enabled.
 			A lot of drivers have their options described inside

Documentation/admin-guide/kernel-parameters.txt

···
 			Run specified binary instead of /init from the ramdisk,
 			used for early userspace startup. See initrd.
 
+	rdt=		[HW,X86,RDT]
+			Turn on/off individual RDT features. List is:
+			cmt, mbmtotal, mbmlocal, l3cat, l3cdp, l2cat, mba.
+			E.g. to turn on cmt and turn off mba use:
+				rdt=cmt,!mba
+
 	reboot=		[KNL]
 			Format (x86 or x86_64):
 				[w[arm] | c[old] | h[ard] | s[oft] | g[pio]] \

Documentation/x86/intel_rdt_ui.txt

···
 Tony Luck <[e-mail]>
 Vikas Shivappa <[e-mail]>
 
-This feature is enabled by the CONFIG_INTEL_RDT_A Kconfig and the
-X86 /proc/cpuinfo flag bits "rdt", "cat_l3" and "cdp_l3".
+This feature is enabled by the CONFIG_INTEL_RDT Kconfig and the
+X86 /proc/cpuinfo flag bits "rdt", "cqm", "cat_l3" and "cdp_l3".
 
 To use the feature mount the file system:
 
···
 
 "cdp": Enable code/data prioritization in L3 cache allocations.
 
+RDT features are orthogonal. A particular system may support only
+monitoring, only control, or both monitoring and control.
+
+The mount succeeds if either of allocation or monitoring is present, but
+only those files and directories supported by the system will be created.
+For more details on the behavior of the interface during monitoring
+and allocation, see the "Resource alloc and monitor groups" section.
 
 Info directory
 --------------
···
 The 'info' directory contains information about the enabled
 resources. Each resource has its own subdirectory. The subdirectory
 names reflect the resource names.
-Cache resource(L3/L2)  subdirectory contains the following files:
+
+Each subdirectory contains the following files with respect to
+allocation:
+
+Cache resource(L3/L2)  subdirectory contains the following files
+related to allocation:
 
 "num_closids":  	The number of CLOSIDs which are valid for this
 			resource. The kernel uses the smallest number of
···
 "min_cbm_bits": 	The minimum number of consecutive bits which
 			must be set when writing a mask.
 
-Memory bandwitdh(MB) subdirectory contains the following files:
+"shareable_bits":	Bitmask of shareable resource with other executing
+			entities (e.g. I/O). User can use this when
+			setting up exclusive cache partitions. Note that
+			some platforms support devices that have their
+			own settings for cache use which can over-ride
+			these bits.
+
+Memory bandwitdh(MB) subdirectory contains the following files
+with respect to allocation:
 
 "min_bandwidth":	The minimum memory bandwidth percentage which
 			user can request.
···
 			non-linear. This field is purely informational
 			only.
 
-Resource groups
----------------
+If RDT monitoring is available there will be an "L3_MON" directory
+with the following files:
+
+"num_rmids":		The number of RMIDs available. This is the
+			upper bound for how many "CTRL_MON" + "MON"
+			groups can be created.
+
+"mon_features":	Lists the monitoring events if
+			monitoring is enabled for the resource.
+
+"max_threshold_occupancy":
+			Read/write file provides the largest value (in
+			bytes) at which a previously used LLC_occupancy
+			counter can be considered for re-use.
+
+
+Resource alloc and monitor groups
+---------------------------------
+
 Resource groups are represented as directories in the resctrl file
-system. The default group is the root directory. Other groups may be
-created as desired by the system administrator using the "mkdir(1)"
-command, and removed using "rmdir(1)".
+system.  The default group is the root directory which, immediately
+after mounting, owns all the tasks and cpus in the system and can make
+full use of all resources.
 
-There are three files associated with each group:
+On a system with RDT control features additional directories can be
+created in the root directory that specify different amounts of each
+resource (see "schemata" below). The root and these additional top level
+directories are referred to as "CTRL_MON" groups below.
 
-"tasks": A list of tasks that belongs to this group. Tasks can be
-	added to a group by writing the task ID to the "tasks" file
-	(which will automatically remove them from the previous
-	group to which they belonged). New tasks created by fork(2)
-	and clone(2) are added to the same group as their parent.
-	If a pid is not in any sub partition, it is in root partition
-	(i.e. default partition).
+On a system with RDT monitoring the root directory and other top level
+directories contain a directory named "mon_groups" in which additional
+directories can be created to monitor subsets of tasks in the CTRL_MON
+group that is their ancestor. These are called "MON" groups in the rest
+of this document.
 
-"cpus": A bitmask of logical CPUs assigned to this group. Writing
-	a new mask can add/remove CPUs from this group. Added CPUs
-	are removed from their previous group. Removed ones are
-	given to the default (root) group. You cannot remove CPUs
-	from the default group.
+Removing a directory will move all tasks and cpus owned by the group it
+represents to the parent. Removing one of the created CTRL_MON groups
+will automatically remove all MON groups below it.
 
-"cpus_list": One or more CPU ranges of logical CPUs assigned to this
-	     group. Same rules apply like for the "cpus" file.
+All groups contain the following files:
 
-"schemata": A list of all the resources available to this group.
-	Each resource has its own line and format - see below for
-	details.
+"tasks":
+	Reading this file shows the list of all tasks that belong to
+	this group. Writing a task id to the file will add a task to the
+	group. If the group is a CTRL_MON group the task is removed from
+	whichever previous CTRL_MON group owned the task and also from
+	any MON group that owned the task. If the group is a MON group,
+	then the task must already belong to the CTRL_MON parent of this
+	group. The task is removed from any previous MON group.
 
-When a task is running the following rules define which resources
-are available to it:
+
+"cpus":
+	Reading this file shows a bitmask of the logical CPUs owned by
+	this group. Writing a mask to this file will add and remove
+	CPUs to/from this group. As with the tasks file a hierarchy is
+	maintained where MON groups may only include CPUs owned by the
+	parent CTRL_MON group.
+
+
+"cpus_list":
+	Just like "cpus", only using ranges of CPUs instead of bitmasks.
+
+
+When control is enabled all CTRL_MON groups will also contain:
+
+"schemata":
+	A list of all the resources available to this group.
+	Each resource has its own line and format - see below for details.
+
+When monitoring is enabled all MON groups will also contain:
+
+"mon_data":
+	This contains a set of files organized by L3 domain and by
+	RDT event. E.g. on a system with two L3 domains there will
+	be subdirectories "mon_L3_00" and "mon_L3_01".	Each of these
+	directories have one file per event (e.g. "llc_occupancy",
+	"mbm_total_bytes", and "mbm_local_bytes"). In a MON group these
+	files provide a read out of the current value of the event for
+	all tasks in the group. In CTRL_MON groups these files provide
+	the sum for all tasks in the CTRL_MON group and all tasks in
+	MON groups. Please see example section for more details on usage.
+
+Resource allocation rules
+-------------------------
+When a task is running the following rules define which resources are
+available to it:
 
 1) If the task is a member of a non-default group, then the schemata
-for that group is used.
+   for that group is used.
 
 2) Else if the task belongs to the default group, but is running on a
-CPU that is assigned to some specific group, then the schemata for
-the CPU's group is used.
+   CPU that is assigned to some specific group, then the schemata for the
+   CPU's group is used.
 
 3) Otherwise the schemata for the default group is used.
 
+Resource monitoring rules
+-------------------------
+1) If a task is a member of a MON group, or non-default CTRL_MON group
+   then RDT events for the task will be reported in that group.
+
+2) If a task is a member of the default CTRL_MON group, but is running
+   on a CPU that is assigned to some specific group, then the RDT events
+   for the task will be reported in that group.
+
+3) Otherwise RDT events for the task will be reported in the root level
+   "mon_data" group.
+
+
+Notes on cache occupancy monitoring and control
+-----------------------------------------------
+When moving a task from one group to another you should remember that
+this only affects *new* cache allocations by the task. E.g. you may have
+a task in a monitor group showing 3 MB of cache occupancy. If you move
+to a new group and immediately check the occupancy of the old and new
+groups you will likely see that the old group is still showing 3 MB and
+the new group zero. When the task accesses locations still in cache from
+before the move, the h/w does not update any counters. On a busy system
+you will likely see the occupancy in the old group go down as cache lines
+are evicted and re-used while the occupancy in the new group rises as
+the task accesses memory and loads into the cache are counted based on
+membership in the new group.
+
+The same applies to cache allocation control. Moving a task to a group
+with a smaller cache partition will not evict any cache lines. The
+process may continue to use them from the old partition.
+
+Hardware uses CLOSid(Class of service ID) and an RMID(Resource monitoring ID)
+to identify a control group and a monitoring group respectively. Each of
+the resource groups are mapped to these IDs based on the kind of group. The
+number of CLOSid and RMID are limited by the hardware and hence the creation of
+a "CTRL_MON" directory may fail if we run out of either CLOSID or RMID
+and creation of "MON" group may fail if we run out of RMIDs.
+
+max_threshold_occupancy - generic concepts
+------------------------------------------
+
+Note that an RMID once freed may not be immediately available for use as
+the RMID is still tagged the cache lines of the previous user of RMID.
+Hence such RMIDs are placed on limbo list and checked back if the cache
+occupancy has gone down. If there is a time when system has a lot of
+limbo RMIDs but which are not ready to be used, user may see an -EBUSY
+during mkdir.
+
+max_threshold_occupancy is a user configurable value to determine the
+occupancy at which an RMID can be freed.
 
 Schemata files - general concepts
 ---------------------------------
···
 sharing a core will result in both threads being throttled to use the
 low bandwidth.
 
-L3 details (code and data prioritization disabled)
---------------------------------------------------
+L3 schemata file details (code and data prioritization disabled)
+----------------------------------------------------------------
 With CDP disabled the L3 schemata format is:
 
 	L3:<cache_id0>=<cbm>;<cache_id1>=<cbm>;...
 
-L3 details (CDP enabled via mount option to resctrl)
-----------------------------------------------------
+L3 schemata file details (CDP enabled via mount option to resctrl)
+------------------------------------------------------------------
 When CDP is enabled L3 control is split into two separate resources
 so you can specify independent masks for code and data like this:
 
 	L3data:<cache_id0>=<cbm>;<cache_id1>=<cbm>;...
 	L3code:<cache_id0>=<cbm>;<cache_id1>=<cbm>;...
 
-L2 details
-----------
+L2 schemata file details
+------------------------
 L2 cache does not support code and data prioritization, so the
 schemata format is always:
 
···
 # cat schemata
 L3DATA:0=fffff;1=fffff;2=3c0;3=fffff
 L3CODE:0=fffff;1=fffff;2=fffff;3=fffff
+
+Examples for RDT allocation usage:
 
 Example 1
 ---------
···
 	/* code to read and write directory contents */
 	resctrl_release_lock(fd);
 }
+
+Examples for RDT Monitoring along with allocation usage:
+
+Reading monitored data
+----------------------
+Reading an event file (for ex: mon_data/mon_L3_00/llc_occupancy) would
+show the current snapshot of LLC occupancy of the corresponding MON
+group or CTRL_MON group.
+
+
+Example 1 (Monitor CTRL_MON group and subset of tasks in CTRL_MON group)
+---------
+On a two socket machine (one L3 cache per socket) with just four bits
+for cache bit masks
+
+# mount -t resctrl resctrl /sys/fs/resctrl
+# cd /sys/fs/resctrl
+# mkdir p0 p1
+# echo "L3:0=3;1=c" > /sys/fs/resctrl/p0/schemata
+# echo "L3:0=3;1=3" > /sys/fs/resctrl/p1/schemata
+# echo 5678 > p1/tasks
+# echo 5679 > p1/tasks
+
+The default resource group is unmodified, so we have access to all parts
+of all caches (its schemata file reads "L3:0=f;1=f").
+
+Tasks that are under the control of group "p0" may only allocate from the
+"lower" 50% on cache ID 0, and the "upper" 50% of cache ID 1.
+Tasks in group "p1" use the "lower" 50% of cache on both sockets.
+
+Create monitor groups and assign a subset of tasks to each monitor group.
+
+# cd /sys/fs/resctrl/p1/mon_groups
+# mkdir m11 m12
+# echo 5678 > m11/tasks
+# echo 5679 > m12/tasks
+
+fetch data (data shown in bytes)
+
+# cat m11/mon_data/mon_L3_00/llc_occupancy
[phone]
+# cat m11/mon_data/mon_L3_01/llc_occupancy
[phone]
+# cat m12/mon_data/mon_L3_00/llc_occupancy
[phone]
+
+The parent ctrl_mon group shows the aggregated data.
+
+# cat /sys/fs/resctrl/p1/mon_data/mon_l3_00/llc_occupancy
[phone]
+
+Example 2 (Monitor a task from its creation)
+---------
+On a two socket machine (one L3 cache per socket)
+
+# mount -t resctrl resctrl /sys/fs/resctrl
+# cd /sys/fs/resctrl
+# mkdir p0 p1
+
+An RMID is allocated to the group once its created and hence the <cmd>
+below is monitored from its creation.
+
+# echo $$ > /sys/fs/resctrl/p1/tasks
+# <cmd>
+
+Fetch the data
+
+# cat /sys/fs/resctrl/p1/mon_data/mon_l3_00/llc_occupancy
[phone]
+
+Example 3 (Monitor without CAT support or before creating CAT groups)
+---------
+
+Assume a system like HSW has only CQM and no CAT support. In this case
+the resctrl will still mount but cannot create CTRL_MON directories.
+But user can create different MON groups within the root group thereby
+able to monitor all tasks including kernel threads.
+
+This can also be used to profile jobs cache size footprint before being
+able to allocate them to different allocation groups.
+
+# mount -t resctrl resctrl /sys/fs/resctrl
+# cd /sys/fs/resctrl
+# mkdir mon_groups/m01
+# mkdir mon_groups/m02
+
+# echo 3478 > /sys/fs/resctrl/mon_groups/m01/tasks
+# echo 2467 > /sys/fs/resctrl/mon_groups/m02/tasks
+
+Monitor the groups separately and also get per domain data. From the
+below its apparent that the tasks are mostly doing work on
+domain(socket) 0.
+
+# cat /sys/fs/resctrl/mon_groups/m01/mon_L3_00/llc_occupancy
[phone]
+# cat /sys/fs/resctrl/mon_groups/m01/mon_L3_01/llc_occupancy
+34555
+# cat /sys/fs/resctrl/mon_groups/m02/mon_L3_00/llc_occupancy
[phone]
+# cat /sys/fs/resctrl/mon_groups/m02/mon_L3_01/llc_occupancy
+32789
+
+
+Example 4 (Monitor real time tasks)
+-----------------------------------
+
+A single socket system which has real time tasks running on cores 4-7
+and non real time tasks on other cpus. We want to monitor the cache
+occupancy of the real time threads on these cores.
+
+# mount -t resctrl resctrl /sys/fs/resctrl
+# cd /sys/fs/resctrl
+# mkdir p1
+
+Move the cpus 4-7 over to p1
+# echo f0 > p0/cpus
+
+View the llc occupancy snapshot
+
+# cat /sys/fs/resctrl/p1/mon_data/mon_L3_00/llc_occupancy
[phone]

MAINTAINERS

···
 L:	[e-mail]
 S:	Supported
 F:	arch/x86/kernel/cpu/intel_rdt*
-F:	arch/x86/include/asm/intel_rdt*
+F:	arch/x86/include/asm/intel_rdt_sched.h
 F:	Documentation/x86/intel_rdt*
 
 READ-COPY UPDATE (RCU)

arch/x86/Kconfig

···
        def_bool y
        depends on X86_GOLDFISH
 
-config INTEL_RDT_A
-	bool "Intel Resource Director Technology Allocation support"
+config INTEL_RDT
+	bool "Intel Resource Director Technology support"
 	default n
 	depends on X86 && CPU_SUP_INTEL
 	select KERNFS
 	help
-	  Select to enable resource allocation which is a sub-feature of
-	  Intel Resource Director Technology(RDT). More information about
-	  RDT can be found in the Intel x86 Architecture Software
-	  Developer Manual.
+	  Select to enable resource allocation and monitoring which are
+	  sub-features of Intel Resource Director Technology(RDT). More
+	  information about RDT can be found in the Intel x86
+	  Architecture Software Developer Manual.
 
 	  Say N if unsure.
 

arch/x86/events/intel/Makefile

···
-obj-$(CONFIG_CPU_SUP_INTEL)		+= core.o bts.o cqm.o
+obj-$(CONFIG_CPU_SUP_INTEL)		+= core.o bts.o
 obj-$(CONFIG_CPU_SUP_INTEL)		+= ds.o knc.o
 obj-$(CONFIG_CPU_SUP_INTEL)		+= lbr.o p4.o p6.o pt.o
 obj-$(CONFIG_PERF_EVENTS_INTEL_RAPL)	+= intel-rapl-perf.o

arch/x86/events/intel/cqm.c

···
-/*
- * Intel Cache Quality-of-Service Monitoring (CQM) support.
- *
- * Based very, very heavily on work by Peter Zijlstra.
- */
-
-#include <linux/perf_event.h>
-#include <linux/slab.h>
-#include <asm/cpu_device_id.h>
-#include <asm/intel_rdt_common.h>
-#include "../perf_event.h"
-
-#define MSR_IA32_QM_CTR		0x0c8e
-#define MSR_IA32_QM_EVTSEL	0x0c8d
-
-#define MBM_CNTR_WIDTH		24
-/*
- * Guaranteed time in ms as per SDM where MBM counters will not overflow.
- */
-#define MBM_CTR_OVERFLOW_TIME	1000
-
-static u32 cqm_max_rmid = -1;
-static unsigned int cqm_l3_scale; /* supposedly cacheline size */
-static bool cqm_enabled, mbm_enabled;
-unsigned int mbm_socket_max;
-
-/*
- * The cached intel_pqr_state is strictly per CPU and can never be
- * updated from a remote CPU. Both functions which modify the state
- * (intel_cqm_event_start and intel_cqm_event_stop) are called with
- * interrupts disabled, which is sufficient for the protection.
- */
-DEFINE_PER_CPU(struct intel_pqr_state, pqr_state);
-static struct hrtimer *mbm_timers;
-/**
- * struct sample - mbm event's (local or total) data
- * @total_bytes    #bytes since we began monitoring
- * @prev_msr       previous value of MSR
- */
-struct sample {
-	u64	total_bytes;
-	u64	prev_msr;
-};
-
-/*
- * samples profiled for total memory bandwidth type events
- */
-static struct sample *mbm_total;
-/*
- * samples profiled for local memory bandwidth type events
- */
-static struct sample *mbm_local;
-
-#define pkg_id	topology_physical_package_id(smp_processor_id())
-/*
- * rmid_2_index returns the index for the rmid in mbm_local/mbm_total array.
- * mbm_total[] and mbm_local[] are linearly indexed by socket# * max number of
- * rmids per socket, an example is given below
- * RMID1 of Socket0:  vrmid =  1
- * RMID1 of Socket1:  vrmid =  1 * (cqm_max_rmid + 1) + 1
- * RMID1 of Socket2:  vrmid =  2 * (cqm_max_rmid + 1) + 1
- */
-#define rmid_2_index(rmid)  ((pkg_id * (cqm_max_rmid + 1)) + rmid)
-/*
- * Protects cache_cgroups and cqm_rmid_free_lru and cqm_rmid_limbo_lru.
- * Also protects event->hw.cqm_rmid
- *
- * Hold either for stability, both for modification of ->hw.cqm_rmid.
- */
-static DEFINE_MUTEX(cache_mutex);
-static DEFINE_RAW_SPINLOCK(cache_lock);
-
-/*
- * Groups of events that have the same target(s), one RMID per group.
- */
-static LIST_HEAD(cache_groups);
-
-/*
- * Mask of CPUs for reading CQM values. We only need one per-socket.
- */
-static cpumask_t cqm_cpumask;
-
-#define RMID_VAL_ERROR		(1ULL << 63)
-#define RMID_VAL_UNAVAIL	(1ULL << 62)
-
-/*
- * Event IDs are used to program IA32_QM_EVTSEL before reading event
- * counter from IA32_QM_CTR
- */
-#define QOS_L3_OCCUP_EVENT_ID	0x01
-#define QOS_MBM_TOTAL_EVENT_ID	0x02
-#define QOS_MBM_LOCAL_EVENT_ID	0x03
-
-/*
- * This is central to the rotation algorithm in __intel_cqm_rmid_rotate().
- *
- * This rmid is always free and is guaranteed to have an associated
- * near-zero occupancy value, i.e. no cachelines are tagged with this
- * RMID, once __intel_cqm_rmid_rotate() returns.
- */
-static u32 intel_cqm_rotation_rmid;
-
-#define INVALID_RMID		(-1)
-
-/*
- * Is @rmid valid for programming the hardware?
- *
- * rmid 0 is reserved by the hardware for all non-monitored tasks, which
- * means that we should never come across an rmid with that value.
- * Likewise, an rmid value of -1 is used to indicate "no rmid currently
- * assigned" and is used as part of the rotation code.
- */
-static inline bool __rmid_valid(u32 rmid)
-{
-	if (!rmid || rmid == INVALID_RMID)
-		return false;
-
-	return true;
-}
-
-static u64 __rmid_read(u32 rmid)
-{
-	u64 val;
-
-	/*
-	 * Ignore the SDM, this thing is _NOTHING_ like a regular perfcnt,
-	 * it just says that to increase confusion.
-	 */
-	wrmsr(MSR_IA32_QM_EVTSEL, QOS_L3_OCCUP_EVENT_ID, rmid);
-	rdmsrl(MSR_IA32_QM_CTR, val);
-
-	/*
-	 * Aside from the ERROR and UNAVAIL bits, assume this thing returns
-	 * the number of cachelines tagged with @rmid.
-	 */
-	return val;
-}
-
-enum rmid_recycle_state {
-	RMID_YOUNG = 0,
-	RMID_AVAILABLE,
-	RMID_DIRTY,
-};
-
-struct cqm_rmid_entry {
-	u32 rmid;
-	enum rmid_recycle_state state;
-	struct list_head list;
-	unsigned long queue_time;
-};
-
-/*
- * cqm_rmid_free_lru - A least recently used list of RMIDs.
- *
- * Oldest entry at the head, newest (most recently used) entry at the
- * tail. This list is never traversed, it's only used to keep track of
- * the lru order. That is, we only pick entries of the head or insert
- * them on the tail.
- *
- * All entries on the list are 'free', and their RMIDs are not currently
- * in use. To mark an RMID as in use, remove its entry from the lru
- * list.
- *
- *
- * cqm_rmid_limbo_lru - list of currently unused but (potentially) dirty RMIDs.
- *
- * This list is contains RMIDs that no one is currently using but that
- * may have a non-zero occupancy value associated with them. The
- * rotation worker moves RMIDs from the limbo list to the free list once
- * the occupancy value drops below __intel_cqm_threshold.
- *
- * Both lists are protected by cache_mutex.
- */
-static LIST_HEAD(cqm_rmid_free_lru);
-static LIST_HEAD(cqm_rmid_limbo_lru);
-
-/*
- * We use a simple array of pointers so that we can lookup a struct
- * cqm_rmid_entry in O(1). This alleviates the callers of __get_rmid()
- * and __put_rmid() from having to worry about dealing with struct
- * cqm_rmid_entry - they just deal with rmids, i.e. integers.
- *
- * Once this array is initialized it is read-only. No locks are required
- * to access it.
- *
- * All entries for all RMIDs can be looked up in the this array at all
- * times.
- */
-static struct cqm_rmid_entry **cqm_rmid_ptrs;
-
-static inline struct cqm_rmid_entry *__rmid_entry(u32 rmid)
-{
-	struct cqm_rmid_entry *entry;
-
-	entry = cqm_rmid_ptrs[rmid];
-	WARN_ON(entry->rmid != rmid);
-
-	return entry;
-}
-
-/*
- * Returns < 0 on fail.
- *
- * We expect to be called with cache_mutex held.
- */
-static u32 __get_rmid(void)
-{
-	struct cqm_rmid_entry *entry;
-
-	lockdep_assert_held(&cache_mutex);
-
-	if (list_empty(&cqm_rmid_free_lru))
-		return INVALID_RMID;
-
-	entry = list_first_entry(&cqm_rmid_free_lru, struct cqm_rmid_entry, list);
-	list_del(&entry->list);
-
-	return entry->rmid;
-}
-
-static void __put_rmid(u32 rmid)
-{
-	struct cqm_rmid_entry *entry;
-
-	lockdep_assert_held(&cache_mutex);
-
-	WARN_ON(!__rmid_valid(rmid));
-	entry = __rmid_entry(rmid);
-
-	entry->queue_time = jiffies;
-	entry->state = RMID_YOUNG;
-
-	list_add_tail(&entry->list, &cqm_rmid_limbo_lru);
-}
-
-static void cqm_cleanup(void)
-{
-	int i;
-
-	if (!cqm_rmid_ptrs)
-		return;
-
-	for (i = 0; i < cqm_max_rmid; i++)
-		kfree(cqm_rmid_ptrs[i]);
-
-	kfree(cqm_rmid_ptrs);
-	cqm_rmid_ptrs = NULL;
-	cqm_enabled = false;
-}
-
-static int intel_cqm_setup_rmid_cache(void)
-{
-	struct cqm_rmid_entry *entry;
-	unsigned int nr_rmids;
-	int r = 0;
-
-	nr_rmids = cqm_max_rmid + 1;
-	cqm_rmid_ptrs = kzalloc(sizeof(struct cqm_rmid_entry *) *
-				nr_rmids, GFP_KERNEL);
-	if (!cqm_rmid_ptrs)
-		return -ENOMEM;
-
-	for (; r <= cqm_max_rmid; r++) {
-		struct cqm_rmid_entry *entry;
-
-		entry = kmalloc(sizeof(*entry), GFP_KERNEL);
-		if (!entry)
-			goto fail;
-
-		INIT_LIST_HEAD(&entry->list);
-		entry->rmid = r;
-		cqm_rmid_ptrs[r] = entry;
-
-		list_add_tail(&entry->list, &cqm_rmid_free_lru);
-	}
-
-	/*
-	 * RMID 0 is special and is always allocated. It's used for all
-	 * tasks that are not monitored.
-	 */
-	entry = __rmid_entry(0);
-	list_del(&entry->list);
-
-	mutex_lock(&cache_mutex);
-	intel_cqm_rotation_rmid = __get_rmid();
-	mutex_unlock(&cache_mutex);
-
-	return 0;
-
-fail:
-	cqm_cleanup();
-	return -ENOMEM;
-}
-
-/*
- * Determine if @a and @b measure the same set of tasks.
- *
- * If @a and @b measure the same set of tasks then we want to share a
- * single RMID.
- */
-static bool __match_event(struct perf_event *a, struct perf_event *b)
-{
-	/* Per-cpu and task events don't mix */
-	if ((a->attach_state & PERF_ATTACH_TASK) !=
-	    (b->attach_state & PERF_ATTACH_TASK))
-		return false;
-
-#ifdef CONFIG_CGROUP_PERF
-	if (a->cgrp != b->cgrp)
-		return false;
-#endif
-
-	/* If not task event, we're machine wide */
-	if (!(b->attach_state & PERF_ATTACH_TASK))
-		return true;
-
-	/*
-	 * Events that target same task are placed into the same cache group.
-	 * Mark it as a multi event group, so that we update ->count
-	 * for every event rather than just the group leader later.
-	 */
-	if (a->hw.target == b->hw.target) {
-		b->hw.is_group_event = true;
-		return true;
-	}
-
-	/*
-	 * Are we an inherited event?
-	 */
-	if (b->parent == a)
-		return true;
-
-	return false;
-}
-
-#ifdef CONFIG_CGROUP_PERF
-static inline struct perf_cgroup *event_to_cgroup(struct perf_event *event)
-{
-	if (event->attach_state & PERF_ATTACH_TASK)
-		return perf_cgroup_from_task(event->hw.target, event->ctx);
-
-	return event->cgrp;
-}
-#endif
-
-/*
- * Determine if @a's tasks intersect with @b's tasks
- *
- * There are combinations of events that we explicitly prohibit,
- *
- *		   PROHIBITS
- *     system-wide    -> 	cgroup and task
- *     cgroup 	      ->	system-wide
- *     		      ->	task in cgroup
- *     task 	      -> 	system-wide
- *     		      ->	task in cgroup
- *
- * Call this function before allocating an RMID.
- */
-static bool __conflict_event(struct perf_event *a, struct perf_event *b)
-{
-#ifdef CONFIG_CGROUP_PERF
-	/*
-	 * We can have any number of cgroups but only one system-wide
-	 * event at a time.
-	 */
-	if (a->cgrp && b->cgrp) {
-		struct perf_cgroup *ac = a->cgrp;
-		struct perf_cgroup *bc = b->cgrp;
-
-		/*
-		 * This condition should have been caught in
-		 * __match_event() and we should be sharing an RMID.
-		 */
-		WARN_ON_ONCE(ac == bc);
-
-		if (cgroup_is_descendant(ac->css.cgroup, bc->css.cgroup) ||
-		    cgroup_is_descendant(bc->css.cgroup, ac->css.cgroup))
-			return true;
-
-		return false;
-	}
-
-	if (a->cgrp || b->cgrp) {
-		struct perf_cgroup *ac, *bc;
-
-		/*
-		 * cgroup and system-wide events are mutually exclusive
-		 */
-		if ((a->cgrp && !(b->attach_state & PERF_ATTACH_TASK)) ||
-		    (b->cgrp && !(a->attach_state & PERF_ATTACH_TASK)))
-			return true;
-
-		/*
-		 * Ensure neither event is part of the other's cgroup
-		 */
-		ac = event_to_cgroup(a);
-		bc = event_to_cgroup(b);
-		if (ac == bc)
-			return true;
-
-		/*
-		 * Must have cgroup and non-intersecting task events.
-		 */
-		if (!ac || !bc)
-			return false;
-
-		/*
-		 * We have cgroup and task events, and the task belongs
-		 * to a cgroup. Check for for overlap.
-		 */
-		if (cgroup_is_descendant(ac->css.cgroup, bc->css.cgroup) ||
-		    cgroup_is_descendant(bc->css.cgroup, ac->css.cgroup))
-			return true;
-
-		return false;
-	}
-#endif
-	/*
-	 * If one of them is not a task, same story as above with cgroups.
-	 */
-	if (!(a->attach_state & PERF_ATTACH_TASK) ||
-	    !(b->attach_state & PERF_ATTACH_TASK))
-		return true;
-
-	/*
-	 * Must be non-overlapping.
-	 */
-	return false;
-}
-
-struct rmid_read {
-	u32 rmid;
-	u32 evt_type;
-	atomic64_t value;
-};
-
-static void __intel_cqm_event_count(void *info);
-static void init_mbm_sample(u32 rmid, u32 evt_type);
-static void __intel_mbm_event_count(void *info);
-
-static bool is_cqm_event(int e)
-{
-	return (e == QOS_L3_OCCUP_EVENT_ID);
-}
-
-static bool is_mbm_event(int e)
-{
-	return (e >= QOS_MBM_TOTAL_EVENT_ID && e <= QOS_MBM_LOCAL_EVENT_ID);
-}
-
-static void cqm_mask_call(struct rmid_read *rr)
-{
-	if (is_mbm_event(rr->evt_type))
-		on_each_cpu_mask(&cqm_cpumask, __intel_mbm_event_count, rr, 1);
-	else
-		on_each_cpu_mask(&cqm_cpumask, __intel_cqm_event_count, rr, 1);
-}
-
-/*
- * Exchange the RMID of a group of events.
- */
-static u32 intel_cqm_xchg_rmid(struct perf_event *group, u32 rmid)
-{
-	struct perf_event *event;
-	struct list_head *head = &group->hw.cqm_group_entry;
-	u32 old_rmid = group->hw.cqm_rmid;
-
-	lockdep_assert_held(&cache_mutex);
-
-	/*
-	 * If our RMID is being deallocated, perform a read now.
-	 */
-	if (__rmid_valid(old_rmid) && !__rmid_valid(rmid)) {
-		struct rmid_read rr = {
-			.rmid = old_rmid,
-			.evt_type = group->attr.config,
-			.value = ATOMIC64_INIT(0),
-		};
-
-		cqm_mask_call(&rr);
-		local64_set(&group->count, atomic64_read(&rr.value));
-	}
-
-	raw_spin_lock_irq(&cache_lock);
-
-	group->hw.cqm_rmid = rmid;
-	list_for_each_entry(event, head, hw.cqm_group_entry)
-		event->hw.cqm_rmid = rmid;
-
-	raw_spin_unlock_irq(&cache_lock);
-
-	/*
-	 * If the allocation is for mbm, init the mbm stats.
-	 * Need to check if each event in the group is mbm event
-	 * because there could be multiple type of events in the same group.
-	 */
-	if (__rmid_valid(rmid)) {
-		event = group;
-		if (is_mbm_event(event->attr.config))
-			init_mbm_sample(rmid, event->attr.config);
-
-		list_for_each_entry(event, head, hw.cqm_group_entry) {
-			if (is_mbm_event(event->attr.config))
-				init_mbm_sample(rmid, event->attr.config);
-		}
-	}
-
-	return old_rmid;
-}
-
-/*
- * If we fail to assign a new RMID for intel_cqm_rotation_rmid because
- * cachelines are still tagged with RMIDs in limbo, we progressively
- * increment the threshold until we find an RMID in limbo with <=
- * __intel_cqm_threshold lines tagged. This is designed to mitigate the
- * problem where cachelines tagged with an RMID are not steadily being
- * evicted.
- *
- * On successful rotations we decrease the threshold back towards zero.
- *
- * __intel_cqm_max_threshold provides an upper bound on the threshold,
- * and is measured in bytes because it's exposed to userland.
- */
-static unsigned int __intel_cqm_threshold;
-static unsigned int __intel_cqm_max_threshold;
-
-/*
- * Test whether an RMID has a zero occupancy value on this cpu.
- */
-static void intel_cqm_stable(void *arg)
-{
-	struct cqm_rmid_entry *entry;
-
-	list_for_each_entry(entry, &cqm_rmid_limbo_lru, list) {
-		if (entry->state != RMID_AVAILABLE)
-			break;
-
-		if (__rmid_read(entry->rmid) > __intel_cqm_threshold)
-			entry->state = RMID_DIRTY;
-	}
-}
-
-/*
- * If we have group events waiting for an RMID that don't conflict with
- * events already running, assign @rmid.
- */
-static bool intel_cqm_sched_in_event(u32 rmid)
-{
-	struct perf_event *leader, *event;
-
-	lockdep_assert_held(&cache_mutex);
-
-	leader = list_first_entry(&cache_groups, struct perf_event,
-				  hw.cqm_groups_entry);
-	event = leader;
-
-	list_for_each_entry_continue(event, &cache_groups,
-				     hw.cqm_groups_entry) {
-		if (__rmid_valid(event->hw.cqm_rmid))
-			continue;
-
-		if (__conflict_event(event, leader))
-			continue;
-
-		intel_cqm_xchg_rmid(event, rmid);
-		return true;
-	}
-
-	return false;
-}
-
-/*
- * Initially use this constant for both the limbo queue time and the
- * rotation timer interval, pmu::hrtimer_interval_ms.
- *
- * They don't need to be the same, but the two are related since if you
- * rotate faster than you recycle RMIDs, you may run out of available
- * RMIDs.
- */
-#define RMID_DEFAULT_QUEUE_TIME 250	/* ms */
-
-static unsigned int __rmid_queue_time_ms = RMID_DEFAULT_QUEUE_TIME;
-
-/*
- * intel_cqm_rmid_stabilize - move RMIDs from limbo to free list
- * @nr_available: number of freeable RMIDs on the limbo list
- *
- * Quiescent state; wait for all 'freed' RMIDs to become unused, i.e. no
- * cachelines are tagged with those RMIDs. After this we can reuse them
- * and know that the current set of active RMIDs is stable.
- *
- * Return %true or %false depending on whether stabilization needs to be
- * reattempted.
- *
- * If we return %true then @nr_available is updated to indicate the
- * number of RMIDs on the limbo list that have been queued for the
- * minimum queue time (RMID_AVAILABLE), but whose data occupancy values
- * are above __intel_cqm_threshold.
- */
-static bool intel_cqm_rmid_stabilize(unsigned int *available)
-{
-	struct cqm_rmid_entry *entry, *tmp;
-
-	lockdep_assert_held(&cache_mutex);
-
-	*available = 0;
-	list_for_each_entry(entry, &cqm_rmid_limbo_lru, list) {
-		unsigned long min_queue_time;
-		unsigned long now = jiffies;
-
-		/*
-		 * We hold RMIDs placed into limbo for a minimum queue
-		 * time. Before the minimum queue time has elapsed we do
-		 * not recycle RMIDs.
-		 *
-		 * The reasoning is that until a sufficient time has
-		 * passed since we stopped using an RMID, any RMID
-		 * placed onto the limbo list will likely still have
-		 * data tagged in the cache, which means we'll probably
-		 * fail to recycle it anyway.
-		 *
-		 * We can save ourselves an expensive IPI by skipping
-		 * any RMIDs that have not been queued for the minimum
-		 * time.
-		 */
-		min_queue_time = entry->queue_time +
-			msecs_to_jiffies(__rmid_queue_time_ms);
-
-		if (time_after(min_queue_time, now))
-			break;
-
-		entry->state = RMID_AVAILABLE;
-		(*available)++;
-	}
-
-	/*
-	 * Fast return if none of the RMIDs on the limbo list have been
-	 * sitting on the queue for the minimum queue time.
-	 */
-	if (!*available)
-		return false;
-
-	/*
-	 * Test whether an RMID is free for each package.
-	 */
-	on_each_cpu_mask(&cqm_cpumask, intel_cqm_stable, NULL, true);
-
-	list_for_each_entry_safe(entry, tmp, &cqm_rmid_limbo_lru, list) {
-		/*
-		 * Exhausted all RMIDs that have waited min queue time.
-		 */
-		if (entry->state == RMID_YOUNG)
-			break;
-
-		if (entry->state == RMID_DIRTY)
-			continue;
-
-		list_del(&entry->list);	/* remove from limbo */
-
-		/*
-		 * The rotation RMID gets priority if it's
-		 * currently invalid. In which case, skip adding
-		 * the RMID to the the free lru.
-		 */
-		if (!__rmid_valid(intel_cqm_rotation_rmid)) {
-			intel_cqm_rotation_rmid = entry->rmid;
-			continue;
-		}
-
-		/*
-		 * If we have groups waiting for RMIDs, hand
-		 * them one now provided they don't conflict.
-		 */
-		if (intel_cqm_sched_in_event(entry->rmid))
-			continue;
-
-		/*
-		 * Otherwise place it onto the free list.
-		 */
-		list_add_tail(&entry->list, &cqm_rmid_free_lru);
-	}
-
-
-	return __rmid_valid(intel_cqm_rotation_rmid);
-}
-
-/*
- * Pick a victim group and move it to the tail of the group list.
- * @next: The first group without an RMID
- */
-static void __intel_cqm_pick_and_rotate(struct perf_event *next)
-{
-	struct perf_event *rotor;
-	u32 rmid;
-
-	lockdep_assert_held(&cache_mutex);
-
-	rotor = list_first_entry(&cache_groups, struct perf_event,
-				 hw.cqm_groups_entry);
-
-	/*
-	 * The group at the front of the list should always have a valid
-	 * RMID. If it doesn't then no groups have RMIDs assigned and we
-	 * don't need to rotate the list.
-	 */
-	if (next == rotor)
-		return;
-
-	rmid = intel_cqm_xchg_rmid(rotor, INVALID_RMID);
-	__put_rmid(rmid);
-
-	list_rotate_left(&cache_groups);
-}
-
-/*
- * Deallocate the RMIDs from any events that conflict with @event, and
- * place them on the back of the group list.
- */
-static void intel_cqm_sched_out_conflicting_events(struct perf_event *event)
-{
-	struct perf_event *group, *g;
-	u32 rmid;
-
-	lockdep_assert_held(&cache_mutex);
-
-	list_for_each_entry_safe(group, g, &cache_groups, hw.cqm_groups_entry) {
-		if (group == event)
-			continue;
-
-		rmid = group->hw.cqm_rmid;
-
-		/*
-		 * Skip events that don't have a valid RMID.
-		 */
-		if (!__rmid_valid(rmid))
-			continue;
-
-		/*
-		 * No conflict? No problem! Leave the event alone.
-		 */
-		if (!__conflict_event(group, event))
-			continue;
-
-		intel_cqm_xchg_rmid(group, INVALID_RMID);
-		__put_rmid(rmid);
-	}
-}
-
-/*
- * Attempt to rotate the groups and assign new RMIDs.
- *
- * We rotate for two reasons,
- *   1. To handle the scheduling of conflicting events
- *   2. To recycle RMIDs
- *
- * Rotating RMIDs is complicated because the hardware doesn't give us
- * any clues.
- *
- * There's problems with the hardware interface; when you change the
- * task:RMID map cachelines retain their 'old' tags, giving a skewed
- * picture. In order to work around this, we must always keep one free
- * RMID - intel_cqm_rotation_rmid.
- *
- * Rotation works by taking away an RMID from a group (the old RMID),
- * and assigning the free RMID to another group (the new RMID). We must
- * then wait for the old RMID to not be used (no cachelines tagged).
- * This ensure that all cachelines are tagged with 'active' RMIDs. At
- * this point we can start reading values for the new RMID and treat the
- * old RMID as the free RMID for the next rotation.
- *
- * Return %true or %false depending on whether we did any rotating.
- */
-static bool __intel_cqm_rmid_rotate(void)
-{
-	struct perf_event *group, *start = NULL;
-	unsigned int threshold_limit;
-	unsigned int nr_needed = 0;
-	unsigned int nr_available;
-	bool rotated = false;
-
-	mutex_lock(&cache_mutex);
-
-again:
-	/*
-	 * Fast path through this function if there are no groups and no
-	 * RMIDs that need cleaning.
-	 */
-	if (list_empty(&cache_groups) && list_empty(&cqm_rmid_limbo_lru))
-		goto out;
-
-	list_for_each_entry(group, &cache_groups, hw.cqm_groups_entry) {
-		if (!__rmid_valid(group->hw.cqm_rmid)) {
-			if (!start)
-				start = group;
-			nr_needed++;
-		}
-	}
-
-	/*
-	 * We have some event groups, but they all have RMIDs assigned
-	 * and no RMIDs need cleaning.
-	 */
-	if (!nr_needed && list_empty(&cqm_rmid_limbo_lru))
-		goto out;
-
-	if (!nr_needed)
-		goto stabilize;
-
-	/*
-	 * We have more event groups without RMIDs than available RMIDs,
-	 * or we have event groups that conflict with the ones currently
-	 * scheduled.
-	 *
-	 * We force deallocate the rmid of the group at the head of
-	 * cache_groups. The first event group without an RMID then gets
-	 * assigned intel_cqm_rotation_rmid. This ensures we always make
-	 * forward progress.
-	 *
-	 * Rotate the cache_groups list so the previous head is now the
-	 * tail.
-	 */
-	__intel_cqm_pick_and_rotate(start);
-
-	/*
-	 * If the rotation is going to succeed, reduce the threshold so
-	 * that we don't needlessly reuse dirty RMIDs.
-	 */
-	if (__rmid_valid(intel_cqm_rotation_rmid)) {
-		intel_cqm_xchg_rmid(start, intel_cqm_rotation_rmid);
-		intel_cqm_rotation_rmid = __get_rmid();
-
-		intel_cqm_sched_out_conflicting_events(start);
-
-		if (__intel_cqm_threshold)
-			__intel_cqm_threshold--;
-	}
-
-	rotated = true;
-
-stabilize:
-	/*
-	 * We now need to stablize the RMID we freed above (if any) to
-	 * ensure that the next time we rotate we have an RMID with zero
-	 * occupancy value.
-	 *
-	 * Alternatively, if we didn't need to perform any rotation,
-	 * we'll have a bunch of RMIDs in limbo that need stabilizing.
-	 */
-	threshold_limit = __intel_cqm_max_threshold / cqm_l3_scale;
-
-	while (intel_cqm_rmid_stabilize(&nr_available) &&
-	       __intel_cqm_threshold < threshold_limit) {
-		unsigned int steal_limit;
-
-		/*
-		 * Don't spin if nobody is actively waiting for an RMID,
-		 * the rotation worker will be kicked as soon as an
-		 * event needs an RMID anyway.
-		 */
-		if (!nr_needed)
-			break;
-
-		/* Allow max 25% of RMIDs to be in limbo. */
-		steal_limit = (cqm_max_rmid + 1) / 4;
-
-		/*
-		 * We failed to stabilize any RMIDs so our rotation
-		 * logic is now stuck. In order to make forward progress
-		 * we have a few options:
-		 *
-		 *   1. rotate ("steal") another RMID
-		 *   2. increase the threshold
-		 *   3. do nothing
-		 *
-		 * We do both of 1. and 2. until we hit the steal limit.
-		 *
-		 * The steal limit prevents all RMIDs ending up on the
-		 * limbo list. This can happen if every RMID has a
-		 * non-zero occupancy above threshold_limit, and the
-		 * occupancy values aren't dropping fast enough.
-		 *
-		 * Note that there is prioritisation at work here - we'd
-		 * rather increase the number of RMIDs on the limbo list
-		 * than increase the threshold, because increasing the
-		 * threshold skews the event data (because we reuse
-		 * dirty RMIDs) - threshold bumps are a last resort.
-		 */
-		if (nr_available < steal_limit)
-			goto again;
-
-		__intel_cqm_threshold++;
-	}
-
-out:
-	mutex_unlock(&cache_mutex);
-	return rotated;
-}
-
-static void intel_cqm_rmid_rotate(struct work_struct *work);
-
-static DECLARE_DELAYED_WORK(intel_cqm_rmid_work, intel_cqm_rmid_rotate);
-
-static struct pmu intel_cqm_pmu;
-
-static void intel_cqm_rmid_rotate(struct work_struct *work)
-{
-	unsigned long delay;
-
-	__intel_cqm_rmid_rotate();
-
-	delay = msecs_to_jiffies(intel_cqm_pmu.hrtimer_interval_ms);
-	schedule_delayed_work(&intel_cqm_rmid_work, delay);
-}
-
-static u64 update_sample(unsigned int rmid, u32 evt_type, int first)
-{
-	struct sample *mbm_current;
-	u32 vrmid = rmid_2_index(rmid);
-	u64 val, bytes, shift;
-	u32 eventid;
-
-	if (evt_type == QOS_MBM_LOCAL_EVENT_ID) {
-		mbm_current = &mbm_local[vrmid];
-		eventid     = QOS_MBM_LOCAL_EVENT_ID;
-	} else {
-		mbm_current = &mbm_total[vrmid];
-		eventid     = QOS_MBM_TOTAL_EVENT_ID;
-	}
-
-	wrmsr(MSR_IA32_QM_EVTSEL, eventid, rmid);
-	rdmsrl(MSR_IA32_QM_CTR, val);
-	if (val & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL))
-		return mbm_current->total_bytes;
-
-	if (first) {
-		mbm_current->prev_msr = val;
-		mbm_current->total_bytes = 0;
-		return mbm_current->total_bytes;
-	}
-
-	/*
-	 * The h/w guarantees that counters will not overflow
-	 * so long as we poll them at least once per second.
-	 */
-	shift = 64 - MBM_CNTR_WIDTH;
-	bytes = (val << shift) - (mbm_current->prev_msr << shift);
-	bytes >>= shift;
-
-	bytes *= cqm_l3_scale;
-
-	mbm_current->total_bytes += bytes;
-	mbm_current->prev_msr = val;
-
-	return mbm_current->total_bytes;
-}
-
-static u64 rmid_read_mbm(unsigned int rmid, u32 evt_type)
-{
-	return update_sample(rmid, evt_type, 0);
-}
-
-static void __intel_mbm_event_init(void *info)
-{
-	struct rmid_read *rr = info;
-
-	update_sample(rr->rmid, rr->evt_type, 1);
-}
-
-static void init_mbm_sample(u32 rmid, u32 evt_type)
-{
-	struct rmid_read rr = {
-		.rmid = rmid,
-		.evt_type = evt_type,
-		.value = ATOMIC64_INIT(0),
-	};
-
-	/* on each socket, init sample */
-	on_each_cpu_mask(&cqm_cpumask, __intel_mbm_event_init, &rr, 1);
-}
-
-/*
- * Find a group and setup RMID.
- *
- * If we're part of a group, we use the group's RMID.
- */
-static void intel_cqm_setup_event(struct perf_event *event,
-				  struct perf_event **group)
-{
-	struct perf_event *iter;
-	bool conflict = false;
-	u32 rmid;
-
-	event->hw.is_group_event = false;
-	list_for_each_entry(iter, &cache_groups, hw.cqm_groups_entry) {
-		rmid = iter->hw.cqm_rmid;
-
-		if (__match_event(iter, event)) {
-			/* All tasks in a group share an RMID */
-			event->hw.cqm_rmid = rmid;
-			*group = iter;
-			if (is_mbm_event(event->attr.config) && __rmid_valid(rmid))
-				init_mbm_sample(rmid, event->attr.config);
-			return;
-		}
-
-		/*
-		 * We only care about conflicts for events that are
-		 * actually scheduled in (and hence have a valid RMID).
-		 */
-		if (__conflict_event(iter, event) && __rmid_valid(rmid))
-			conflict = true;
-	}
-
-	if (conflict)
-		rmid = INVALID_RMID;
-	else
-		rmid = __get_rmid();
-
-	if (is_mbm_event(event->attr.config) && __rmid_valid(rmid))
-		init_mbm_sample(rmid, event->attr.config);
-
-	event->hw.cqm_rmid = rmid;
-}
-
-static void intel_cqm_event_read(struct perf_event *event)
-{
-	unsigned long flags;
-	u32 rmid;
-	u64 val;
-
-	/*
-	 * Task events are handled by intel_cqm_event_count().
-	 */
-	if (event->cpu == -1)
-		return;
-
-	raw_spin_lock_irqsave(&cache_lock, flags);
-	rmid = event->hw.cqm_rmid;
-
-	if (!__rmid_valid(rmid))
-		goto out;
-
-	if (is_mbm_event(event->attr.config))
-		val = rmid_read_mbm(rmid, event->attr.config);
-	else
-		val = __rmid_read(rmid);
-
-	/*
-	 * Ignore this reading on error states and do not update the value.
-	 */
-	if (val & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL))
-		goto out;
-
-	local64_set(&event->count, val);
-out:
-	raw_spin_unlock_irqrestore(&cache_lock, flags);
-}
-
-static void __intel_cqm_event_count(void *info)
-{
-	struct rmid_read *rr = info;
-	u64 val;
-
-	val = __rmid_read(rr->rmid);
-
-	if (val & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL))
-		return;
-
-	atomic64_add(val, &rr->value);
-}
-
-static inline bool cqm_group_leader(struct perf_event *event)
-{
-	return !list_empty(&event->hw.cqm_groups_entry);
-}
-
-static void __intel_mbm_event_count(void *info)
-{
-	struct rmid_read *rr = info;
-	u64 val;
-
-	val = rmid_read_mbm(rr->rmid, rr->evt_type);
-	if (val & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL))
-		return;
-	atomic64_add(val, &rr->value);
-}
-
-static enum hrtimer_restart mbm_hrtimer_handle(struct hrtimer *hrtimer)
-{
-	struct perf_event *iter, *iter1;
-	int ret = HRTIMER_RESTART;
-	struct list_head *head;
-	unsigned long flags;
-	u32 grp_rmid;
-
-	/*
-	 * Need to cache_lock as the timer Event Select MSR reads
-	 * can race with the mbm/cqm count() and mbm_init() reads.
-	 */
-	raw_spin_lock_irqsave(&cache_lock, flags);
-
-	if (list_empty(&cache_groups)) {
-		ret = HRTIMER_NORESTART;
-		goto out;
-	}
-
-	list_for_each_entry(iter, &cache_groups, hw.cqm_groups_entry) {
-		grp_rmid = iter->hw.cqm_rmid;
-		if (!__rmid_valid(grp_rmid))
-			continue;
-		if (is_mbm_event(iter->attr.config))
-			update_sample(grp_rmid, iter->attr.config, 0);
-
-		head = &iter->hw.cqm_group_entry;
-		if (list_empty(head))
-			continue;
-		list_for_each_entry(iter1, head, hw.cqm_group_entry) {
-			if (!iter1->hw.is_group_event)
-				break;
-			if (is_mbm_event(iter1->attr.config))
-				update_sample(iter1->hw.cqm_rmid,
-					      iter1->attr.config, 0);
-		}
-	}
-
-	hrtimer_forward_now(hrtimer, ms_to_ktime(MBM_CTR_OVERFLOW_TIME));
-out:
-	raw_spin_unlock_irqrestore(&cache_lock, flags);
-
-	return ret;
-}
-
-static void __mbm_start_timer(void *info)
-{
-	hrtimer_start(&mbm_timers[pkg_id], ms_to_ktime(MBM_CTR_OVERFLOW_TIME),
-			     HRTIMER_MODE_REL_PINNED);
-}
-
-static void __mbm_stop_timer(void *info)
-{
-	hrtimer_cancel(&mbm_timers[pkg_id]);
-}
-
-static void mbm_start_timers(void)
-{
-	on_each_cpu_mask(&cqm_cpumask, __mbm_start_timer, NULL, 1);
-}
-
-static void mbm_stop_timers(void)
-{
-	on_each_cpu_mask(&cqm_cpumask, __mbm_stop_timer, NULL, 1);
-}
-
-static void mbm_hrtimer_init(void)
-{
-	struct hrtimer *hr;
-	int i;
-
-	for (i = 0; i < mbm_socket_max; i++) {
-		hr = &mbm_timers[i];
-		hrtimer_init(hr, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-		hr->function = mbm_hrtimer_handle;
-	}
-}
-
-static u64 intel_cqm_event_count(struct perf_event *event)
-{
-	unsigned long flags;
-	struct rmid_read rr = {
-		.evt_type = event->attr.config,
-		.value = ATOMIC64_INIT(0),
-	};
-
-	/*
-	 * We only need to worry about task events. System-wide events
-	 * are handled like usual, i.e. entirely with
-	 * intel_cqm_event_read().
-	 */
-	if (event->cpu != -1)
-		return __perf_event_count(event);
-
-	/*
-	 * Only the group leader gets to report values except in case of
-	 * multiple events in the same group, we still need to read the
-	 * other events.This stops us
-	 * reporting duplicate values to userspace, and gives us a clear
-	 * rule for which task gets to report the values.
-	 *
-	 * Note that it is impossible to attribute these values to
-	 * specific packages - we forfeit that ability when we create
-	 * task events.
-	 */
-	if (!cqm_group_leader(event) && !event->hw.is_group_event)
-		return 0;
-
-	/*
-	 * Getting up-to-date values requires an SMP IPI which is not
-	 * possible if we're being called in interrupt context. Return
-	 * the cached values instead.
-	 */
-	if (unlikely(in_interrupt()))
-		goto out;
-
-	/*
-	 * Notice that we don't perform the reading of an RMID
-	 * atomically, because we can't hold a spin lock across the
-	 * IPIs.
-	 *
-	 * Speculatively perform the read, since @event might be
-	 * assigned a different (possibly invalid) RMID while we're
-	 * busying performing the IPI calls. It's therefore necessary to
-	 * check @event's RMID afterwards, and if it has changed,
-	 * discard the result of the read.
-	 */
-	rr.rmid = ACCESS_ONCE(event->hw.cqm_rmid);
-
-	if (!__rmid_valid(rr.rmid))
-		goto out;
-
-	cqm_mask_call(&rr);
-
-	raw_spin_lock_irqsave(&cache_lock, flags);
-	if (event->hw.cqm_rmid == rr.rmid)
-		local64_set(&event->count, atomic64_read(&rr.value));
-	raw_spin_unlock_irqrestore(&cache_lock, flags);
-out:
-	return __perf_event_count(event);
-}
-
-static void intel_cqm_event_start(struct perf_event *event, int mode)
-{
-	struct intel_pqr_state *state = this_cpu_ptr(&pqr_state);
-	u32 rmid = event->hw.cqm_rmid;
-
-	if (!(event->hw.cqm_state & PERF_HES_STOPPED))
-		return;
-
-	event->hw.cqm_state &= ~PERF_HES_STOPPED;
-
-	if (state->rmid_usecnt++) {
-		if (!WARN_ON_ONCE(state->rmid != rmid))
-			return;
-	} else {
-		WARN_ON_ONCE(state->rmid);
-	}
-
-	state->rmid = rmid;
-	wrmsr(MSR_IA32_PQR_ASSOC, rmid, state->closid);
-}
-
-static void intel_cqm_event_stop(struct perf_event *event, int mode)
-{
-	struct intel_pqr_state *state = this_cpu_ptr(&pqr_state);
-
-	if (event->hw.cqm_state & PERF_HES_STOPPED)
-		return;
-
-	event->hw.cqm_state |= PERF_HES_STOPPED;
-
-	intel_cqm_event_read(event);
-
-	if (!--state->rmid_usecnt) {
-		state->rmid = 0;
-		wrmsr(MSR_IA32_PQR_ASSOC, 0, state->closid);
-	} else {
-		WARN_ON_ONCE(!state->rmid);
-	}
-}
-
-static int intel_cqm_event_add(struct perf_event *event, int mode)
-{
-	unsigned long flags;
-	u32 rmid;
-
-	raw_spin_lock_irqsave(&cache_lock, flags);
-
-	event->hw.cqm_state = PERF_HES_STOPPED;
-	rmid = event->hw.cqm_rmid;
-
-	if (__rmid_valid(rmid) && (mode & PERF_EF_START))
-		intel_cqm_event_start(event, mode);
-
-	raw_spin_unlock_irqrestore(&cache_lock, flags);
-
-	return 0;
-}
-
-static void intel_cqm_event_destroy(struct perf_event *event)
-{
-	struct perf_event *group_other = NULL;
-	unsigned long flags;
-
-	mutex_lock(&cache_mutex);
-	/*
-	* Hold the cache_lock as mbm timer handlers could be
-	* scanning the list of events.
-	*/
-	raw_spin_lock_irqsave(&cache_lock, flags);
-
-	/*
-	 * If there's another event in this group...
-	 */
-	if (!list_empty(&event->hw.cqm_group_entry)) {
-		group_other = list_first_entry(&event->hw.cqm_group_entry,
-					       struct perf_event,
-					       hw.cqm_group_entry);
-		list_del(&event->hw.cqm_group_entry);
-	}
-
-	/*
-	 * And we're the group leader..
-	 */
-	if (cqm_group_leader(event)) {
-		/*
-		 * If there was a group_other, make that leader, otherwise
-		 * destroy the group and return the RMID.
-		 */
-		if (group_other) {
-			list_replace(&event->hw.cqm_groups_entry,
-				     &group_other->hw.cqm_groups_entry);
-		} else {
-			u32 rmid = event->hw.cqm_rmid;
-
-			if (__rmid_valid(rmid))
-				__put_rmid(rmid);
-			list_del(&event->hw.cqm_groups_entry);
-		}
-	}
-
-	raw_spin_unlock_irqrestore(&cache_lock, flags);
-
-	/*
-	 * Stop the mbm overflow timers when the last event is destroyed.
-	*/
-	if (mbm_enabled && list_empty(&cache_groups))
-		mbm_stop_timers();
-
-	mutex_unlock(&cache_mutex);
-}
-
-static int intel_cqm_event_init(struct perf_event *event)
-{
-	struct perf_event *group = NULL;
-	bool rotate = false;
-	unsigned long flags;
-
-	if (event->attr.type != intel_cqm_pmu.type)
-		return -ENOENT;
-
-	if ((event->attr.config < QOS_L3_OCCUP_EVENT_ID) ||
-	     (event->attr.config > QOS_MBM_LOCAL_EVENT_ID))
-		return -EINVAL;
-
-	if ((is_cqm_event(event->attr.config) && !cqm_enabled) ||
-	    (is_mbm_event(event->attr.config) && !mbm_enabled))
-		return -EINVAL;
-
-	/* unsupported modes and filters */
-	if (event->attr.exclude_user   ||
-	    event->attr.exclude_kernel ||
-	    event->attr.exclude_hv     ||
-	    event->attr.exclude_idle   ||
-	    event->attr.exclude_host   ||
-	    event->attr.exclude_guest  ||
-	    event->attr.sample_period) /* no sampling */
-		return -EINVAL;
-
-	INIT_LIST_HEAD(&event->hw.cqm_group_entry);
-	INIT_LIST_HEAD(&event->hw.cqm_groups_entry);
-
-	event->destroy = intel_cqm_event_destroy;
-
-	mutex_lock(&cache_mutex);
-
-	/*
-	 * Start the mbm overflow timers when the first event is created.
-	*/
-	if (mbm_enabled && list_empty(&cache_groups))
-		mbm_start_timers();
-
-	/* Will also set rmid */
-	intel_cqm_setup_event(event, &group);
-
-	/*
-	* Hold the cache_lock as mbm timer handlers be
-	* scanning the list of events.
-	*/
-	raw_spin_lock_irqsave(&cache_lock, flags);
-
-	if (group) {
-		list_add_tail(&event->hw.cqm_group_entry,
-			      &group->hw.cqm_group_entry);
-	} else {
-		list_add_tail(&event->hw.cqm_groups_entry,
-			      &cache_groups);
-
-		/*
-		 * All RMIDs are either in use or have recently been
-		 * used. Kick the rotation worker to clean/free some.
-		 *
-		 * We only do this for the group leader, rather than for
-		 * every event in a group to save on needless work.
-		 */
-		if (!__rmid_valid(event->hw.cqm_rmid))
-			rotate = true;
-	}
-
-	raw_spin_unlock_irqrestore(&cache_lock, flags);
-	mutex_unlock(&cache_mutex);
-
-	if (rotate)
-		schedule_delayed_work(&intel_cqm_rmid_work, 0);
-
-	return 0;
-}
-
-EVENT_ATTR_STR(llc_occupancy, intel_cqm_llc, "event=0x01");
-EVENT_ATTR_STR(llc_occupancy.per-pkg, intel_cqm_llc_pkg, "1");
-EVENT_ATTR_STR(llc_occupancy.unit, intel_cqm_llc_unit, "Bytes");
-EVENT_ATTR_STR(llc_occupancy.scale, intel_cqm_llc_scale, NULL);
-EVENT_ATTR_STR(llc_occupancy.snapshot, intel_cqm_llc_snapshot, "1");
-
-EVENT_ATTR_STR(total_bytes, intel_cqm_total_bytes, "event=0x02");
-EVENT_ATTR_STR(total_bytes.per-pkg, intel_cqm_total_bytes_pkg, "1");
-EVENT_ATTR_STR(total_bytes.unit, intel_cqm_total_bytes_unit, "MB");
-EVENT_ATTR_STR(total_bytes.scale, intel_cqm_total_bytes_scale, "1e-6");
-
-EVENT_ATTR_STR(local_bytes, intel_cqm_local_bytes, "event=0x03");
-EVENT_ATTR_STR(local_bytes.per-pkg, intel_cqm_local_bytes_pkg, "1");
-EVENT_ATTR_STR(local_bytes.unit, intel_cqm_local_bytes_unit, "MB");
-EVENT_ATTR_STR(local_bytes.scale, intel_cqm_local_bytes_scale, "1e-6");
-
-static struct attribute *intel_cqm_events_attr[] = {
-	EVENT_PTR(intel_cqm_llc),
-	EVENT_PTR(intel_cqm_llc_pkg),
-	EVENT_PTR(intel_cqm_llc_unit),
-	EVENT_PTR(intel_cqm_llc_scale),
-	EVENT_PTR(intel_cqm_llc_snapshot),
-	NULL,
-};
-
-static struct attribute *intel_mbm_events_attr[] = {
-	EVENT_PTR(intel_cqm_total_bytes),
-	EVENT_PTR(intel_cqm_local_bytes),
-	EVENT_PTR(intel_cqm_total_bytes_pkg),
-	EVENT_PTR(intel_cqm_local_bytes_pkg),
-	EVENT_PTR(intel_cqm_total_bytes_unit),
-	EVENT_PTR(intel_cqm_local_bytes_unit),
-	EVENT_PTR(intel_cqm_total_bytes_scale),
-	EVENT_PTR(intel_cqm_local_bytes_scale),
-	NULL,
-};
-
-static struct attribute *intel_cmt_mbm_events_attr[] = {
-	EVENT_PTR(intel_cqm_llc),
-	EVENT_PTR(intel_cqm_total_bytes),
-	EVENT_PTR(intel_cqm_local_bytes),
-	EVENT_PTR(intel_cqm_llc_pkg),
-	EVENT_PTR(intel_cqm_total_bytes_pkg),
-	EVENT_PTR(intel_cqm_local_bytes_pkg),
-	EVENT_PTR(intel_cqm_llc_unit),
-	EVENT_PTR(intel_cqm_total_bytes_unit),
-	EVENT_PTR(intel_cqm_local_bytes_unit),
-	EVENT_PTR(intel_cqm_llc_scale),
-	EVENT_PTR(intel_cqm_total_bytes_scale),
-	EVENT_PTR(intel_cqm_local_bytes_scale),
-	EVENT_PTR(intel_cqm_llc_snapshot),
-	NULL,
-};
-
-static struct attribute_group intel_cqm_events_group = {
-	.name = "events",
-	.attrs = NULL,
-};
-
-PMU_FORMAT_ATTR(event, "config:0-7");
-static struct attribute *intel_cqm_formats_attr[] = {
-	&format_attr_event.attr,
-	NULL,
-};
-
-static struct attribute_group intel_cqm_format_group = {
-	.name = "format",
-	.attrs = intel_cqm_formats_attr,
-};
-
-static ssize_t
-max_recycle_threshold_show(struct device *dev, struct device_attribute *attr,
-			   char *page)
-{
-	ssize_t rv;
-
-	mutex_lock(&cache_mutex);
-	rv = snprintf(page, PAGE_SIZE-1, "%u\n", __intel_cqm_max_threshold);
-	mutex_unlock(&cache_mutex);
-
-	return rv;
-}
-
-static ssize_t
-max_recycle_threshold_store(struct device *dev,
-			    struct device_attribute *attr,
-			    const char *buf, size_t count)
-{
-	unsigned int bytes, cachelines;
-	int ret;
-
-	ret = kstrtouint(buf, 0, &bytes);
-	if (ret)
-		return ret;
-
-	mutex_lock(&cache_mutex);
-
-	__intel_cqm_max_threshold = bytes;
-	cachelines = bytes / cqm_l3_scale;
-
-	/*
-	 * The new maximum takes effect immediately.
-	 */
-	if (__intel_cqm_threshold > cachelines)
-		__intel_cqm_threshold = cachelines;
-
-	mutex_unlock(&cache_mutex);
-
-	return count;
-}
-
-static DEVICE_ATTR_RW(max_recycle_threshold);
-
-static struct attribute *intel_cqm_attrs[] = {
-	&dev_attr_max_recycle_threshold.attr,
-	NULL,
-};
-
-static const struct attribute_group intel_cqm_group = {
-	.attrs = intel_cqm_attrs,
-};
-
-static const struct attribute_group *intel_cqm_attr_groups[] = {
-	&intel_cqm_events_group,
-	&intel_cqm_format_group,
-	&intel_cqm_group,
-	NULL,
-};
-
-static struct pmu intel_cqm_pmu = {
-	.hrtimer_interval_ms = RMID_DEFAULT_QUEUE_TIME,
-	.attr_groups	     = intel_cqm_attr_groups,
-	.task_ctx_nr	     = perf_sw_context,
-	.event_init	     = intel_cqm_event_init,
-	.add		     = intel_cqm_event_add,
-	.del		     = intel_cqm_event_stop,
-	.start		     = intel_cqm_event_start,
-	.stop		     = intel_cqm_event_stop,
-	.read		     = intel_cqm_event_read,
-	.count		     = intel_cqm_event_count,
-};
-
-static inline void cqm_pick_event_reader(int cpu)
-{
-	int reader;
-
-	/* First online cpu in package becomes the reader */
-	reader = cpumask_any_and(&cqm_cpumask, topology_core_cpumask(cpu));
-	if (reader >= nr_cpu_ids)
-		cpumask_set_cpu(cpu, &cqm_cpumask);
-}
-
-static int intel_cqm_cpu_starting(unsigned int cpu)
-{
-	struct intel_pqr_state *state = &per_cpu(pqr_state, cpu);
-	struct cpuinfo_x86 *c = &cpu_data(cpu);
-
-	state->rmid = 0;
-	state->closid = 0;
-	state->rmid_usecnt = 0;
-
-	WARN_ON(c->x86_cache_max_rmid != cqm_max_rmid);
-	WARN_ON(c->x86_cache_occ_scale != cqm_l3_scale);
-
-	cqm_pick_event_reader(cpu);
-	return 0;
-}
-
-static int intel_cqm_cpu_exit(unsigned int cpu)
-{
-	int target;
-
-	/* Is @cpu the current cqm reader for this package ? */
-	if (!cpumask_test_and_clear_cpu(cpu, &cqm_cpumask))
-		return 0;
-
-	/* Find another online reader in this package */
-	target = cpumask_any_but(topology_core_cpumask(cpu), cpu);
-
-	if (target < nr_cpu_ids)
-		cpumask_set_cpu(target, &cqm_cpumask);
-
-	return 0;
-}
-
-static const struct x86_cpu_id intel_cqm_match[] = {
-	{ .vendor = X86_VENDOR_INTEL, .feature = X86_FEATURE_CQM_OCCUP_LLC },
-	{}
-};
-
-static void mbm_cleanup(void)
-{
-	if (!mbm_enabled)
-		return;
-
-	kfree(mbm_local);
-	kfree(mbm_total);
-	mbm_enabled = false;
-}
-
-static const struct x86_cpu_id intel_mbm_local_match[] = {
-	{ .vendor = X86_VENDOR_INTEL, .feature = X86_FEATURE_CQM_MBM_LOCAL },
-	{}
-};
-
-static const struct x86_cpu_id intel_mbm_total_match[] = {
-	{ .vendor = X86_VENDOR_INTEL, .feature = X86_FEATURE_CQM_MBM_TOTAL },
-	{}
-};
-
-static int intel_mbm_init(void)
-{
-	int ret = 0, array_size, maxid = cqm_max_rmid + 1;
-
-	mbm_socket_max = topology_max_packages();
-	array_size = sizeof(struct sample) * maxid * mbm_socket_max;
-	mbm_local = kmalloc(array_size, GFP_KERNEL);
-	if (!mbm_local)
-		return -ENOMEM;
-
-	mbm_total = kmalloc(array_size, GFP_KERNEL);
-	if (!mbm_total) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	array_size = sizeof(struct hrtimer) * mbm_socket_max;
-	mbm_timers = kmalloc(array_size, GFP_KERNEL);
-	if (!mbm_timers) {
-		ret = -ENOMEM;
-		goto out;
-	}
-	mbm_hrtimer_init();
-
-out:
-	if (ret)
-		mbm_cleanup();
-
-	return ret;
-}
-
-static int __init intel_cqm_init(void)
-{
-	char *str = NULL, scale[20];
-	int cpu, ret;
-
-	if (x86_match_cpu(intel_cqm_match))
-		cqm_enabled = true;
-
-	if (x86_match_cpu(intel_mbm_local_match) &&
-	     x86_match_cpu(intel_mbm_total_match))
-		mbm_enabled = true;
-
-	if (!cqm_enabled && !mbm_enabled)
-		return -ENODEV;
-
-	cqm_l3_scale = boot_cpu_data.x86_cache_occ_scale;
-
-	/*
-	 * It's possible that not all resources support the same number
-	 * of RMIDs. Instead of making scheduling much more complicated
-	 * (where we have to match a task's RMID to a cpu that supports
-	 * that many RMIDs) just find the minimum RMIDs supported across
-	 * all cpus.
-	 *
-	 * Also, check that the scales match on all cpus.
-	 */
-	cpus_read_lock();
-	for_each_online_cpu(cpu) {
-		struct cpuinfo_x86 *c = &cpu_data(cpu);
-
-		if (c->x86_cache_max_rmid < cqm_max_rmid)
-			cqm_max_rmid = c->x86_cache_max_rmid;
-
-		if (c->x86_cache_occ_scale != cqm_l3_scale) {
-			pr_err("Multiple LLC scale values, disabling\n");
-			ret = -EINVAL;
-			goto out;
-		}
-	}
-
-	/*
-	 * A reasonable upper limit on the max threshold is the number
-	 * of lines tagged per RMID if all RMIDs have the same number of
-	 * lines tagged in the LLC.
-	 *
-	 * For a 35MB LLC and 56 RMIDs, this is ~1.8% of the LLC.
-	 */
-	__intel_cqm_max_threshold =
-		boot_cpu_data.x86_cache_size * 1024 / (cqm_max_rmid + 1);
-
-	snprintf(scale, sizeof(scale), "%u", cqm_l3_scale);
-	str = kstrdup(scale, GFP_KERNEL);
-	if (!str) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	event_attr_intel_cqm_llc_scale.event_str = str;
-
-	ret = intel_cqm_setup_rmid_cache();
-	if (ret)
-		goto out;
-
-	if (mbm_enabled)
-		ret = intel_mbm_init();
-	if (ret && !cqm_enabled)
-		goto out;
-
-	if (cqm_enabled && mbm_enabled)
-		intel_cqm_events_group.attrs = intel_cmt_mbm_events_attr;
-	else if (!cqm_enabled && mbm_enabled)
-		intel_cqm_events_group.attrs = intel_mbm_events_attr;
-	else if (cqm_enabled && !mbm_enabled)
-		intel_cqm_events_group.attrs = intel_cqm_events_attr;
-
-	ret = perf_pmu_register(&intel_cqm_pmu, "intel_cqm", -1);
-	if (ret) {
-		pr_err("Intel CQM perf registration failed: %d\n", ret);
-		goto out;
-	}
-
-	if (cqm_enabled)
-		pr_info("Intel CQM monitoring enabled\n");
-	if (mbm_enabled)
-		pr_info("Intel MBM enabled\n");
-
-	/*
-	 * Setup the hot cpu notifier once we are sure cqm
-	 * is enabled to avoid notifier leak.
-	 */
-	cpuhp_setup_state_cpuslocked(CPUHP_AP_PERF_X86_CQM_STARTING,
-				     "perf/x86/cqm:starting",
-				     intel_cqm_cpu_starting, NULL);
-	cpuhp_setup_state_cpuslocked(CPUHP_AP_PERF_X86_CQM_ONLINE,
-				     "perf/x86/cqm:online",
-				     NULL, intel_cqm_cpu_exit);
-out:
-	cpus_read_unlock();
-
-	if (ret) {
-		kfree(str);
-		cqm_cleanup();
-		mbm_cleanup();
-	}
-
-	return ret;
-}
-device_initcall(intel_cqm_init);

arch/x86/include/asm/intel_rdt.h

···
-#ifndef _ASM_X86_INTEL_RDT_H
-#define _ASM_X86_INTEL_RDT_H
-
-#ifdef CONFIG_INTEL_RDT_A
-
-#include <linux/sched.h>
-#include <linux/kernfs.h>
-#include <linux/jump_label.h>
-
-#include <asm/intel_rdt_common.h>
-
-#define IA32_L3_QOS_CFG		0xc81
-#define IA32_L3_CBM_BASE	0xc90
-#define IA32_L2_CBM_BASE	0xd10
-#define IA32_MBA_THRTL_BASE	0xd50
-
-#define L3_QOS_CDP_ENABLE	0x01ULL
-
-/**
- * struct rdtgroup - store rdtgroup's data in resctrl file system.
- * @kn:				kernfs node
- * @rdtgroup_list:		linked list for all rdtgroups
- * @closid:			closid for this rdtgroup
- * @cpu_mask:			CPUs assigned to this rdtgroup
- * @flags:			status bits
- * @waitcount:			how many cpus expect to find this
- *				group when they acquire rdtgroup_mutex
- */
-struct rdtgroup {
-	struct kernfs_node	*kn;
-	struct list_head	rdtgroup_list;
-	int			closid;
-	struct cpumask		cpu_mask;
-	int			flags;
-	atomic_t		waitcount;
-};
-
-/* rdtgroup.flags */
-#define	RDT_DELETED		1
-
-/* rftype.flags */
-#define RFTYPE_FLAGS_CPUS_LIST	1
-
-/* List of all resource groups */
-extern struct list_head rdt_all_groups;
-
-extern int max_name_width, max_data_width;
-
-int __init rdtgroup_init(void);
-
-/**
- * struct rftype - describe each file in the resctrl file system
- * @name:	File name
- * @mode:	Access mode
- * @kf_ops:	File operations
- * @flags:	File specific RFTYPE_FLAGS_* flags
- * @seq_show:	Show content of the file
- * @write:	Write to the file
- */
-struct rftype {
-	char			*name;
-	umode_t			mode;
-	struct kernfs_ops	*kf_ops;
-	unsigned long		flags;
-
-	int (*seq_show)(struct kernfs_open_file *of,
-			struct seq_file *sf, void *v);
-	/*
-	 * write() is the generic write callback which maps directly to
-	 * kernfs write operation and overrides all other operations.
-	 * Maximum write size is determined by ->max_write_len.
-	 */
-	ssize_t (*write)(struct kernfs_open_file *of,
-			 char *buf, size_t nbytes, loff_t off);
-};
-
-/**
- * struct rdt_domain - group of cpus sharing an RDT resource
- * @list:	all instances of this resource
- * @id:		unique id for this instance
- * @cpu_mask:	which cpus share this resource
- * @ctrl_val:	array of cache or mem ctrl values (indexed by CLOSID)
- * @new_ctrl:	new ctrl value to be loaded
- * @have_new_ctrl: did user provide new_ctrl for this domain
- */
-struct rdt_domain {
-	struct list_head	list;
-	int			id;
-	struct cpumask		cpu_mask;
-	u32			*ctrl_val;
-	u32			new_ctrl;
-	bool			have_new_ctrl;
-};
-
-/**
- * struct msr_param - set a range of MSRs from a domain
- * @res:       The resource to use
- * @low:       Beginning index from base MSR
- * @high:      End index
- */
-struct msr_param {
-	struct rdt_resource	*res;
-	int			low;
-	int			high;
-};
-
-/**
- * struct rdt_cache - Cache allocation related data
- * @cbm_len:		Length of the cache bit mask
- * @min_cbm_bits:	Minimum number of consecutive bits to be set
- * @cbm_idx_mult:	Multiplier of CBM index
- * @cbm_idx_offset:	Offset of CBM index. CBM index is computed by:
- *			closid * cbm_idx_multi + cbm_idx_offset
- *			in a cache bit mask
- */
-struct rdt_cache {
-	unsigned int	cbm_len;
-	unsigned int	min_cbm_bits;
-	unsigned int	cbm_idx_mult;
-	unsigned int	cbm_idx_offset;
-};
-
-/**
- * struct rdt_membw - Memory bandwidth allocation related data
- * @max_delay:		Max throttle delay. Delay is the hardware
- *			representation for memory bandwidth.
- * @min_bw:		Minimum memory bandwidth percentage user can request
- * @bw_gran:		Granularity at which the memory bandwidth is allocated
- * @delay_linear:	True if memory B/W delay is in linear scale
- * @mb_map:		Mapping of memory B/W percentage to memory B/W delay
- */
-struct rdt_membw {
-	u32		max_delay;
-	u32		min_bw;
-	u32		bw_gran;
-	u32		delay_linear;
-	u32		*mb_map;
-};
-
-/**
- * struct rdt_resource - attributes of an RDT resource
- * @enabled:		Is this feature enabled on this machine
- * @capable:		Is this feature available on this machine
- * @name:		Name to use in "schemata" file
- * @num_closid:		Number of CLOSIDs available
- * @cache_level:	Which cache level defines scope of this resource
- * @default_ctrl:	Specifies default cache cbm or memory B/W percent.
- * @msr_base:		Base MSR address for CBMs
- * @msr_update:		Function pointer to update QOS MSRs
- * @data_width:		Character width of data when displaying
- * @domains:		All domains for this resource
- * @cache:		Cache allocation related data
- * @info_files:		resctrl info files for the resource
- * @nr_info_files:	Number of info files
- * @format_str:		Per resource format string to show domain value
- * @parse_ctrlval:	Per resource function pointer to parse control values
- */
-struct rdt_resource {
-	bool			enabled;
-	bool			capable;
-	char			*name;
-	int			num_closid;
-	int			cache_level;
-	u32			default_ctrl;
-	unsigned int		msr_base;
-	void (*msr_update)	(struct rdt_domain *d, struct msr_param *m,
-				 struct rdt_resource *r);
-	int			data_width;
-	struct list_head	domains;
-	struct rdt_cache	cache;
-	struct rdt_membw	membw;
-	struct rftype		*info_files;
-	int			nr_info_files;
-	const char		*format_str;
-	int (*parse_ctrlval)	(char *buf, struct rdt_resource *r,
-				 struct rdt_domain *d);
-};
-
-void rdt_get_cache_infofile(struct rdt_resource *r);
-void rdt_get_mba_infofile(struct rdt_resource *r);
-int parse_cbm(char *buf, struct rdt_resource *r, struct rdt_domain *d);
-int parse_bw(char *buf, struct rdt_resource *r,  struct rdt_domain *d);
-
-extern struct mutex rdtgroup_mutex;
-
-extern struct rdt_resource rdt_resources_all[];
-extern struct rdtgroup rdtgroup_default;
-DECLARE_STATIC_KEY_FALSE(rdt_enable_key);
-
-int __init rdtgroup_init(void);
-
-enum {
-	RDT_RESOURCE_L3,
-	RDT_RESOURCE_L3DATA,
-	RDT_RESOURCE_L3CODE,
-	RDT_RESOURCE_L2,
-	RDT_RESOURCE_MBA,
-
-	/* Must be the last */
-	RDT_NUM_RESOURCES,
-};
-
-#define for_each_capable_rdt_resource(r)				      \
-	for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
-	     r++)							      \
-		if (r->capable)
-
-#define for_each_enabled_rdt_resource(r)				      \
-	for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
-	     r++)							      \
-		if (r->enabled)
-
-/* CPUID.(EAX=10H, ECX=ResID=1).EAX */
-union cpuid_0x10_1_eax {
-	struct {
-		unsigned int cbm_len:5;
-	} split;
-	unsigned int full;
-};
-
-/* CPUID.(EAX=10H, ECX=ResID=3).EAX */
-union cpuid_0x10_3_eax {
-	struct {
-		unsigned int max_delay:12;
-	} split;
-	unsigned int full;
-};
-
-/* CPUID.(EAX=10H, ECX=ResID).EDX */
-union cpuid_0x10_x_edx {
-	struct {
-		unsigned int cos_max:16;
-	} split;
-	unsigned int full;
-};
-
-DECLARE_PER_CPU_READ_MOSTLY(int, cpu_closid);
-
-void rdt_ctrl_update(void *arg);
-struct rdtgroup *rdtgroup_kn_lock_live(struct kernfs_node *kn);
-void rdtgroup_kn_unlock(struct kernfs_node *kn);
-ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
-				char *buf, size_t nbytes, loff_t off);
-int rdtgroup_schemata_show(struct kernfs_open_file *of,
-			   struct seq_file *s, void *v);
-
-/*
- * intel_rdt_sched_in() - Writes the task's CLOSid to IA32_PQR_MSR
- *
- * Following considerations are made so that this has minimal impact
- * on scheduler hot path:
- * - This will stay as no-op unless we are running on an Intel SKU
- *   which supports resource control and we enable by mounting the
- *   resctrl file system.
- * - Caches the per cpu CLOSid values and does the MSR write only
- *   when a task with a different CLOSid is scheduled in.
- *
- * Must be called with preemption disabled.
- */
-static inline void intel_rdt_sched_in(void)
-{
-	if (static_branch_likely(&rdt_enable_key)) {
-		struct intel_pqr_state *state = this_cpu_ptr(&pqr_state);
-		int closid;
-
-		/*
-		 * If this task has a closid assigned, use it.
-		 * Else use the closid assigned to this cpu.
-		 */
-		closid = current->closid;
-		if (closid == 0)
-			closid = this_cpu_read(cpu_closid);
-
-		if (closid != state->closid) {
-			state->closid = closid;
-			wrmsr(MSR_IA32_PQR_ASSOC, state->rmid, closid);
-		}
-	}
-}
-
-#else
-
-static inline void intel_rdt_sched_in(void) {}
-
-#endif /* CONFIG_INTEL_RDT_A */
-#endif /* _ASM_X86_INTEL_RDT_H */

arch/x86/include/asm/intel_rdt_common.h

···
-#ifndef _ASM_X86_INTEL_RDT_COMMON_H
-#define _ASM_X86_INTEL_RDT_COMMON_H
-
-#define MSR_IA32_PQR_ASSOC	0x0c8f
-
-/**
- * struct intel_pqr_state - State cache for the PQR MSR
- * @rmid:		The cached Resource Monitoring ID
- * @closid:		The cached Class Of Service ID
- * @rmid_usecnt:	The usage counter for rmid
- *
- * The upper 32 bits of MSR_IA32_PQR_ASSOC contain closid and the
- * lower 10 bits rmid. The update to MSR_IA32_PQR_ASSOC always
- * contains both parts, so we need to cache them.
- *
- * The cache also helps to avoid pointless updates if the value does
- * not change.
- */
-struct intel_pqr_state {
-	u32			rmid;
-	u32			closid;
-	int			rmid_usecnt;
-};
-
-DECLARE_PER_CPU(struct intel_pqr_state, pqr_state);
-
-#endif /* _ASM_X86_INTEL_RDT_COMMON_H */

arch/x86/include/asm/intel_rdt_sched.h

···
+#ifndef _ASM_X86_INTEL_RDT_SCHED_H
+#define _ASM_X86_INTEL_RDT_SCHED_H
+
+#ifdef CONFIG_INTEL_RDT
+
+#include <linux/sched.h>
+#include <linux/jump_label.h>
+
+#define IA32_PQR_ASSOC	0x0c8f
+
+/**
+ * struct intel_pqr_state - State cache for the PQR MSR
+ * @cur_rmid:		The cached Resource Monitoring ID
+ * @cur_closid:	The cached Class Of Service ID
+ * @default_rmid:	The user assigned Resource Monitoring ID
+ * @default_closid:	The user assigned cached Class Of Service ID
+ *
+ * The upper 32 bits of IA32_PQR_ASSOC contain closid and the
+ * lower 10 bits rmid. The update to IA32_PQR_ASSOC always
+ * contains both parts, so we need to cache them. This also
+ * stores the user configured per cpu CLOSID and RMID.
+ *
+ * The cache also helps to avoid pointless updates if the value does
+ * not change.
+ */
+struct intel_pqr_state {
+	u32			cur_rmid;
+	u32			cur_closid;
+	u32			default_rmid;
+	u32			default_closid;
+};
+
+DECLARE_PER_CPU(struct intel_pqr_state, pqr_state);
+
+DECLARE_STATIC_KEY_FALSE(rdt_enable_key);
+DECLARE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
+DECLARE_STATIC_KEY_FALSE(rdt_mon_enable_key);
+
+/*
+ * __intel_rdt_sched_in() - Writes the task's CLOSid/RMID to IA32_PQR_MSR
+ *
+ * Following considerations are made so that this has minimal impact
+ * on scheduler hot path:
+ * - This will stay as no-op unless we are running on an Intel SKU
+ *   which supports resource control or monitoring and we enable by
+ *   mounting the resctrl file system.
+ * - Caches the per cpu CLOSid/RMID values and does the MSR write only
+ *   when a task with a different CLOSid/RMID is scheduled in.
+ * - We allocate RMIDs/CLOSids globally in order to keep this as
+ *   simple as possible.
+ * Must be called with preemption disabled.
+ */
+static void __intel_rdt_sched_in(void)
+{
+	struct intel_pqr_state *state = this_cpu_ptr(&pqr_state);
+	u32 closid = state->default_closid;
+	u32 rmid = state->default_rmid;
+
+	/*
+	 * If this task has a closid/rmid assigned, use it.
+	 * Else use the closid/rmid assigned to this cpu.
+	 */
+	if (static_branch_likely(&rdt_alloc_enable_key)) {
+		if (current->closid)
+			closid = current->closid;
+	}
+
+	if (static_branch_likely(&rdt_mon_enable_key)) {
+		if (current->rmid)
+			rmid = current->rmid;
+	}
+
+	if (closid != state->cur_closid || rmid != state->cur_rmid) {
+		state->cur_closid = closid;
+		state->cur_rmid = rmid;
+		wrmsr(IA32_PQR_ASSOC, rmid, closid);
+	}
+}
+
+static inline void intel_rdt_sched_in(void)
+{
+	if (static_branch_likely(&rdt_enable_key))
+		__intel_rdt_sched_in();
+}
+
+#else
+
+static inline void intel_rdt_sched_in(void) {}
+
+#endif /* CONFIG_INTEL_RDT */
+
+#endif /* _ASM_X86_INTEL_RDT_SCHED_H */

arch/x86/kernel/cpu/Makefile

···
 obj-$(CONFIG_CPU_SUP_TRANSMETA_32)	+= transmeta.o
 obj-$(CONFIG_CPU_SUP_UMC_32)		+= umc.o
 
-obj-$(CONFIG_INTEL_RDT_A)	+= intel_rdt.o intel_rdt_rdtgroup.o intel_rdt_schemata.o
+obj-$(CONFIG_INTEL_RDT)	+= intel_rdt.o intel_rdt_rdtgroup.o intel_rdt_monitor.o intel_rdt_ctrlmondata.o
 
 obj-$(CONFIG_X86_MCE)			+= mcheck/
 obj-$(CONFIG_MTRR)			+= mtrr/

arch/x86/kernel/cpu/intel_rdt.c

···
 #include <linux/cpuhotplug.h>
 
 #include <asm/intel-family.h>
-#include <asm/intel_rdt.h>
+#include <asm/intel_rdt_sched.h>
+#include "intel_rdt.h"
 
 #define MAX_MBA_BW	100u
 #define MBA_IS_LINEAR	0x4
···
 /* Mutex to protect rdtgroup access. */
 DEFINE_MUTEX(rdtgroup_mutex);
 
-DEFINE_PER_CPU_READ_MOSTLY(int, cpu_closid);
+/*
+ * The cached intel_pqr_state is strictly per CPU and can never be
+ * updated from a remote CPU. Functions which modify the state
+ * are called with interrupts disabled and no preemption, which
+ * is sufficient for the protection.
+ */
+DEFINE_PER_CPU(struct intel_pqr_state, pqr_state);
 
 /*
  * Used to store the max resource name width and max resource data width
  * to display the schemata in a tabular format
  */
 int max_name_width, max_data_width;
+
+/*
+ * Global boolean for rdt_alloc which is true if any
+ * resource allocation is enabled.
+ */
+bool rdt_alloc_capable;
 
 static void
 mba_wrmsr(struct rdt_domain *d, struct msr_param *m, struct rdt_resource *r);
···
 #define domain_init(id) LIST_HEAD_INIT(rdt_resources_all[id].domains)
 
 struct rdt_resource rdt_resources_all[] = {
+	[RDT_RESOURCE_L3] =
 	{
+		.rid			= RDT_RESOURCE_L3,
 		.name			= "L3",
 		.domains		= domain_init(RDT_RESOURCE_L3),
 		.msr_base		= IA32_L3_CBM_BASE,
···
 		},
 		.parse_ctrlval		= parse_cbm,
 		.format_str		= "%d=%0*x",
+		.fflags			= RFTYPE_RES_CACHE,
 	},
+	[RDT_RESOURCE_L3DATA] =
 	{
+		.rid			= RDT_RESOURCE_L3DATA,
 		.name			= "L3DATA",
 		.domains		= domain_init(RDT_RESOURCE_L3DATA),
 		.msr_base		= IA32_L3_CBM_BASE,
···
 		},
 		.parse_ctrlval		= parse_cbm,
 		.format_str		= "%d=%0*x",
+		.fflags			= RFTYPE_RES_CACHE,
 	},
+	[RDT_RESOURCE_L3CODE] =
 	{
+		.rid			= RDT_RESOURCE_L3CODE,
 		.name			= "L3CODE",
 		.domains		= domain_init(RDT_RESOURCE_L3CODE),
 		.msr_base		= IA32_L3_CBM_BASE,
···
 		},
 		.parse_ctrlval		= parse_cbm,
 		.format_str		= "%d=%0*x",
+		.fflags			= RFTYPE_RES_CACHE,
 	},
+	[RDT_RESOURCE_L2] =
 	{
+		.rid			= RDT_RESOURCE_L2,
 		.name			= "L2",
 		.domains		= domain_init(RDT_RESOURCE_L2),
 		.msr_base		= IA32_L2_CBM_BASE,
···
 		},
 		.parse_ctrlval		= parse_cbm,
 		.format_str		= "%d=%0*x",
+		.fflags			= RFTYPE_RES_CACHE,
 	},
+	[RDT_RESOURCE_MBA] =
 	{
+		.rid			= RDT_RESOURCE_MBA,
 		.name			= "MB",
 		.domains		= domain_init(RDT_RESOURCE_MBA),
 		.msr_base		= IA32_MBA_THRTL_BASE,
···
 		.cache_level		= 3,
 		.parse_ctrlval		= parse_bw,
 		.format_str		= "%d=%*d",
+		.fflags			= RFTYPE_RES_MB,
 	},
 };
 
···
  * is always 20 on hsw server parts. The minimum cache bitmask length
  * allowed for HSW server is always 2 bits. Hardcode all of them.
  */
-static inline bool cache_alloc_hsw_probe(void)
+static inline void cache_alloc_hsw_probe(void)
 {
-	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
-	    boot_cpu_data.x86 == 6 &&
-	    boot_cpu_data.x86_model == INTEL_FAM6_HASWELL_X) {
-		struct rdt_resource *r  = &rdt_resources_all[RDT_RESOURCE_L3];
-		u32 l, h, max_cbm = BIT_MASK(20) - 1;
+	struct rdt_resource *r  = &rdt_resources_all[RDT_RESOURCE_L3];
+	u32 l, h, max_cbm = BIT_MASK(20) - 1;
 
-		if (wrmsr_safe(IA32_L3_CBM_BASE, max_cbm, 0))
-			return false;
-		rdmsr(IA32_L3_CBM_BASE, l, h);
+	if (wrmsr_safe(IA32_L3_CBM_BASE, max_cbm, 0))
+		return;
+	rdmsr(IA32_L3_CBM_BASE, l, h);
 
-		/* If all the bits were set in MSR, return success */
-		if (l != max_cbm)
-			return false;
+	/* If all the bits were set in MSR, return success */
+	if (l != max_cbm)
+		return;
 
-		r->num_closid = 4;
-		r->default_ctrl = max_cbm;
-		r->cache.cbm_len = 20;
-		r->cache.min_cbm_bits = 2;
-		r->capable = true;
-		r->enabled = true;
+	r->num_closid = 4;
+	r->default_ctrl = max_cbm;
+	r->cache.cbm_len = 20;
+	r->cache.shareable_bits = 0xc0000;
+	r->cache.min_cbm_bits = 2;
+	r->alloc_capable = true;
+	r->alloc_enabled = true;
 
-		return true;
-	}
-
-	return false;
+	rdt_alloc_capable = true;
 }
 
 /*
···
 			return false;
 	}
 	r->data_width = 3;
-	rdt_get_mba_infofile(r);
 
-	r->capable = true;
-	r->enabled = true;
+	r->alloc_capable = true;
+	r->alloc_enabled = true;
 
 	return true;
 }
 
-static void rdt_get_cache_config(int idx, struct rdt_resource *r)
+static void rdt_get_cache_alloc_cfg(int idx, struct rdt_resource *r)
 {
 	union cpuid_0x10_1_eax eax;
 	union cpuid_0x10_x_edx edx;
···
 	r->num_closid = edx.split.cos_max + 1;
 	r->cache.cbm_len = eax.split.cbm_len + 1;
 	r->default_ctrl = BIT_MASK(eax.split.cbm_len + 1) - 1;
+	r->cache.shareable_bits = ebx & r->default_ctrl;
 	r->data_width = (r->cache.cbm_len + 3) / 4;
-	rdt_get_cache_infofile(r);
-	r->capable = true;
-	r->enabled = true;
+	r->alloc_capable = true;
+	r->alloc_enabled = true;
 }
 
 static void rdt_get_cdp_l3_config(int type)
···
 	r->cache.cbm_len = r_l3->cache.cbm_len;
 	r->default_ctrl = r_l3->default_ctrl;
 	r->data_width = (r->cache.cbm_len + 3) / 4;
-	r->capable = true;
+	r->alloc_capable = true;
 	/*
 	 * By default, CDP is disabled. CDP can be enabled by mount parameter
 	 * "cdp" during resctrl file system mount time.
 	 */
-	r->enabled = false;
+	r->alloc_enabled = false;
 }
 
 static int get_cache_id(int cpu, int level)
···
 		wrmsrl(r->msr_base + cbm_idx(r, i), d->ctrl_val[i]);
 }
 
+struct rdt_domain *get_domain_from_cpu(int cpu, struct rdt_resource *r)
+{
+	struct rdt_domain *d;
+
+	list_for_each_entry(d, &r->domains, list) {
+		/* Find the domain that contains this CPU */
+		if (cpumask_test_cpu(cpu, &d->cpu_mask))
+			return d;
+	}
+
+	return NULL;
+}
+
 void rdt_ctrl_update(void *arg)
 {
 	struct msr_param *m = arg;
···
 	int cpu = smp_processor_id();
 	struct rdt_domain *d;
 
-	list_for_each_entry(d, &r->domains, list) {
-		/* Find the domain that contains this CPU */
-		if (cpumask_test_cpu(cpu, &d->cpu_mask)) {
-			r->msr_update(d, m, r);
-			return;
-		}
+	d = get_domain_from_cpu(cpu, r);
+	if (d) {
+		r->msr_update(d, m, r);
+		return;
 	}
 	pr_warn_once("cpu %d not found in any domain for resource %s\n",
 		     cpu, r->name);
···
  * caller, return the first domain whose id is bigger than the input id.
  * The domain list is sorted by id in ascending order.
  */
-static struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id,
-					  struct list_head **pos)
+struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id,
+				   struct list_head **pos)
 {
 	struct rdt_domain *d;
 	struct list_head *l;
···
 	return 0;
 }
 
+static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_domain *d)
+{
+	size_t tsize;
+
+	if (is_llc_occupancy_enabled()) {
+		d->rmid_busy_llc = kcalloc(BITS_TO_LONGS(r->num_rmid),
+					   sizeof(unsigned long),
+					   GFP_KERNEL);
+		if (!d->rmid_busy_llc)
+			return -ENOMEM;
+		INIT_DELAYED_WORK(&d->cqm_limbo, cqm_handle_limbo);
+	}
+	if (is_mbm_total_enabled()) {
+		tsize = sizeof(*d->mbm_total);
+		d->mbm_total = kcalloc(r->num_rmid, tsize, GFP_KERNEL);
+		if (!d->mbm_total) {
+			kfree(d->rmid_busy_llc);
+			return -ENOMEM;
+		}
+	}
+	if (is_mbm_local_enabled()) {
+		tsize = sizeof(*d->mbm_local);
+		d->mbm_local = kcalloc(r->num_rmid, tsize, GFP_KERNEL);
+		if (!d->mbm_local) {
+			kfree(d->rmid_busy_llc);
+			kfree(d->mbm_total);
+			return -ENOMEM;
+		}
+	}
+
+	if (is_mbm_enabled()) {
+		INIT_DELAYED_WORK(&d->mbm_over, mbm_handle_overflow);
+		mbm_setup_overflow_handler(d, MBM_OVERFLOW_INTERVAL);
+	}
+
+	return 0;
+}
+
 /*
  * domain_add_cpu - Add a cpu to a resource's domain list.
  *
···
 		return;
 
 	d->id = id;
+	cpumask_set_cpu(cpu, &d->cpu_mask);
 
-	if (domain_setup_ctrlval(r, d)) {
+	if (r->alloc_capable && domain_setup_ctrlval(r, d)) {
 		kfree(d);
 		return;
 	}
 
-	cpumask_set_cpu(cpu, &d->cpu_mask);
+	if (r->mon_capable && domain_setup_mon_state(r, d)) {
+		kfree(d);
+		return;
+	}
+
 	list_add_tail(&d->list, add_pos);
+
+	/*
+	 * If resctrl is mounted, add
+	 * per domain monitor data directories.
+	 */
+	if (static_branch_unlikely(&rdt_mon_enable_key))
+		mkdir_mondata_subdir_allrdtgrp(r, d);
 }
 
 static void domain_remove_cpu(int cpu, struct rdt_resource *r)
···
 
 	cpumask_clear_cpu(cpu, &d->cpu_mask);
 	if (cpumask_empty(&d->cpu_mask)) {
+		/*
+		 * If resctrl is mounted, remove all the
+		 * per domain monitor data directories.
+		 */
+		if (static_branch_unlikely(&rdt_mon_enable_key))
+			rmdir_mondata_subdir_allrdtgrp(r, d->id);
 		kfree(d->ctrl_val);
+		kfree(d->rmid_busy_llc);
+		kfree(d->mbm_total);
+		kfree(d->mbm_local);
 		list_del(&d->list);
+		if (is_mbm_enabled())
+			cancel_delayed_work(&d->mbm_over);
+		if (is_llc_occupancy_enabled() &&  has_busy_rmid(r, d)) {
+			/*
+			 * When a package is going down, forcefully
+			 * decrement rmid->ebusy. There is no way to know
+			 * that the L3 was flushed and hence may lead to
+			 * incorrect counts in rare scenarios, but leaving
+			 * the RMID as busy creates RMID leaks if the
+			 * package never comes back.
+			 */
+			__check_limbo(d, true);
+			cancel_delayed_work(&d->cqm_limbo);
+		}
+
 		kfree(d);
+		return;
+	}
+
+	if (r == &rdt_resources_all[RDT_RESOURCE_L3]) {
+		if (is_mbm_enabled() && cpu == d->mbm_work_cpu) {
+			cancel_delayed_work(&d->mbm_over);
+			mbm_setup_overflow_handler(d, 0);
+		}
+		if (is_llc_occupancy_enabled() && cpu == d->cqm_work_cpu &&
+		    has_busy_rmid(r, d)) {
+			cancel_delayed_work(&d->cqm_limbo);
+			cqm_setup_limbo_handler(d, 0);
+		}
 	}
 }
 
-static void clear_closid(int cpu)
+static void clear_closid_rmid(int cpu)
 {
 	struct intel_pqr_state *state = this_cpu_ptr(&pqr_state);
 
-	per_cpu(cpu_closid, cpu) = 0;
-	state->closid = 0;
-	wrmsr(MSR_IA32_PQR_ASSOC, state->rmid, 0);
+	state->default_closid = 0;
+	state->default_rmid = 0;
+	state->cur_closid = 0;
+	state->cur_rmid = 0;
+	wrmsr(IA32_PQR_ASSOC, 0, 0);
 }
 
 static int intel_rdt_online_cpu(unsigned int cpu)
···
 		domain_add_cpu(cpu, r);
 	/* The cpu is set in default rdtgroup after online. */
 	cpumask_set_cpu(cpu, &rdtgroup_default.cpu_mask);
-	clear_closid(cpu);
+	clear_closid_rmid(cpu);
 	mutex_unlock(&rdtgroup_mutex);
 
 	return 0;
+}
+
+static void clear_childcpus(struct rdtgroup *r, unsigned int cpu)
+{
+	struct rdtgroup *cr;
+
+	list_for_each_entry(cr, &r->mon.crdtgrp_list, mon.crdtgrp_list) {
+		if (cpumask_test_and_clear_cpu(cpu, &cr->cpu_mask)) {
+			break;
+		}
+	}
 }
 
 static int intel_rdt_offline_cpu(unsigned int cpu)
···
 	for_each_capable_rdt_resource(r)
 		domain_remove_cpu(cpu, r);
 	list_for_each_entry(rdtgrp, &rdt_all_groups, rdtgroup_list) {
-		if (cpumask_test_and_clear_cpu(cpu, &rdtgrp->cpu_mask))
+		if (cpumask_test_and_clear_cpu(cpu, &rdtgrp->cpu_mask)) {
+			clear_childcpus(rdtgrp, cpu);
 			break;
+		}
 	}
-	clear_closid(cpu);
+	clear_closid_rmid(cpu);
 	mutex_unlock(&rdtgroup_mutex);
 
 	return 0;
···
 	struct rdt_resource *r;
 	int cl;
 
-	for_each_capable_rdt_resource(r) {
+	for_each_alloc_capable_rdt_resource(r) {
 		cl = strlen(r->name);
 		if (cl > max_name_width)
 			max_name_width = cl;
···
 	}
 }
 
-static __init bool get_rdt_resources(void)
+enum {
+	RDT_FLAG_CMT,
+	RDT_FLAG_MBM_TOTAL,
+	RDT_FLAG_MBM_LOCAL,
+	RDT_FLAG_L3_CAT,
+	RDT_FLAG_L3_CDP,
+	RDT_FLAG_L2_CAT,
+	RDT_FLAG_MBA,
+};
+
+#define RDT_OPT(idx, n, f)	\
+[idx] = {			\
+	.name = n,		\
+	.flag = f		\
+}
+
+struct rdt_options {
+	char	*name;
+	int	flag;
+	bool	force_off, force_on;
+};
+
+static struct rdt_options rdt_options[]  __initdata = {
+	RDT_OPT(RDT_FLAG_CMT,	    "cmt",	X86_FEATURE_CQM_OCCUP_LLC),
+	RDT_OPT(RDT_FLAG_MBM_TOTAL, "mbmtotal", X86_FEATURE_CQM_MBM_TOTAL),
+	RDT_OPT(RDT_FLAG_MBM_LOCAL, "mbmlocal", X86_FEATURE_CQM_MBM_LOCAL),
+	RDT_OPT(RDT_FLAG_L3_CAT,    "l3cat",	X86_FEATURE_CAT_L3),
+	RDT_OPT(RDT_FLAG_L3_CDP,    "l3cdp",	X86_FEATURE_CDP_L3),
+	RDT_OPT(RDT_FLAG_L2_CAT,    "l2cat",	X86_FEATURE_CAT_L2),
+	RDT_OPT(RDT_FLAG_MBA,	    "mba",	X86_FEATURE_MBA),
+};
+#define NUM_RDT_OPTIONS ARRAY_SIZE(rdt_options)
+
+static int __init set_rdt_options(char *str)
+{
+	struct rdt_options *o;
+	bool force_off;
+	char *tok;
+
+	if (*str == '=')
+		str++;
+	while ((tok = strsep(&str, ",")) != NULL) {
+		force_off = *tok == '!';
+		if (force_off)
+			tok++;
+		for (o = rdt_options; o < &rdt_options[NUM_RDT_OPTIONS]; o++) {
+			if (strcmp(tok, o->name) == 0) {
+				if (force_off)
+					o->force_off = true;
+				else
+					o->force_on = true;
+				break;
+			}
+		}
+	}
+	return 1;
+}
+__setup("rdt", set_rdt_options);
+
+static bool __init rdt_cpu_has(int flag)
+{
+	bool ret = boot_cpu_has(flag);
+	struct rdt_options *o;
+
+	if (!ret)
+		return ret;
+
+	for (o = rdt_options; o < &rdt_options[NUM_RDT_OPTIONS]; o++) {
+		if (flag == o->flag) {
+			if (o->force_off)
+				ret = false;
+			if (o->force_on)
+				ret = true;
+			break;
+		}
+	}
+	return ret;
+}
+
+static __init bool get_rdt_alloc_resources(void)
 {
 	bool ret = false;
 
-	if (cache_alloc_hsw_probe())
+	if (rdt_alloc_capable)
 		return true;
 
 	if (!boot_cpu_has(X86_FEATURE_RDT_A))
 		return false;
 
-	if (boot_cpu_has(X86_FEATURE_CAT_L3)) {
-		rdt_get_cache_config(1, &rdt_resources_all[RDT_RESOURCE_L3]);
-		if (boot_cpu_has(X86_FEATURE_CDP_L3)) {
+	if (rdt_cpu_has(X86_FEATURE_CAT_L3)) {
+		rdt_get_cache_alloc_cfg(1, &rdt_resources_all[RDT_RESOURCE_L3]);
+		if (rdt_cpu_has(X86_FEATURE_CDP_L3)) {
 			rdt_get_cdp_l3_config(RDT_RESOURCE_L3DATA);
 			rdt_get_cdp_l3_config(RDT_RESOURCE_L3CODE);
 		}
 		ret = true;
 	}
-	if (boot_cpu_has(X86_FEATURE_CAT_L2)) {
+	if (rdt_cpu_has(X86_FEATURE_CAT_L2)) {
 		/* CPUID 0x10.2 fields are same format at 0x10.1 */
-		rdt_get_cache_config(2, &rdt_resources_all[RDT_RESOURCE_L2]);
+		rdt_get_cache_alloc_cfg(2, &rdt_resources_all[RDT_RESOURCE_L2]);
 		ret = true;
 	}
 
-	if (boot_cpu_has(X86_FEATURE_MBA)) {
+	if (rdt_cpu_has(X86_FEATURE_MBA)) {
 		if (rdt_get_mem_config(&rdt_resources_all[RDT_RESOURCE_MBA]))
 			ret = true;
 	}
-
 	return ret;
+}
+
+static __init bool get_rdt_mon_resources(void)
+{
+	if (rdt_cpu_has(X86_FEATURE_CQM_OCCUP_LLC))
+		rdt_mon_features |= (1 << QOS_L3_OCCUP_EVENT_ID);
+	if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL))
+		rdt_mon_features |= (1 << QOS_L3_MBM_TOTAL_EVENT_ID);
+	if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL))
+		rdt_mon_features |= (1 << QOS_L3_MBM_LOCAL_EVENT_ID);
+
+	if (!rdt_mon_features)
+		return false;
+
+	return !rdt_get_mon_l3_config(&rdt_resources_all[RDT_RESOURCE_L3]);
+}
+
+static __init void rdt_quirks(void)
+{
+	switch (boot_cpu_data.x86_model) {
+	case INTEL_FAM6_HASWELL_X:
+		if (!rdt_options[RDT_FLAG_L3_CAT].force_off)
+			cache_alloc_hsw_probe();
+		break;
+	case INTEL_FAM6_SKYLAKE_X:
+		if (boot_cpu_data.x86_mask <= 4)
+			set_rdt_options("!cmt,!mbmtotal,!mbmlocal,!l3cat");
+	}
+}
+
+static __init bool get_rdt_resources(void)
+{
+	rdt_quirks();
+	rdt_alloc_capable = get_rdt_alloc_resources();
+	rdt_mon_capable = get_rdt_mon_resources();
+
+	return (rdt_mon_capable || rdt_alloc_capable);
 }
 
 static int __init intel_rdt_late_init(void)
···
 		return ret;
 	}
 
-	for_each_capable_rdt_resource(r)
+	for_each_alloc_capable_rdt_resource(r)
 		pr_info("Intel RDT %s allocation detected\n", r->name);
+
+	for_each_mon_capable_rdt_resource(r)
+		pr_info("Intel RDT %s monitoring detected\n", r->name);
 
 	return 0;
 }

arch/x86/kernel/cpu/intel_rdt.h

···
+#ifndef _ASM_X86_INTEL_RDT_H
+#define _ASM_X86_INTEL_RDT_H
+
+#include <linux/sched.h>
+#include <linux/kernfs.h>
+#include <linux/jump_label.h>
+
+#define IA32_L3_QOS_CFG		0xc81
+#define IA32_L3_CBM_BASE	0xc90
+#define IA32_L2_CBM_BASE	0xd10
+#define IA32_MBA_THRTL_BASE	0xd50
+
+#define L3_QOS_CDP_ENABLE	0x01ULL
+
+/*
+ * Event IDs are used to program IA32_QM_EVTSEL before reading event
+ * counter from IA32_QM_CTR
+ */
+#define QOS_L3_OCCUP_EVENT_ID		0x01
+#define QOS_L3_MBM_TOTAL_EVENT_ID	0x02
+#define QOS_L3_MBM_LOCAL_EVENT_ID	0x03
+
+#define CQM_LIMBOCHECK_INTERVAL	1000
+
+#define MBM_CNTR_WIDTH			24
+#define MBM_OVERFLOW_INTERVAL		1000
+
+#define RMID_VAL_ERROR			BIT_ULL(63)
+#define RMID_VAL_UNAVAIL		BIT_ULL(62)
+
+DECLARE_STATIC_KEY_FALSE(rdt_enable_key);
+
+/**
+ * struct mon_evt - Entry in the event list of a resource
+ * @evtid:		event id
+ * @name:		name of the event
+ */
+struct mon_evt {
+	u32			evtid;
+	char			*name;
+	struct list_head	list;
+};
+
+/**
+ * struct mon_data_bits - Monitoring details for each event file
+ * @rid:               Resource id associated with the event file.
+ * @evtid:             Event id associated with the event file
+ * @domid:             The domain to which the event file belongs
+ */
+union mon_data_bits {
+	void *priv;
+	struct {
+		unsigned int rid	: 10;
+		unsigned int evtid	: 8;
+		unsigned int domid	: 14;
+	} u;
+};
+
+struct rmid_read {
+	struct rdtgroup		*rgrp;
+	struct rdt_domain	*d;
+	int			evtid;
+	bool			first;
+	u64			val;
+};
+
+extern unsigned int intel_cqm_threshold;
+extern bool rdt_alloc_capable;
+extern bool rdt_mon_capable;
+extern unsigned int rdt_mon_features;
+
+enum rdt_group_type {
+	RDTCTRL_GROUP = 0,
+	RDTMON_GROUP,
+	RDT_NUM_GROUP,
+};
+
+/**
+ * struct mongroup - store mon group's data in resctrl fs.
+ * @mon_data_kn		kernlfs node for the mon_data directory
+ * @parent:			parent rdtgrp
+ * @crdtgrp_list:		child rdtgroup node list
+ * @rmid:			rmid for this rdtgroup
+ */
+struct mongroup {
+	struct kernfs_node	*mon_data_kn;
+	struct rdtgroup		*parent;
+	struct list_head	crdtgrp_list;
+	u32			rmid;
+};
+
+/**
+ * struct rdtgroup - store rdtgroup's data in resctrl file system.
+ * @kn:				kernfs node
+ * @rdtgroup_list:		linked list for all rdtgroups
+ * @closid:			closid for this rdtgroup
+ * @cpu_mask:			CPUs assigned to this rdtgroup
+ * @flags:			status bits
+ * @waitcount:			how many cpus expect to find this
+ *				group when they acquire rdtgroup_mutex
+ * @type:			indicates type of this rdtgroup - either
+ *				monitor only or ctrl_mon group
+ * @mon:			mongroup related data
+ */
+struct rdtgroup {
+	struct kernfs_node	*kn;
+	struct list_head	rdtgroup_list;
+	u32			closid;
+	struct cpumask		cpu_mask;
+	int			flags;
+	atomic_t		waitcount;
+	enum rdt_group_type	type;
+	struct mongroup		mon;
+};
+
+/* rdtgroup.flags */
+#define	RDT_DELETED		1
+
+/* rftype.flags */
+#define RFTYPE_FLAGS_CPUS_LIST	1
+
+/*
+ * Define the file type flags for base and info directories.
+ */
+#define RFTYPE_INFO			BIT(0)
+#define RFTYPE_BASE			BIT(1)
+#define RF_CTRLSHIFT			4
+#define RF_MONSHIFT			5
+#define RFTYPE_CTRL			BIT(RF_CTRLSHIFT)
+#define RFTYPE_MON			BIT(RF_MONSHIFT)
+#define RFTYPE_RES_CACHE		BIT(8)
+#define RFTYPE_RES_MB			BIT(9)
+#define RF_CTRL_INFO			(RFTYPE_INFO | RFTYPE_CTRL)
+#define RF_MON_INFO			(RFTYPE_INFO | RFTYPE_MON)
+#define RF_CTRL_BASE			(RFTYPE_BASE | RFTYPE_CTRL)
+
+/* List of all resource groups */
+extern struct list_head rdt_all_groups;
+
+extern int max_name_width, max_data_width;
+
+int __init rdtgroup_init(void);
+
+/**
+ * struct rftype - describe each file in the resctrl file system
+ * @name:	File name
+ * @mode:	Access mode
+ * @kf_ops:	File operations
+ * @flags:	File specific RFTYPE_FLAGS_* flags
+ * @fflags:	File specific RF_* or RFTYPE_* flags
+ * @seq_show:	Show content of the file
+ * @write:	Write to the file
+ */
+struct rftype {
+	char			*name;
+	umode_t			mode;
+	struct kernfs_ops	*kf_ops;
+	unsigned long		flags;
+	unsigned long		fflags;
+
+	int (*seq_show)(struct kernfs_open_file *of,
+			struct seq_file *sf, void *v);
+	/*
+	 * write() is the generic write callback which maps directly to
+	 * kernfs write operation and overrides all other operations.
+	 * Maximum write size is determined by ->max_write_len.
+	 */
+	ssize_t (*write)(struct kernfs_open_file *of,
+			 char *buf, size_t nbytes, loff_t off);
+};
+
+/**
+ * struct mbm_state - status for each MBM counter in each domain
+ * @chunks:	Total data moved (multiply by rdt_group.mon_scale to get bytes)
+ * @prev_msr	Value of IA32_QM_CTR for this RMID last time we read it
+ */
+struct mbm_state {
+	u64	chunks;
+	u64	prev_msr;
+};
+
+/**
+ * struct rdt_domain - group of cpus sharing an RDT resource
+ * @list:	all instances of this resource
+ * @id:		unique id for this instance
+ * @cpu_mask:	which cpus share this resource
+ * @rmid_busy_llc:
+ *		bitmap of which limbo RMIDs are above threshold
+ * @mbm_total:	saved state for MBM total bandwidth
+ * @mbm_local:	saved state for MBM local bandwidth
+ * @mbm_over:	worker to periodically read MBM h/w counters
+ * @cqm_limbo:	worker to periodically read CQM h/w counters
+ * @mbm_work_cpu:
+ *		worker cpu for MBM h/w counters
+ * @cqm_work_cpu:
+ *		worker cpu for CQM h/w counters
+ * @ctrl_val:	array of cache or mem ctrl values (indexed by CLOSID)
+ * @new_ctrl:	new ctrl value to be loaded
+ * @have_new_ctrl: did user provide new_ctrl for this domain
+ */
+struct rdt_domain {
+	struct list_head	list;
+	int			id;
+	struct cpumask		cpu_mask;
+	unsigned long		*rmid_busy_llc;
+	struct mbm_state	*mbm_total;
+	struct mbm_state	*mbm_local;
+	struct delayed_work	mbm_over;
+	struct delayed_work	cqm_limbo;
+	int			mbm_work_cpu;
+	int			cqm_work_cpu;
+	u32			*ctrl_val;
+	u32			new_ctrl;
+	bool			have_new_ctrl;
+};
+
+/**
+ * struct msr_param - set a range of MSRs from a domain
+ * @res:       The resource to use
+ * @low:       Beginning index from base MSR
+ * @high:      End index
+ */
+struct msr_param {
+	struct rdt_resource	*res;
+	int			low;
+	int			high;
+};
+
+/**
+ * struct rdt_cache - Cache allocation related data
+ * @cbm_len:		Length of the cache bit mask
+ * @min_cbm_bits:	Minimum number of consecutive bits to be set
+ * @cbm_idx_mult:	Multiplier of CBM index
+ * @cbm_idx_offset:	Offset of CBM index. CBM index is computed by:
+ *			closid * cbm_idx_multi + cbm_idx_offset
+ *			in a cache bit mask
+ * @shareable_bits:	Bitmask of shareable resource with other
+ *			executing entities
+ */
+struct rdt_cache {
+	unsigned int	cbm_len;
+	unsigned int	min_cbm_bits;
+	unsigned int	cbm_idx_mult;
+	unsigned int	cbm_idx_offset;
+	unsigned int	shareable_bits;
+};
+
+/**
+ * struct rdt_membw - Memory bandwidth allocation related data
+ * @max_delay:		Max throttle delay. Delay is the hardware
+ *			representation for memory bandwidth.
+ * @min_bw:		Minimum memory bandwidth percentage user can request
+ * @bw_gran:		Granularity at which the memory bandwidth is allocated
+ * @delay_linear:	True if memory B/W delay is in linear scale
+ * @mb_map:		Mapping of memory B/W percentage to memory B/W delay
+ */
+struct rdt_membw {
+	u32		max_delay;
+	u32		min_bw;
+	u32		bw_gran;
+	u32		delay_linear;
+	u32		*mb_map;
+};
+
+static inline bool is_llc_occupancy_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_OCCUP_EVENT_ID));
+}
+
+static inline bool is_mbm_total_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_MBM_TOTAL_EVENT_ID));
+}
+
+static inline bool is_mbm_local_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_MBM_LOCAL_EVENT_ID));
+}
+
+static inline bool is_mbm_enabled(void)
+{
+	return (is_mbm_total_enabled() || is_mbm_local_enabled());
+}
+
+static inline bool is_mbm_event(int e)
+{
+	return (e >= QOS_L3_MBM_TOTAL_EVENT_ID &&
+		e <= QOS_L3_MBM_LOCAL_EVENT_ID);
+}
+
+/**
+ * struct rdt_resource - attributes of an RDT resource
+ * @rid:		The index of the resource
+ * @alloc_enabled:	Is allocation enabled on this machine
+ * @mon_enabled:		Is monitoring enabled for this feature
+ * @alloc_capable:	Is allocation available on this machine
+ * @mon_capable:		Is monitor feature available on this machine
+ * @name:		Name to use in "schemata" file
+ * @num_closid:		Number of CLOSIDs available
+ * @cache_level:	Which cache level defines scope of this resource
+ * @default_ctrl:	Specifies default cache cbm or memory B/W percent.
+ * @msr_base:		Base MSR address for CBMs
+ * @msr_update:		Function pointer to update QOS MSRs
+ * @data_width:		Character width of data when displaying
+ * @domains:		All domains for this resource
+ * @cache:		Cache allocation related data
+ * @format_str:		Per resource format string to show domain value
+ * @parse_ctrlval:	Per resource function pointer to parse control values
+ * @evt_list:			List of monitoring events
+ * @num_rmid:			Number of RMIDs available
+ * @mon_scale:			cqm counter * mon_scale = occupancy in bytes
+ * @fflags:			flags to choose base and info files
+ */
+struct rdt_resource {
+	int			rid;
+	bool			alloc_enabled;
+	bool			mon_enabled;
+	bool			alloc_capable;
+	bool			mon_capable;
+	char			*name;
+	int			num_closid;
+	int			cache_level;
+	u32			default_ctrl;
+	unsigned int		msr_base;
+	void (*msr_update)	(struct rdt_domain *d, struct msr_param *m,
+				 struct rdt_resource *r);
+	int			data_width;
+	struct list_head	domains;
+	struct rdt_cache	cache;
+	struct rdt_membw	membw;
+	const char		*format_str;
+	int (*parse_ctrlval)	(char *buf, struct rdt_resource *r,
+				 struct rdt_domain *d);
+	struct list_head	evt_list;
+	int			num_rmid;
+	unsigned int		mon_scale;
+	unsigned long		fflags;
+};
+
+int parse_cbm(char *buf, struct rdt_resource *r, struct rdt_domain *d);
+int parse_bw(char *buf, struct rdt_resource *r,  struct rdt_domain *d);
+
+extern struct mutex rdtgroup_mutex;
+
+extern struct rdt_resource rdt_resources_all[];
+extern struct rdtgroup rdtgroup_default;
+DECLARE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
+
+int __init rdtgroup_init(void);
+
+enum {
+	RDT_RESOURCE_L3,
+	RDT_RESOURCE_L3DATA,
+	RDT_RESOURCE_L3CODE,
+	RDT_RESOURCE_L2,
+	RDT_RESOURCE_MBA,
+
+	/* Must be the last */
+	RDT_NUM_RESOURCES,
+};
+
+#define for_each_capable_rdt_resource(r)				      \
+	for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
+	     r++)							      \
+		if (r->alloc_capable || r->mon_capable)
+
+#define for_each_alloc_capable_rdt_resource(r)				      \
+	for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
+	     r++)							      \
+		if (r->alloc_capable)
+
+#define for_each_mon_capable_rdt_resource(r)				      \
+	for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
+	     r++)							      \
+		if (r->mon_capable)
+
+#define for_each_alloc_enabled_rdt_resource(r)				      \
+	for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
+	     r++)							      \
+		if (r->alloc_enabled)
+
+#define for_each_mon_enabled_rdt_resource(r)				      \
+	for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
+	     r++)							      \
+		if (r->mon_enabled)
+
+/* CPUID.(EAX=10H, ECX=ResID=1).EAX */
+union cpuid_0x10_1_eax {
+	struct {
+		unsigned int cbm_len:5;
+	} split;
+	unsigned int full;
+};
+
+/* CPUID.(EAX=10H, ECX=ResID=3).EAX */
+union cpuid_0x10_3_eax {
+	struct {
+		unsigned int max_delay:12;
+	} split;
+	unsigned int full;
+};
+
+/* CPUID.(EAX=10H, ECX=ResID).EDX */
+union cpuid_0x10_x_edx {
+	struct {
+		unsigned int cos_max:16;
+	} split;
+	unsigned int full;
+};
+
+void rdt_ctrl_update(void *arg);
+struct rdtgroup *rdtgroup_kn_lock_live(struct kernfs_node *kn);
+void rdtgroup_kn_unlock(struct kernfs_node *kn);
+struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id,
+				   struct list_head **pos);
+ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
+				char *buf, size_t nbytes, loff_t off);
+int rdtgroup_schemata_show(struct kernfs_open_file *of,
+			   struct seq_file *s, void *v);
+struct rdt_domain *get_domain_from_cpu(int cpu, struct rdt_resource *r);
+int alloc_rmid(void);
+void free_rmid(u32 rmid);
+int rdt_get_mon_l3_config(struct rdt_resource *r);
+void mon_event_count(void *info);
+int rdtgroup_mondata_show(struct seq_file *m, void *arg);
+void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
+				    unsigned int dom_id);
+void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
+				    struct rdt_domain *d);
+void mon_event_read(struct rmid_read *rr, struct rdt_domain *d,
+		    struct rdtgroup *rdtgrp, int evtid, int first);
+void mbm_setup_overflow_handler(struct rdt_domain *dom,
+				unsigned long delay_ms);
+void mbm_handle_overflow(struct work_struct *work);
+void cqm_setup_limbo_handler(struct rdt_domain *dom, unsigned long delay_ms);
+void cqm_handle_limbo(struct work_struct *work);
+bool has_busy_rmid(struct rdt_resource *r, struct rdt_domain *d);
+void __check_limbo(struct rdt_domain *d, bool force_free);
+
+#endif /* _ASM_X86_INTEL_RDT_H */

arch/x86/kernel/cpu/intel_rdt_monitor.c

···
+/*
+ * Resource Director Technology(RDT)
+ * - Monitoring code
+ *
+ * Copyright (C) 2017 Intel Corporation
+ *
+ * Author:
+ *    Vikas Shivappa <[e-mail]>
+ *
+ * This replaces the cqm.c based on perf but we reuse a lot of
+ * code and datastructures originally from Peter Zijlstra and Matt Fleming.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * More information about RDT be found in the Intel (R) x86 Architecture
+ * Software Developer Manual June 2016, volume 3, section 17.17.
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <asm/cpu_device_id.h>
+#include "intel_rdt.h"
+
+#define MSR_IA32_QM_CTR		0x0c8e
+#define MSR_IA32_QM_EVTSEL		0x0c8d
+
+struct rmid_entry {
+	u32				rmid;
+	int				busy;
+	struct list_head		list;
+};
+
+/**
+ * @rmid_free_lru    A least recently used list of free RMIDs
+ *     These RMIDs are guaranteed to have an occupancy less than the
+ *     threshold occupancy
+ */
+static LIST_HEAD(rmid_free_lru);
+
+/**
+ * @rmid_limbo_count     count of currently unused but (potentially)
+ *     dirty RMIDs.
+ *     This counts RMIDs that no one is currently using but that
+ *     may have a occupancy value > intel_cqm_threshold. User can change
+ *     the threshold occupancy value.
+ */
+unsigned int rmid_limbo_count;
+
+/**
+ * @rmid_entry - The entry in the limbo and free lists.
+ */
+static struct rmid_entry	*rmid_ptrs;
+
+/*
+ * Global boolean for rdt_monitor which is true if any
+ * resource monitoring is enabled.
+ */
+bool rdt_mon_capable;
+
+/*
+ * Global to indicate which monitoring events are enabled.
+ */
+unsigned int rdt_mon_features;
+
+/*
+ * This is the threshold cache occupancy at which we will consider an
+ * RMID available for re-allocation.
+ */
+unsigned int intel_cqm_threshold;
+
+static inline struct rmid_entry *__rmid_entry(u32 rmid)
+{
+	struct rmid_entry *entry;
+
+	entry = &rmid_ptrs[rmid];
+	WARN_ON(entry->rmid != rmid);
+
+	return entry;
+}
+
+static u64 __rmid_read(u32 rmid, u32 eventid)
+{
+	u64 val;
+
+	/*
+	 * As per the SDM, when IA32_QM_EVTSEL.EvtID (bits 7:0) is configured
+	 * with a valid event code for supported resource type and the bits
+	 * IA32_QM_EVTSEL.RMID (bits 41:32) are configured with valid RMID,
+	 * IA32_QM_CTR.data (bits 61:0) reports the monitored data.
+	 * IA32_QM_CTR.Error (bit 63) and IA32_QM_CTR.Unavailable (bit 62)
+	 * are error bits.
+	 */
+	wrmsr(MSR_IA32_QM_EVTSEL, eventid, rmid);
+	rdmsrl(MSR_IA32_QM_CTR, val);
+
+	return val;
+}
+
+static bool rmid_dirty(struct rmid_entry *entry)
+{
+	u64 val = __rmid_read(entry->rmid, QOS_L3_OCCUP_EVENT_ID);
+
+	return val >= intel_cqm_threshold;
+}
+
+/*
+ * Check the RMIDs that are marked as busy for this domain. If the
+ * reported LLC occupancy is below the threshold clear the busy bit and
+ * decrement the count. If the busy count gets to zero on an RMID, we
+ * free the RMID
+ */
+void __check_limbo(struct rdt_domain *d, bool force_free)
+{
+	struct rmid_entry *entry;
+	struct rdt_resource *r;
+	u32 crmid = 1, nrmid;
+
+	r = &rdt_resources_all[RDT_RESOURCE_L3];
+
+	/*
+	 * Skip RMID 0 and start from RMID 1 and check all the RMIDs that
+	 * are marked as busy for occupancy < threshold. If the occupancy
+	 * is less than the threshold decrement the busy counter of the
+	 * RMID and move it to the free list when the counter reaches 0.
+	 */
+	for (;;) {
+		nrmid = find_next_bit(d->rmid_busy_llc, r->num_rmid, crmid);
+		if (nrmid >= r->num_rmid)
+			break;
+
+		entry = __rmid_entry(nrmid);
+		if (force_free || !rmid_dirty(entry)) {
+			clear_bit(entry->rmid, d->rmid_busy_llc);
+			if (!--entry->busy) {
+				rmid_limbo_count--;
+				list_add_tail(&entry->list, &rmid_free_lru);
+			}
+		}
+		crmid = nrmid + 1;
+	}
+}
+
+bool has_busy_rmid(struct rdt_resource *r, struct rdt_domain *d)
+{
+	return find_first_bit(d->rmid_busy_llc, r->num_rmid) != r->num_rmid;
+}
+
+/*
+ * As of now the RMIDs allocation is global.
+ * However we keep track of which packages the RMIDs
+ * are used to optimize the limbo list management.
+ */
+int alloc_rmid(void)
+{
+	struct rmid_entry *entry;
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	if (list_empty(&rmid_free_lru))
+		return rmid_limbo_count ? -EBUSY : -ENOSPC;
+
+	entry = list_first_entry(&rmid_free_lru,
+				 struct rmid_entry, list);
+	list_del(&entry->list);
+
+	return entry->rmid;
+}
+
+static void add_rmid_to_limbo(struct rmid_entry *entry)
+{
+	struct rdt_resource *r;
+	struct rdt_domain *d;
+	int cpu;
+	u64 val;
+
+	r = &rdt_resources_all[RDT_RESOURCE_L3];
+
+	entry->busy = 0;
+	cpu = get_cpu();
+	list_for_each_entry(d, &r->domains, list) {
+		if (cpumask_test_cpu(cpu, &d->cpu_mask)) {
+			val = __rmid_read(entry->rmid, QOS_L3_OCCUP_EVENT_ID);
+			if (val <= intel_cqm_threshold)
+				continue;
+		}
+
+		/*
+		 * For the first limbo RMID in the domain,
+		 * setup up the limbo worker.
+		 */
+		if (!has_busy_rmid(r, d))
+			cqm_setup_limbo_handler(d, CQM_LIMBOCHECK_INTERVAL);
+		set_bit(entry->rmid, d->rmid_busy_llc);
+		entry->busy++;
+	}
+	put_cpu();
+
+	if (entry->busy)
+		rmid_limbo_count++;
+	else
+		list_add_tail(&entry->list, &rmid_free_lru);
+}
+
+void free_rmid(u32 rmid)
+{
+	struct rmid_entry *entry;
+
+	if (!rmid)
+		return;
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	entry = __rmid_entry(rmid);
+
+	if (is_llc_occupancy_enabled())
+		add_rmid_to_limbo(entry);
+	else
+		list_add_tail(&entry->list, &rmid_free_lru);
+}
+
+static int __mon_event_count(u32 rmid, struct rmid_read *rr)
+{
+	u64 chunks, shift, tval;
+	struct mbm_state *m;
+
+	tval = __rmid_read(rmid, rr->evtid);
+	if (tval & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL)) {
+		rr->val = tval;
+		return -EINVAL;
+	}
+	switch (rr->evtid) {
+	case QOS_L3_OCCUP_EVENT_ID:
+		rr->val += tval;
+		return 0;
+	case QOS_L3_MBM_TOTAL_EVENT_ID:
+		m = &rr->d->mbm_total[rmid];
+		break;
+	case QOS_L3_MBM_LOCAL_EVENT_ID:
+		m = &rr->d->mbm_local[rmid];
+		break;
+	default:
+		/*
+		 * Code would never reach here because
+		 * an invalid event id would fail the __rmid_read.
+		 */
+		return -EINVAL;
+	}
+
+	if (rr->first) {
+		m->prev_msr = tval;
+		m->chunks = 0;
+		return 0;
+	}
+
+	shift = 64 - MBM_CNTR_WIDTH;
+	chunks = (tval << shift) - (m->prev_msr << shift);
+	chunks >>= shift;
+	m->chunks += chunks;
+	m->prev_msr = tval;
+
+	rr->val += m->chunks;
+	return 0;
+}
+
+/*
+ * This is called via IPI to read the CQM/MBM counters
+ * on a domain.
+ */
+void mon_event_count(void *info)
+{
+	struct rdtgroup *rdtgrp, *entry;
+	struct rmid_read *rr = info;
+	struct list_head *head;
+
+	rdtgrp = rr->rgrp;
+
+	if (__mon_event_count(rdtgrp->mon.rmid, rr))
+		return;
+
+	/*
+	 * For Ctrl groups read data from child monitor groups.
+	 */
+	head = &rdtgrp->mon.crdtgrp_list;
+
+	if (rdtgrp->type == RDTCTRL_GROUP) {
+		list_for_each_entry(entry, head, mon.crdtgrp_list) {
+			if (__mon_event_count(entry->mon.rmid, rr))
+				return;
+		}
+	}
+}
+
+static void mbm_update(struct rdt_domain *d, int rmid)
+{
+	struct rmid_read rr;
+
+	rr.first = false;
+	rr.d = d;
+
+	/*
+	 * This is protected from concurrent reads from user
+	 * as both the user and we hold the global mutex.
+	 */
+	if (is_mbm_total_enabled()) {
+		rr.evtid = QOS_L3_MBM_TOTAL_EVENT_ID;
+		__mon_event_count(rmid, &rr);
+	}
+	if (is_mbm_local_enabled()) {
+		rr.evtid = QOS_L3_MBM_LOCAL_EVENT_ID;
+		__mon_event_count(rmid, &rr);
+	}
+}
+
+/*
+ * Handler to scan the limbo list and move the RMIDs
+ * to free list whose occupancy < threshold_occupancy.
+ */
+void cqm_handle_limbo(struct work_struct *work)
+{
+	unsigned long delay = msecs_to_jiffies(CQM_LIMBOCHECK_INTERVAL);
+	int cpu = smp_processor_id();
+	struct rdt_resource *r;
+	struct rdt_domain *d;
+
+	mutex_lock(&rdtgroup_mutex);
+
+	r = &rdt_resources_all[RDT_RESOURCE_L3];
+	d = get_domain_from_cpu(cpu, r);
+
+	if (!d) {
+		pr_warn_once("Failure to get domain for limbo worker\n");
+		goto out_unlock;
+	}
+
+	__check_limbo(d, false);
+
+	if (has_busy_rmid(r, d))
+		schedule_delayed_work_on(cpu, &d->cqm_limbo, delay);
+
+out_unlock:
+	mutex_unlock(&rdtgroup_mutex);
+}
+
+void cqm_setup_limbo_handler(struct rdt_domain *dom, unsigned long delay_ms)
+{
+	unsigned long delay = msecs_to_jiffies(delay_ms);
+	struct rdt_resource *r;
+	int cpu;
+
+	r = &rdt_resources_all[RDT_RESOURCE_L3];
+
+	cpu = cpumask_any(&dom->cpu_mask);
+	dom->cqm_work_cpu = cpu;
+
+	schedule_delayed_work_on(cpu, &dom->cqm_limbo, delay);
+}
+
+void mbm_handle_overflow(struct work_struct *work)
+{
+	unsigned long delay = msecs_to_jiffies(MBM_OVERFLOW_INTERVAL);
+	struct rdtgroup *prgrp, *crgrp;
+	int cpu = smp_processor_id();
+	struct list_head *head;
+	struct rdt_domain *d;
+
+	mutex_lock(&rdtgroup_mutex);
+
+	if (!static_branch_likely(&rdt_enable_key))
+		goto out_unlock;
+
+	d = get_domain_from_cpu(cpu, &rdt_resources_all[RDT_RESOURCE_L3]);
+	if (!d)
+		goto out_unlock;
+
+	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
+		mbm_update(d, prgrp->mon.rmid);
+
+		head = &prgrp->mon.crdtgrp_list;
+		list_for_each_entry(crgrp, head, mon.crdtgrp_list)
+			mbm_update(d, crgrp->mon.rmid);
+	}
+
+	schedule_delayed_work_on(cpu, &d->mbm_over, delay);
+
+out_unlock:
+	mutex_unlock(&rdtgroup_mutex);
+}
+
+void mbm_setup_overflow_handler(struct rdt_domain *dom, unsigned long delay_ms)
+{
+	unsigned long delay = msecs_to_jiffies(delay_ms);
+	int cpu;
+
+	if (!static_branch_likely(&rdt_enable_key))
+		return;
+	cpu = cpumask_any(&dom->cpu_mask);
+	dom->mbm_work_cpu = cpu;
+	schedule_delayed_work_on(cpu, &dom->mbm_over, delay);
+}
+
+static int dom_data_init(struct rdt_resource *r)
+{
+	struct rmid_entry *entry = NULL;
+	int i, nr_rmids;
+
+	nr_rmids = r->num_rmid;
+	rmid_ptrs = kcalloc(nr_rmids, sizeof(struct rmid_entry), GFP_KERNEL);
+	if (!rmid_ptrs)
+		return -ENOMEM;
+
+	for (i = 0; i < nr_rmids; i++) {
+		entry = &rmid_ptrs[i];
+		INIT_LIST_HEAD(&entry->list);
+
+		entry->rmid = i;
+		list_add_tail(&entry->list, &rmid_free_lru);
+	}
+
+	/*
+	 * RMID 0 is special and is always allocated. It's used for all
+	 * tasks that are not monitored.
+	 */
+	entry = __rmid_entry(0);
+	list_del(&entry->list);
+
+	return 0;
+}
+
+static struct mon_evt llc_occupancy_event = {
+	.name		= "llc_occupancy",
+	.evtid		= QOS_L3_OCCUP_EVENT_ID,
+};
+
+static struct mon_evt mbm_total_event = {
+	.name		= "mbm_total_bytes",
+	.evtid		= QOS_L3_MBM_TOTAL_EVENT_ID,
+};
+
+static struct mon_evt mbm_local_event = {
+	.name		= "mbm_local_bytes",
+	.evtid		= QOS_L3_MBM_LOCAL_EVENT_ID,
+};
+
+/*
+ * Initialize the event list for the resource.
+ *
+ * Note that MBM events are also part of RDT_RESOURCE_L3 resource
+ * because as per the SDM the total and local memory bandwidth
+ * are enumerated as part of L3 monitoring.
+ */
+static void l3_mon_evt_init(struct rdt_resource *r)
+{
+	INIT_LIST_HEAD(&r->evt_list);
+
+	if (is_llc_occupancy_enabled())
+		list_add_tail(&llc_occupancy_event.list, &r->evt_list);
+	if (is_mbm_total_enabled())
+		list_add_tail(&mbm_total_event.list, &r->evt_list);
+	if (is_mbm_local_enabled())
+		list_add_tail(&mbm_local_event.list, &r->evt_list);
+}
+
+int rdt_get_mon_l3_config(struct rdt_resource *r)
+{
+	int ret;
+
+	r->mon_scale = boot_cpu_data.x86_cache_occ_scale;
+	r->num_rmid = boot_cpu_data.x86_cache_max_rmid + 1;
+
+	/*
+	 * A reasonable upper limit on the max threshold is the number
+	 * of lines tagged per RMID if all RMIDs have the same number of
+	 * lines tagged in the LLC.
+	 *
+	 * For a 35MB LLC and 56 RMIDs, this is ~1.8% of the LLC.
+	 */
+	intel_cqm_threshold = boot_cpu_data.x86_cache_size * 1024 / r->num_rmid;
+
+	/* h/w works in units of "boot_cpu_data.x86_cache_occ_scale" */
+	intel_cqm_threshold /= r->mon_scale;
+
+	ret = dom_data_init(r);
+	if (ret)
+		return ret;
+
+	l3_mon_evt_init(r);
+
+	r->mon_capable = true;
+	r->mon_enabled = true;
+
+	return 0;
+}

arch/x86/kernel/cpu/intel_rdt_rdtgroup.c

···
 
 #include <uapi/linux/magic.h>
 
-#include <asm/intel_rdt.h>
-#include <asm/intel_rdt_common.h>
+#include <asm/intel_rdt_sched.h>
+#include "intel_rdt.h"
 
 DEFINE_STATIC_KEY_FALSE(rdt_enable_key);
-struct kernfs_root *rdt_root;
+DEFINE_STATIC_KEY_FALSE(rdt_mon_enable_key);
+DEFINE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
+static struct kernfs_root *rdt_root;
 struct rdtgroup rdtgroup_default;
 LIST_HEAD(rdt_all_groups);
 
 /* Kernel fs node for "info" directory under root */
 static struct kernfs_node *kn_info;
+
+/* Kernel fs node for "mon_groups" directory under root */
+static struct kernfs_node *kn_mongrp;
+
+/* Kernel fs node for "mon_data" directory under root */
+static struct kernfs_node *kn_mondata;
 
 /*
  * Trivial allocator for CLOSIDs. Since h/w only supports a small number,
···
 	int rdt_min_closid = 32;
 
 	/* Compute rdt_min_closid across all resources */
-	for_each_enabled_rdt_resource(r)
+	for_each_alloc_enabled_rdt_resource(r)
 		rdt_min_closid = min(rdt_min_closid, r->num_closid);
 
 	closid_free_map = BIT_MASK(rdt_min_closid) - 1;
···
 	closid_free_map &= ~1;
 }
 
-int closid_alloc(void)
+static int closid_alloc(void)
 {
-	int closid = ffs(closid_free_map);
+	u32 closid = ffs(closid_free_map);
 
 	if (closid == 0)
 		return -ENOSPC;
···
 	return 0;
 }
 
-static int rdtgroup_add_files(struct kernfs_node *kn, struct rftype *rfts,
-			      int len)
-{
-	struct rftype *rft;
-	int ret;
-
-	lockdep_assert_held(&rdtgroup_mutex);
-
-	for (rft = rfts; rft < rfts + len; rft++) {
-		ret = rdtgroup_add_file(kn, rft);
-		if (ret)
-			goto error;
-	}
-
-	return 0;
-error:
-	pr_warn("Failed to add %s, err=%d\n", rft->name, ret);
-	while (--rft >= rfts)
-		kernfs_remove_by_name(kn, rft->name);
-	return ret;
-}
-
 static int rdtgroup_seqfile_show(struct seq_file *m, void *arg)
 {
 	struct kernfs_open_file *of = m->private;
···
 	.atomic_write_len	= PAGE_SIZE,
 	.write			= rdtgroup_file_write,
 	.seq_show		= rdtgroup_seqfile_show,
+};
+
+static struct kernfs_ops kf_mondata_ops = {
+	.atomic_write_len	= PAGE_SIZE,
+	.seq_show		= rdtgroup_mondata_show,
 };
 
 static bool is_cpu_list(struct kernfs_open_file *of)
···
 /*
  * This is safe against intel_rdt_sched_in() called from __switch_to()
  * because __switch_to() is executed with interrupts disabled. A local call
- * from rdt_update_closid() is proteced against __switch_to() because
+ * from update_closid_rmid() is proteced against __switch_to() because
  * preemption is disabled.
  */
-static void rdt_update_cpu_closid(void *closid)
+static void update_cpu_closid_rmid(void *info)
 {
-	if (closid)
-		this_cpu_write(cpu_closid, *(int *)closid);
+	struct rdtgroup *r = info;
+
+	if (r) {
+		this_cpu_write(pqr_state.default_closid, r->closid);
+		this_cpu_write(pqr_state.default_rmid, r->mon.rmid);
+	}
+
 	/*
 	 * We cannot unconditionally write the MSR because the current
 	 * executing task might have its own closid selected. Just reuse
···
 /*
  * Update the PGR_ASSOC MSR on all cpus in @cpu_mask,
  *
- * Per task closids must have been set up before calling this function.
- *
- * The per cpu closids are updated with the smp function call, when @closid
- * is not NULL. If @closid is NULL then all affected percpu closids must
- * have been set up before calling this function.
+ * Per task closids/rmids must have been set up before calling this function.
  */
 static void
-rdt_update_closid(const struct cpumask *cpu_mask, int *closid)
+update_closid_rmid(const struct cpumask *cpu_mask, struct rdtgroup *r)
 {
 	int cpu = get_cpu();
 
 	if (cpumask_test_cpu(cpu, cpu_mask))
-		rdt_update_cpu_closid(closid);
-	smp_call_function_many(cpu_mask, rdt_update_cpu_closid, closid, 1);
+		update_cpu_closid_rmid(r);
+	smp_call_function_many(cpu_mask, update_cpu_closid_rmid, r, 1);
 	put_cpu();
+}
+
+static int cpus_mon_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask,
+			  cpumask_var_t tmpmask)
+{
+	struct rdtgroup *prgrp = rdtgrp->mon.parent, *crgrp;
+	struct list_head *head;
+
+	/* Check whether cpus belong to parent ctrl group */
+	cpumask_andnot(tmpmask, newmask, &prgrp->cpu_mask);
+	if (cpumask_weight(tmpmask))
+		return -EINVAL;
+
+	/* Check whether cpus are dropped from this group */
+	cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask);
+	if (cpumask_weight(tmpmask)) {
+		/* Give any dropped cpus to parent rdtgroup */
+		cpumask_or(&prgrp->cpu_mask, &prgrp->cpu_mask, tmpmask);
+		update_closid_rmid(tmpmask, prgrp);
+	}
+
+	/*
+	 * If we added cpus, remove them from previous group that owned them
+	 * and update per-cpu rmid
+	 */
+	cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask);
+	if (cpumask_weight(tmpmask)) {
+		head = &prgrp->mon.crdtgrp_list;
+		list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
+			if (crgrp == rdtgrp)
+				continue;
+			cpumask_andnot(&crgrp->cpu_mask, &crgrp->cpu_mask,
+				       tmpmask);
+		}
+		update_closid_rmid(tmpmask, rdtgrp);
+	}
+
+	/* Done pushing/pulling - update this group with new mask */
+	cpumask_copy(&rdtgrp->cpu_mask, newmask);
+
+	return 0;
+}
+
+static void cpumask_rdtgrp_clear(struct rdtgroup *r, struct cpumask *m)
+{
+	struct rdtgroup *crgrp;
+
+	cpumask_andnot(&r->cpu_mask, &r->cpu_mask, m);
+	/* update the child mon group masks as well*/
+	list_for_each_entry(crgrp, &r->mon.crdtgrp_list, mon.crdtgrp_list)
+		cpumask_and(&crgrp->cpu_mask, &r->cpu_mask, &crgrp->cpu_mask);
+}
+
+static int cpus_ctrl_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask,
+			   cpumask_var_t tmpmask, cpumask_var_t tmpmask1)
+{
+	struct rdtgroup *r, *crgrp;
+	struct list_head *head;
+
+	/* Check whether cpus are dropped from this group */
+	cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask);
+	if (cpumask_weight(tmpmask)) {
+		/* Can't drop from default group */
+		if (rdtgrp == &rdtgroup_default)
+			return -EINVAL;
+
+		/* Give any dropped cpus to rdtgroup_default */
+		cpumask_or(&rdtgroup_default.cpu_mask,
+			   &rdtgroup_default.cpu_mask, tmpmask);
+		update_closid_rmid(tmpmask, &rdtgroup_default);
+	}
+
+	/*
+	 * If we added cpus, remove them from previous group and
+	 * the prev group's child groups that owned them
+	 * and update per-cpu closid/rmid.
+	 */
+	cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask);
+	if (cpumask_weight(tmpmask)) {
+		list_for_each_entry(r, &rdt_all_groups, rdtgroup_list) {
+			if (r == rdtgrp)
+				continue;
+			cpumask_and(tmpmask1, &r->cpu_mask, tmpmask);
+			if (cpumask_weight(tmpmask1))
+				cpumask_rdtgrp_clear(r, tmpmask1);
+		}
+		update_closid_rmid(tmpmask, rdtgrp);
+	}
+
+	/* Done pushing/pulling - update this group with new mask */
+	cpumask_copy(&rdtgrp->cpu_mask, newmask);
+
+	/*
+	 * Clear child mon group masks since there is a new parent mask
+	 * now and update the rmid for the cpus the child lost.
+	 */
+	head = &rdtgrp->mon.crdtgrp_list;
+	list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
+		cpumask_and(tmpmask, &rdtgrp->cpu_mask, &crgrp->cpu_mask);
+		update_closid_rmid(tmpmask, rdtgrp);
+		cpumask_clear(&crgrp->cpu_mask);
+	}
+
+	return 0;
 }
 
 static ssize_t rdtgroup_cpus_write(struct kernfs_open_file *of,
 				   char *buf, size_t nbytes, loff_t off)
 {
-	cpumask_var_t tmpmask, newmask;
-	struct rdtgroup *rdtgrp, *r;
+	cpumask_var_t tmpmask, newmask, tmpmask1;
+	struct rdtgroup *rdtgrp;
 	int ret;
 
 	if (!buf)
···
 		return -ENOMEM;
 	if (!zalloc_cpumask_var(&newmask, GFP_KERNEL)) {
 		free_cpumask_var(tmpmask);
+		return -ENOMEM;
+	}
+	if (!zalloc_cpumask_var(&tmpmask1, GFP_KERNEL)) {
+		free_cpumask_var(tmpmask);
+		free_cpumask_var(newmask);
 		return -ENOMEM;
 	}
 
···
 		goto unlock;
 	}
 
-	/* Check whether cpus are dropped from this group */
-	cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask);
-	if (cpumask_weight(tmpmask)) {
-		/* Can't drop from default group */
-		if (rdtgrp == &rdtgroup_default) {
-			ret = -EINVAL;
-			goto unlock;
-		}
-		/* Give any dropped cpus to rdtgroup_default */
-		cpumask_or(&rdtgroup_default.cpu_mask,
-			   &rdtgroup_default.cpu_mask, tmpmask);
-		rdt_update_closid(tmpmask, &rdtgroup_default.closid);
-	}
-
-	/*
-	 * If we added cpus, remove them from previous group that owned them
-	 * and update per-cpu closid
-	 */
-	cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask);
-	if (cpumask_weight(tmpmask)) {
-		list_for_each_entry(r, &rdt_all_groups, rdtgroup_list) {
-			if (r == rdtgrp)
-				continue;
-			cpumask_andnot(&r->cpu_mask, &r->cpu_mask, tmpmask);
-		}
-		rdt_update_closid(tmpmask, &rdtgrp->closid);
-	}
-
-	/* Done pushing/pulling - update this group with new mask */
-	cpumask_copy(&rdtgrp->cpu_mask, newmask);
+	if (rdtgrp->type == RDTCTRL_GROUP)
+		ret = cpus_ctrl_write(rdtgrp, newmask, tmpmask, tmpmask1);
+	else if (rdtgrp->type == RDTMON_GROUP)
+		ret = cpus_mon_write(rdtgrp, newmask, tmpmask);
+	else
+		ret = -EINVAL;
 
 unlock:
 	rdtgroup_kn_unlock(of->kn);
 	free_cpumask_var(tmpmask);
 	free_cpumask_var(newmask);
+	free_cpumask_var(tmpmask1);
 
 	return ret ?: nbytes;
 }
···
 	if (atomic_dec_and_test(&rdtgrp->waitcount) &&
 	    (rdtgrp->flags & RDT_DELETED)) {
 		current->closid = 0;
+		current->rmid = 0;
 		kfree(rdtgrp);
 	}
 
···
 		atomic_dec(&rdtgrp->waitcount);
 		kfree(callback);
 	} else {
-		tsk->closid = rdtgrp->closid;
+		/*
+		 * For ctrl_mon groups move both closid and rmid.
+		 * For monitor groups, can move the tasks only from
+		 * their parent CTRL group.
+		 */
+		if (rdtgrp->type == RDTCTRL_GROUP) {
+			tsk->closid = rdtgrp->closid;
+			tsk->rmid = rdtgrp->mon.rmid;
+		} else if (rdtgrp->type == RDTMON_GROUP) {
+			if (rdtgrp->mon.parent->closid == tsk->closid)
+				tsk->rmid = rdtgrp->mon.rmid;
+			else
+				ret = -EINVAL;
+		}
 	}
 	return ret;
 }
···
 
 	rcu_read_lock();
 	for_each_process_thread(p, t) {
-		if (t->closid == r->closid)
+		if ((r->type == RDTCTRL_GROUP && t->closid == r->closid) ||
+		    (r->type == RDTMON_GROUP && t->rmid == r->mon.rmid))
 			seq_printf(s, "%d\n", t->pid);
 	}
 	rcu_read_unlock();
···
 
 	return ret;
 }
-
-/* Files in each rdtgroup */
-static struct rftype rdtgroup_base_files[] = {
-	{
-		.name		= "cpus",
-		.mode		= 0644,
-		.kf_ops		= &rdtgroup_kf_single_ops,
-		.write		= rdtgroup_cpus_write,
-		.seq_show	= rdtgroup_cpus_show,
-	},
-	{
-		.name		= "cpus_list",
-		.mode		= 0644,
-		.kf_ops		= &rdtgroup_kf_single_ops,
-		.write		= rdtgroup_cpus_write,
-		.seq_show	= rdtgroup_cpus_show,
-		.flags		= RFTYPE_FLAGS_CPUS_LIST,
-	},
-	{
-		.name		= "tasks",
-		.mode		= 0644,
-		.kf_ops		= &rdtgroup_kf_single_ops,
-		.write		= rdtgroup_tasks_write,
-		.seq_show	= rdtgroup_tasks_show,
-	},
-	{
-		.name		= "schemata",
-		.mode		= 0644,
-		.kf_ops		= &rdtgroup_kf_single_ops,
-		.write		= rdtgroup_schemata_write,
-		.seq_show	= rdtgroup_schemata_show,
-	},
-};
 
 static int rdt_num_closids_show(struct kernfs_open_file *of,
 				struct seq_file *seq, void *v)
···
 	return 0;
 }
 
+static int rdt_shareable_bits_show(struct kernfs_open_file *of,
+				   struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	seq_printf(seq, "%x\n", r->cache.shareable_bits);
+	return 0;
+}
+
 static int rdt_min_bw_show(struct kernfs_open_file *of,
 			     struct seq_file *seq, void *v)
 {
 	struct rdt_resource *r = of->kn->parent->priv;
 
 	seq_printf(seq, "%u\n", r->membw.min_bw);
+	return 0;
+}
+
+static int rdt_num_rmids_show(struct kernfs_open_file *of,
+			      struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	seq_printf(seq, "%d\n", r->num_rmid);
+
+	return 0;
+}
+
+static int rdt_mon_features_show(struct kernfs_open_file *of,
+				 struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+	struct mon_evt *mevt;
+
+	list_for_each_entry(mevt, &r->evt_list, list)
+		seq_printf(seq, "%s\n", mevt->name);
+
 	return 0;
 }
 
···
 	return 0;
 }
 
+static int max_threshold_occ_show(struct kernfs_open_file *of,
+				  struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	seq_printf(seq, "%u\n", intel_cqm_threshold * r->mon_scale);
+
+	return 0;
+}
+
+static ssize_t max_threshold_occ_write(struct kernfs_open_file *of,
+				       char *buf, size_t nbytes, loff_t off)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+	unsigned int bytes;
+	int ret;
+
+	ret = kstrtouint(buf, 0, &bytes);
+	if (ret)
+		return ret;
+
+	if (bytes > (boot_cpu_data.x86_cache_size * 1024))
+		return -EINVAL;
+
+	intel_cqm_threshold = bytes / r->mon_scale;
+
+	return nbytes;
+}
+
 /* rdtgroup information files for one cache resource. */
-static struct rftype res_cache_info_files[] = {
+static struct rftype res_common_files[] = {
 	{
 		.name		= "num_closids",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_num_closids_show,
+		.fflags		= RF_CTRL_INFO,
+	},
+	{
+		.name		= "mon_features",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_mon_features_show,
+		.fflags		= RF_MON_INFO,
+	},
+	{
+		.name		= "num_rmids",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_num_rmids_show,
+		.fflags		= RF_MON_INFO,
 	},
 	{
 		.name		= "cbm_mask",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_default_ctrl_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
 	},
 	{
 		.name		= "min_cbm_bits",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_min_cbm_bits_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
 	},
-};
-
-/* rdtgroup information files for memory bandwidth. */
-static struct rftype res_mba_info_files[] = {
 	{
-		.name		= "num_closids",
+		.name		= "shareable_bits",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
-		.seq_show	= rdt_num_closids_show,
+		.seq_show	= rdt_shareable_bits_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
 	},
 	{
 		.name		= "min_bandwidth",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_min_bw_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_MB,
 	},
 	{
 		.name		= "bandwidth_gran",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_bw_gran_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_MB,
 	},
 	{
 		.name		= "delay_linear",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_delay_linear_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_MB,
+	},
+	{
+		.name		= "max_threshold_occupancy",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= max_threshold_occ_write,
+		.seq_show	= max_threshold_occ_show,
+		.fflags		= RF_MON_INFO | RFTYPE_RES_CACHE,
+	},
+	{
+		.name		= "cpus",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_cpus_write,
+		.seq_show	= rdtgroup_cpus_show,
+		.fflags		= RFTYPE_BASE,
+	},
+	{
+		.name		= "cpus_list",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_cpus_write,
+		.seq_show	= rdtgroup_cpus_show,
+		.flags		= RFTYPE_FLAGS_CPUS_LIST,
+		.fflags		= RFTYPE_BASE,
+	},
+	{
+		.name		= "tasks",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_tasks_write,
+		.seq_show	= rdtgroup_tasks_show,
+		.fflags		= RFTYPE_BASE,
+	},
+	{
+		.name		= "schemata",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_schemata_write,
+		.seq_show	= rdtgroup_schemata_show,
+		.fflags		= RF_CTRL_BASE,
 	},
 };
 
-void rdt_get_mba_infofile(struct rdt_resource *r)
+static int rdtgroup_add_files(struct kernfs_node *kn, unsigned long fflags)
 {
-	r->info_files = res_mba_info_files;
-	r->nr_info_files = ARRAY_SIZE(res_mba_info_files);
+	struct rftype *rfts, *rft;
+	int ret, len;
+
+	rfts = res_common_files;
+	len = ARRAY_SIZE(res_common_files);
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	for (rft = rfts; rft < rfts + len; rft++) {
+		if ((fflags & rft->fflags) == rft->fflags) {
+			ret = rdtgroup_add_file(kn, rft);
+			if (ret)
+				goto error;
+		}
+	}
+
+	return 0;
+error:
+	pr_warn("Failed to add %s, err=%d\n", rft->name, ret);
+	while (--rft >= rfts) {
+		if ((fflags & rft->fflags) == rft->fflags)
+			kernfs_remove_by_name(kn, rft->name);
+	}
+	return ret;
 }
 
-void rdt_get_cache_infofile(struct rdt_resource *r)
+static int rdtgroup_mkdir_info_resdir(struct rdt_resource *r, char *name,
+				      unsigned long fflags)
 {
-	r->info_files = res_cache_info_files;
-	r->nr_info_files = ARRAY_SIZE(res_cache_info_files);
+	struct kernfs_node *kn_subdir;
+	int ret;
+
+	kn_subdir = kernfs_create_dir(kn_info, name,
+				      kn_info->mode, r);
+	if (IS_ERR(kn_subdir))
+		return PTR_ERR(kn_subdir);
+
+	kernfs_get(kn_subdir);
+	ret = rdtgroup_kn_set_ugid(kn_subdir);
+	if (ret)
+		return ret;
+
+	ret = rdtgroup_add_files(kn_subdir, fflags);
+	if (!ret)
+		kernfs_activate(kn_subdir);
+
+	return ret;
 }
 
 static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn)
 {
-	struct kernfs_node *kn_subdir;
-	struct rftype *res_info_files;
 	struct rdt_resource *r;
-	int ret, len;
+	unsigned long fflags;
+	char name[32];
+	int ret;
 
 	/* create the directory */
 	kn_info = kernfs_create_dir(parent_kn, "info", parent_kn->mode, NULL);
···
 		return PTR_ERR(kn_info);
 	kernfs_get(kn_info);
 
-	for_each_enabled_rdt_resource(r) {
-		kn_subdir = kernfs_create_dir(kn_info, r->name,
-					      kn_info->mode, r);
-		if (IS_ERR(kn_subdir)) {
-			ret = PTR_ERR(kn_subdir);
-			goto out_destroy;
-		}
-		kernfs_get(kn_subdir);
-		ret = rdtgroup_kn_set_ugid(kn_subdir);
+	for_each_alloc_enabled_rdt_resource(r) {
+		fflags =  r->fflags | RF_CTRL_INFO;
+		ret = rdtgroup_mkdir_info_resdir(r, r->name, fflags);
 		if (ret)
 			goto out_destroy;
+	}
 
-		res_info_files = r->info_files;
-		len = r->nr_info_files;
-
-		ret = rdtgroup_add_files(kn_subdir, res_info_files, len);
+	for_each_mon_enabled_rdt_resource(r) {
+		fflags =  r->fflags | RF_MON_INFO;
+		sprintf(name, "%s_MON", r->name);
+		ret = rdtgroup_mkdir_info_resdir(r, name, fflags);
 		if (ret)
 			goto out_destroy;
-		kernfs_activate(kn_subdir);
 	}
 
 	/*
···
 	return ret;
 }
 
+static int
+mongroup_create_dir(struct kernfs_node *parent_kn, struct rdtgroup *prgrp,
+		    char *name, struct kernfs_node **dest_kn)
+{
+	struct kernfs_node *kn;
+	int ret;
+
+	/* create the directory */
+	kn = kernfs_create_dir(parent_kn, name, parent_kn->mode, prgrp);
+	if (IS_ERR(kn))
+		return PTR_ERR(kn);
+
+	if (dest_kn)
+		*dest_kn = kn;
+
+	/*
+	 * This extra ref will be put in kernfs_remove() and guarantees
+	 * that @rdtgrp->kn is always accessible.
+	 */
+	kernfs_get(kn);
+
+	ret = rdtgroup_kn_set_ugid(kn);
+	if (ret)
+		goto out_destroy;
+
+	kernfs_activate(kn);
+
+	return 0;
+
+out_destroy:
+	kernfs_remove(kn);
+	return ret;
+}
 static void l3_qos_cfg_update(void *arg)
 {
 	bool *enable = arg;
···
 	struct rdt_resource *r_l3 = &rdt_resources_all[RDT_RESOURCE_L3];
 	int ret;
 
-	if (!r_l3->capable || !r_l3data->capable || !r_l3code->capable)
+	if (!r_l3->alloc_capable || !r_l3data->alloc_capable ||
+	    !r_l3code->alloc_capable)
 		return -EINVAL;
 
 	ret = set_l3_qos_cfg(r_l3, true);
 	if (!ret) {
-		r_l3->enabled = false;
-		r_l3data->enabled = true;
-		r_l3code->enabled = true;
+		r_l3->alloc_enabled = false;
+		r_l3data->alloc_enabled = true;
+		r_l3code->alloc_enabled = true;
 	}
 	return ret;
 }
···
 {
 	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3];
 
-	r->enabled = r->capable;
+	r->alloc_enabled = r->alloc_capable;
 
-	if (rdt_resources_all[RDT_RESOURCE_L3DATA].enabled) {
-		rdt_resources_all[RDT_RESOURCE_L3DATA].enabled = false;
-		rdt_resources_all[RDT_RESOURCE_L3CODE].enabled = false;
+	if (rdt_resources_all[RDT_RESOURCE_L3DATA].alloc_enabled) {
+		rdt_resources_all[RDT_RESOURCE_L3DATA].alloc_enabled = false;
+		rdt_resources_all[RDT_RESOURCE_L3CODE].alloc_enabled = false;
 		set_l3_qos_cfg(r, false);
 	}
 }
···
 	}
 }
 
+static int mkdir_mondata_all(struct kernfs_node *parent_kn,
+			     struct rdtgroup *prgrp,
+			     struct kernfs_node **mon_data_kn);
+
 static struct dentry *rdt_mount(struct file_system_type *fs_type,
 				int flags, const char *unused_dev_name,
 				void *data)
 {
+	struct rdt_domain *dom;
+	struct rdt_resource *r;
 	struct dentry *dentry;
 	int ret;
 
···
 		goto out_cdp;
 	}
 
+	if (rdt_mon_capable) {
+		ret = mongroup_create_dir(rdtgroup_default.kn,
+					  NULL, "mon_groups",
+					  &kn_mongrp);
+		if (ret) {
+			dentry = ERR_PTR(ret);
+			goto out_info;
+		}
+		kernfs_get(kn_mongrp);
+
+		ret = mkdir_mondata_all(rdtgroup_default.kn,
+					&rdtgroup_default, &kn_mondata);
+		if (ret) {
+			dentry = ERR_PTR(ret);
+			goto out_mongrp;
+		}
+		kernfs_get(kn_mondata);
+		rdtgroup_default.mon.mon_data_kn = kn_mondata;
+	}
+
 	dentry = kernfs_mount(fs_type, flags, rdt_root,
 			      RDTGROUP_SUPER_MAGIC, NULL);
 	if (IS_ERR(dentry))
-		goto out_destroy;
+		goto out_mondata;
 
-	static_branch_enable(&rdt_enable_key);
+	if (rdt_alloc_capable)
+		static_branch_enable(&rdt_alloc_enable_key);
+	if (rdt_mon_capable)
+		static_branch_enable(&rdt_mon_enable_key);
+
+	if (rdt_alloc_capable || rdt_mon_capable)
+		static_branch_enable(&rdt_enable_key);
+
+	if (is_mbm_enabled()) {
+		r = &rdt_resources_all[RDT_RESOURCE_L3];
+		list_for_each_entry(dom, &r->domains, list)
+			mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL);
+	}
+
 	goto out;
 
-out_destroy:
+out_mondata:
+	if (rdt_mon_capable)
+		kernfs_remove(kn_mondata);
+out_mongrp:
+	if (rdt_mon_capable)
+		kernfs_remove(kn_mongrp);
+out_info:
 	kernfs_remove(kn_info);
 out_cdp:
 	cdp_disable();
···
 	return 0;
 }
 
+static bool is_closid_match(struct task_struct *t, struct rdtgroup *r)
+{
+	return (rdt_alloc_capable &&
+		(r->type == RDTCTRL_GROUP) && (t->closid == r->closid));
+}
+
+static bool is_rmid_match(struct task_struct *t, struct rdtgroup *r)
+{
+	return (rdt_mon_capable &&
+		(r->type == RDTMON_GROUP) && (t->rmid == r->mon.rmid));
+}
+
 /*
  * Move tasks from one to the other group. If @from is NULL, then all tasks
  * in the systems are moved unconditionally (used for teardown).
···
 
 	read_lock(&tasklist_lock);
 	for_each_process_thread(p, t) {
-		if (!from || t->closid == from->closid) {
+		if (!from || is_closid_match(t, from) ||
+		    is_rmid_match(t, from)) {
 			t->closid = to->closid;
+			t->rmid = to->mon.rmid;
+
 #ifdef CONFIG_SMP
 			/*
 			 * This is safe on x86 w/o barriers as the ordering
···
 	read_unlock(&tasklist_lock);
 }
 
+static void free_all_child_rdtgrp(struct rdtgroup *rdtgrp)
+{
+	struct rdtgroup *sentry, *stmp;
+	struct list_head *head;
+
+	head = &rdtgrp->mon.crdtgrp_list;
+	list_for_each_entry_safe(sentry, stmp, head, mon.crdtgrp_list) {
+		free_rmid(sentry->mon.rmid);
+		list_del(&sentry->mon.crdtgrp_list);
+		kfree(sentry);
+	}
+}
+
 /*
  * Forcibly remove all of subdirectories under root.
  */
···
 	rdt_move_group_tasks(NULL, &rdtgroup_default, NULL);
 
 	list_for_each_entry_safe(rdtgrp, tmp, &rdt_all_groups, rdtgroup_list) {
+		/* Free any child rmids */
+		free_all_child_rdtgrp(rdtgrp);
+
 		/* Remove each rdtgroup other than root */
 		if (rdtgrp == &rdtgroup_default)
 			continue;
···
 		cpumask_or(&rdtgroup_default.cpu_mask,
 			   &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
 
+		free_rmid(rdtgrp->mon.rmid);
+
 		kernfs_remove(rdtgrp->kn);
 		list_del(&rdtgrp->rdtgroup_list);
 		kfree(rdtgrp);
 	}
 	/* Notify online CPUs to update per cpu storage and PQR_ASSOC MSR */
 	get_online_cpus();
-	rdt_update_closid(cpu_online_mask, &rdtgroup_default.closid);
+	update_closid_rmid(cpu_online_mask, &rdtgroup_default);
 	put_online_cpus();
 
 	kernfs_remove(kn_info);
+	kernfs_remove(kn_mongrp);
+	kernfs_remove(kn_mondata);
 }
 
 static void rdt_kill_sb(struct super_block *sb)
···
 	mutex_lock(&rdtgroup_mutex);
 
 	/*Put everything back to default values. */
-	for_each_enabled_rdt_resource(r)
+	for_each_alloc_enabled_rdt_resource(r)
 		reset_all_ctrls(r);
 	cdp_disable();
 	rmdir_all_sub();
+	static_branch_disable(&rdt_alloc_enable_key);
+	static_branch_disable(&rdt_mon_enable_key);
 	static_branch_disable(&rdt_enable_key);
 	kernfs_kill_sb(sb);
 	mutex_unlock(&rdtgroup_mutex);
···
 	.kill_sb = rdt_kill_sb,
 };
 
-static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
-			  umode_t mode)
+static int mon_addfile(struct kernfs_node *parent_kn, const char *name,
+		       void *priv)
 {
-	struct rdtgroup *parent, *rdtgrp;
 	struct kernfs_node *kn;
-	int ret, closid;
+	int ret = 0;
 
-	/* Only allow mkdir in the root directory */
-	if (parent_kn != rdtgroup_default.kn)
-		return -EPERM;
+	kn = __kernfs_create_file(parent_kn, name, 0444, 0,
+				  &kf_mondata_ops, priv, NULL, NULL);
+	if (IS_ERR(kn))
+		return PTR_ERR(kn);
 
-	/* Do not accept '\n' to avoid unparsable situation. */
-	if (strchr(name, '\n'))
-		return -EINVAL;
+	ret = rdtgroup_kn_set_ugid(kn);
+	if (ret) {
+		kernfs_remove(kn);
+		return ret;
+	}
 
-	parent = rdtgroup_kn_lock_live(parent_kn);
-	if (!parent) {
+	return ret;
+}
+
+/*
+ * Remove all subdirectories of mon_data of ctrl_mon groups
+ * and monitor groups with given domain id.
+ */
+void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r, unsigned int dom_id)
+{
+	struct rdtgroup *prgrp, *crgrp;
+	char name[32];
+
+	if (!r->mon_enabled)
+		return;
+
+	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
+		sprintf(name, "mon_%s_%02d", r->name, dom_id);
+		kernfs_remove_by_name(prgrp->mon.mon_data_kn, name);
+
+		list_for_each_entry(crgrp, &prgrp->mon.crdtgrp_list, mon.crdtgrp_list)
+			kernfs_remove_by_name(crgrp->mon.mon_data_kn, name);
+	}
+}
+
+static int mkdir_mondata_subdir(struct kernfs_node *parent_kn,
+				struct rdt_domain *d,
+				struct rdt_resource *r, struct rdtgroup *prgrp)
+{
+	union mon_data_bits priv;
+	struct kernfs_node *kn;
+	struct mon_evt *mevt;
+	struct rmid_read rr;
+	char name[32];
+	int ret;
+
+	sprintf(name, "mon_%s_%02d", r->name, d->id);
+	/* create the directory */
+	kn = kernfs_create_dir(parent_kn, name, parent_kn->mode, prgrp);
+	if (IS_ERR(kn))
+		return PTR_ERR(kn);
+
+	/*
+	 * This extra ref will be put in kernfs_remove() and guarantees
+	 * that kn is always accessible.
+	 */
+	kernfs_get(kn);
+	ret = rdtgroup_kn_set_ugid(kn);
+	if (ret)
+		goto out_destroy;
+
+	if (WARN_ON(list_empty(&r->evt_list))) {
+		ret = -EPERM;
+		goto out_destroy;
+	}
+
+	priv.u.rid = r->rid;
+	priv.u.domid = d->id;
+	list_for_each_entry(mevt, &r->evt_list, list) {
+		priv.u.evtid = mevt->evtid;
+		ret = mon_addfile(kn, mevt->name, priv.priv);
+		if (ret)
+			goto out_destroy;
+
+		if (is_mbm_event(mevt->evtid))
+			mon_event_read(&rr, d, prgrp, mevt->evtid, true);
+	}
+	kernfs_activate(kn);
+	return 0;
+
+out_destroy:
+	kernfs_remove(kn);
+	return ret;
+}
+
+/*
+ * Add all subdirectories of mon_data for "ctrl_mon" groups
+ * and "monitor" groups with given domain id.
+ */
+void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
+				    struct rdt_domain *d)
+{
+	struct kernfs_node *parent_kn;
+	struct rdtgroup *prgrp, *crgrp;
+	struct list_head *head;
+
+	if (!r->mon_enabled)
+		return;
+
+	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
+		parent_kn = prgrp->mon.mon_data_kn;
+		mkdir_mondata_subdir(parent_kn, d, r, prgrp);
+
+		head = &prgrp->mon.crdtgrp_list;
+		list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
+			parent_kn = crgrp->mon.mon_data_kn;
+			mkdir_mondata_subdir(parent_kn, d, r, crgrp);
+		}
+	}
+}
+
+static int mkdir_mondata_subdir_alldom(struct kernfs_node *parent_kn,
+				       struct rdt_resource *r,
+				       struct rdtgroup *prgrp)
+{
+	struct rdt_domain *dom;
+	int ret;
+
+	list_for_each_entry(dom, &r->domains, list) {
+		ret = mkdir_mondata_subdir(parent_kn, dom, r, prgrp);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/*
+ * This creates a directory mon_data which contains the monitored data.
+ *
+ * mon_data has one directory for each domain whic are named
+ * in the format mon_<domain_name>_<domain_id>. For ex: A mon_data
+ * with L3 domain looks as below:
+ * ./mon_data:
+ * mon_L3_00
+ * mon_L3_01
+ * mon_L3_02
+ * ...
+ *
+ * Each domain directory has one file per event:
+ * ./mon_L3_00/:
+ * llc_occupancy
+ *
+ */
+static int mkdir_mondata_all(struct kernfs_node *parent_kn,
+			     struct rdtgroup *prgrp,
+			     struct kernfs_node **dest_kn)
+{
+	struct rdt_resource *r;
+	struct kernfs_node *kn;
+	int ret;
+
+	/*
+	 * Create the mon_data directory first.
+	 */
+	ret = mongroup_create_dir(parent_kn, NULL, "mon_data", &kn);
+	if (ret)
+		return ret;
+
+	if (dest_kn)
+		*dest_kn = kn;
+
+	/*
+	 * Create the subdirectories for each domain. Note that all events
+	 * in a domain like L3 are grouped into a resource whose domain is L3
+	 */
+	for_each_mon_enabled_rdt_resource(r) {
+		ret = mkdir_mondata_subdir_alldom(kn, r, prgrp);
+		if (ret)
+			goto out_destroy;
+	}
+
+	return 0;
+
+out_destroy:
+	kernfs_remove(kn);
+	return ret;
+}
+
+static int mkdir_rdt_prepare(struct kernfs_node *parent_kn,
+			     struct kernfs_node *prgrp_kn,
+			     const char *name, umode_t mode,
+			     enum rdt_group_type rtype, struct rdtgroup **r)
+{
+	struct rdtgroup *prdtgrp, *rdtgrp;
+	struct kernfs_node *kn;
+	uint files = 0;
+	int ret;
+
+	prdtgrp = rdtgroup_kn_lock_live(prgrp_kn);
+	if (!prdtgrp) {
 		ret = -ENODEV;
 		goto out_unlock;
 	}
-
-	ret = closid_alloc();
-	if (ret < 0)
-		goto out_unlock;
-	closid = ret;
 
 	/* allocate the rdtgroup. */
 	rdtgrp = kzalloc(sizeof(*rdtgrp), GFP_KERNEL);
 	if (!rdtgrp) {
 		ret = -ENOSPC;
-		goto out_closid_free;
+		goto out_unlock;
 	}
-	rdtgrp->closid = closid;
-	list_add(&rdtgrp->rdtgroup_list, &rdt_all_groups);
+	*r = rdtgrp;
+	rdtgrp->mon.parent = prdtgrp;
+	rdtgrp->type = rtype;
+	INIT_LIST_HEAD(&rdtgrp->mon.crdtgrp_list);
 
 	/* kernfs creates the directory for rdtgrp */
-	kn = kernfs_create_dir(parent->kn, name, mode, rdtgrp);
+	kn = kernfs_create_dir(parent_kn, name, mode, rdtgrp);
 	if (IS_ERR(kn)) {
 		ret = PTR_ERR(kn);
-		goto out_cancel_ref;
+		goto out_free_rgrp;
 	}
 	rdtgrp->kn = kn;
 
···
 	if (ret)
 		goto out_destroy;
 
-	ret = rdtgroup_add_files(kn, rdtgroup_base_files,
-				 ARRAY_SIZE(rdtgroup_base_files));
+	files = RFTYPE_BASE | RFTYPE_CTRL;
+	files = RFTYPE_BASE | BIT(RF_CTRLSHIFT + rtype);
+	ret = rdtgroup_add_files(kn, files);
 	if (ret)
 		goto out_destroy;
 
+	if (rdt_mon_capable) {
+		ret = alloc_rmid();
+		if (ret < 0)
+			goto out_destroy;
+		rdtgrp->mon.rmid = ret;
+
+		ret = mkdir_mondata_all(kn, rdtgrp, &rdtgrp->mon.mon_data_kn);
+		if (ret)
+			goto out_idfree;
+	}
 	kernfs_activate(kn);
 
-	ret = 0;
-	goto out_unlock;
+	/*
+	 * The caller unlocks the prgrp_kn upon success.
+	 */
+	return 0;
 
+out_idfree:
+	free_rmid(rdtgrp->mon.rmid);
 out_destroy:
 	kernfs_remove(rdtgrp->kn);
-out_cancel_ref:
-	list_del(&rdtgrp->rdtgroup_list);
+out_free_rgrp:
 	kfree(rdtgrp);
-out_closid_free:
-	closid_free(closid);
 out_unlock:
-	rdtgroup_kn_unlock(parent_kn);
+	rdtgroup_kn_unlock(prgrp_kn);
 	return ret;
+}
+
+static void mkdir_rdt_prepare_clean(struct rdtgroup *rgrp)
+{
+	kernfs_remove(rgrp->kn);
+	free_rmid(rgrp->mon.rmid);
+	kfree(rgrp);
+}
+
+/*
+ * Create a monitor group under "mon_groups" directory of a control
+ * and monitor group(ctrl_mon). This is a resource group
+ * to monitor a subset of tasks and cpus in its parent ctrl_mon group.
+ */
+static int rdtgroup_mkdir_mon(struct kernfs_node *parent_kn,
+			      struct kernfs_node *prgrp_kn,
+			      const char *name,
+			      umode_t mode)
+{
+	struct rdtgroup *rdtgrp, *prgrp;
+	int ret;
+
+	ret = mkdir_rdt_prepare(parent_kn, prgrp_kn, name, mode, RDTMON_GROUP,
+				&rdtgrp);
+	if (ret)
+		return ret;
+
+	prgrp = rdtgrp->mon.parent;
+	rdtgrp->closid = prgrp->closid;
+
+	/*
+	 * Add the rdtgrp to the list of rdtgrps the parent
+	 * ctrl_mon group has to track.
+	 */
+	list_add_tail(&rdtgrp->mon.crdtgrp_list, &prgrp->mon.crdtgrp_list);
+
+	rdtgroup_kn_unlock(prgrp_kn);
+	return ret;
+}
+
+/*
+ * These are rdtgroups created under the root directory. Can be used
+ * to allocate and monitor resources.
+ */
+static int rdtgroup_mkdir_ctrl_mon(struct kernfs_node *parent_kn,
+				   struct kernfs_node *prgrp_kn,
+				   const char *name, umode_t mode)
+{
+	struct rdtgroup *rdtgrp;
+	struct kernfs_node *kn;
+	u32 closid;
+	int ret;
+
+	ret = mkdir_rdt_prepare(parent_kn, prgrp_kn, name, mode, RDTCTRL_GROUP,
+				&rdtgrp);
+	if (ret)
+		return ret;
+
+	kn = rdtgrp->kn;
+	ret = closid_alloc();
+	if (ret < 0)
+		goto out_common_fail;
+	closid = ret;
+
+	rdtgrp->closid = closid;
+	list_add(&rdtgrp->rdtgroup_list, &rdt_all_groups);
+
+	if (rdt_mon_capable) {
+		/*
+		 * Create an empty mon_groups directory to hold the subset
+		 * of tasks and cpus to monitor.
+		 */
+		ret = mongroup_create_dir(kn, NULL, "mon_groups", NULL);
+		if (ret)
+			goto out_id_free;
+	}
+
+	goto out_unlock;
+
+out_id_free:
+	closid_free(closid);
+	list_del(&rdtgrp->rdtgroup_list);
+out_common_fail:
+	mkdir_rdt_prepare_clean(rdtgrp);
+out_unlock:
+	rdtgroup_kn_unlock(prgrp_kn);
+	return ret;
+}
+
+/*
+ * We allow creating mon groups only with in a directory called "mon_groups"
+ * which is present in every ctrl_mon group. Check if this is a valid
+ * "mon_groups" directory.
+ *
+ * 1. The directory should be named "mon_groups".
+ * 2. The mon group itself should "not" be named "mon_groups".
+ *   This makes sure "mon_groups" directory always has a ctrl_mon group
+ *   as parent.
+ */
+static bool is_mon_groups(struct kernfs_node *kn, const char *name)
+{
+	return (!strcmp(kn->name, "mon_groups") &&
+		strcmp(name, "mon_groups"));
+}
+
+static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
+			  umode_t mode)
+{
+	/* Do not accept '\n' to avoid unparsable situation. */
+	if (strchr(name, '\n'))
+		return -EINVAL;
+
+	/*
+	 * If the parent directory is the root directory and RDT
+	 * allocation is supported, add a control and monitoring
+	 * subdirectory
+	 */
+	if (rdt_alloc_capable && parent_kn == rdtgroup_default.kn)
+		return rdtgroup_mkdir_ctrl_mon(parent_kn, parent_kn, name, mode);
+
+	/*
+	 * If RDT monitoring is supported and the parent directory is a valid
+	 * "mon_groups" directory, add a monitoring subdirectory.
+	 */
+	if (rdt_mon_capable && is_mon_groups(parent_kn, name))
+		return rdtgroup_mkdir_mon(parent_kn, parent_kn->parent, name, mode);
+
+	return -EPERM;
+}
+
+static int rdtgroup_rmdir_mon(struct kernfs_node *kn, struct rdtgroup *rdtgrp,
+			      cpumask_var_t tmpmask)
+{
+	struct rdtgroup *prdtgrp = rdtgrp->mon.parent;
+	int cpu;
+
+	/* Give any tasks back to the parent group */
+	rdt_move_group_tasks(rdtgrp, prdtgrp, tmpmask);
+
+	/* Update per cpu rmid of the moved CPUs first */
+	for_each_cpu(cpu, &rdtgrp->cpu_mask)
+		per_cpu(pqr_state.default_rmid, cpu) = prdtgrp->mon.rmid;
+	/*
+	 * Update the MSR on moved CPUs and CPUs which have moved
+	 * task running on them.
+	 */
+	cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask);
+	update_closid_rmid(tmpmask, NULL);
+
+	rdtgrp->flags = RDT_DELETED;
+	free_rmid(rdtgrp->mon.rmid);
+
+	/*
+	 * Remove the rdtgrp from the parent ctrl_mon group's list
+	 */
+	WARN_ON(list_empty(&prdtgrp->mon.crdtgrp_list));
+	list_del(&rdtgrp->mon.crdtgrp_list);
+
+	/*
+	 * one extra hold on this, will drop when we kfree(rdtgrp)
+	 * in rdtgroup_kn_unlock()
+	 */
+	kernfs_get(kn);
+	kernfs_remove(rdtgrp->kn);
+
+	return 0;
+}
+
+static int rdtgroup_rmdir_ctrl(struct kernfs_node *kn, struct rdtgroup *rdtgrp,
+			       cpumask_var_t tmpmask)
+{
+	int cpu;
+
+	/* Give any tasks back to the default group */
+	rdt_move_group_tasks(rdtgrp, &rdtgroup_default, tmpmask);
+
+	/* Give any CPUs back to the default group */
+	cpumask_or(&rdtgroup_default.cpu_mask,
+		   &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
+
+	/* Update per cpu closid and rmid of the moved CPUs first */
+	for_each_cpu(cpu, &rdtgrp->cpu_mask) {
+		per_cpu(pqr_state.default_closid, cpu) = rdtgroup_default.closid;
+		per_cpu(pqr_state.default_rmid, cpu) = rdtgroup_default.mon.rmid;
+	}
+
+	/*
+	 * Update the MSR on moved CPUs and CPUs which have moved
+	 * task running on them.
+	 */
+	cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask);
+	update_closid_rmid(tmpmask, NULL);
+
+	rdtgrp->flags = RDT_DELETED;
+	closid_free(rdtgrp->closid);
+	free_rmid(rdtgrp->mon.rmid);
+
+	/*
+	 * Free all the child monitor group rmids.
+	 */
+	free_all_child_rdtgrp(rdtgrp);
+
+	list_del(&rdtgrp->rdtgroup_list);
+
+	/*
+	 * one extra hold on this, will drop when we kfree(rdtgrp)
+	 * in rdtgroup_kn_unlock()
+	 */
+	kernfs_get(kn);
+	kernfs_remove(rdtgrp->kn);
+
+	return 0;
 }
 
 static int rdtgroup_rmdir(struct kernfs_node *kn)
 {
-	int ret, cpu, closid = rdtgroup_default.closid;
+	struct kernfs_node *parent_kn = kn->parent;
 	struct rdtgroup *rdtgrp;
 	cpumask_var_t tmpmask;
+	int ret = 0;
 
 	if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL))
 		return -ENOMEM;
···
 		goto out;
 	}
 
-	/* Give any tasks back to the default group */
-	rdt_move_group_tasks(rdtgrp, &rdtgroup_default, tmpmask);
-
-	/* Give any CPUs back to the default group */
-	cpumask_or(&rdtgroup_default.cpu_mask,
-		   &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
-
-	/* Update per cpu closid of the moved CPUs first */
-	for_each_cpu(cpu, &rdtgrp->cpu_mask)
-		per_cpu(cpu_closid, cpu) = closid;
 	/*
-	 * Update the MSR on moved CPUs and CPUs which have moved
-	 * task running on them.
+	 * If the rdtgroup is a ctrl_mon group and parent directory
+	 * is the root directory, remove the ctrl_mon group.
+	 *
+	 * If the rdtgroup is a mon group and parent directory
+	 * is a valid "mon_groups" directory, remove the mon group.
 	 */
-	cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask);
-	rdt_update_closid(tmpmask, NULL);
+	if (rdtgrp->type == RDTCTRL_GROUP && parent_kn == rdtgroup_default.kn)
+		ret = rdtgroup_rmdir_ctrl(kn, rdtgrp, tmpmask);
+	else if (rdtgrp->type == RDTMON_GROUP &&
+		 is_mon_groups(parent_kn, kn->name))
+		ret = rdtgroup_rmdir_mon(kn, rdtgrp, tmpmask);
+	else
+		ret = -EPERM;
 
-	rdtgrp->flags = RDT_DELETED;
-	closid_free(rdtgrp->closid);
-	list_del(&rdtgrp->rdtgroup_list);
-
-	/*
-	 * one extra hold on this, will drop when we kfree(rdtgrp)
-	 * in rdtgroup_kn_unlock()
-	 */
-	kernfs_get(kn);
-	kernfs_remove(rdtgrp->kn);
-	ret = 0;
 out:
 	rdtgroup_kn_unlock(kn);
 	free_cpumask_var(tmpmask);
···
 
 static int rdtgroup_show_options(struct seq_file *seq, struct kernfs_root *kf)
 {
-	if (rdt_resources_all[RDT_RESOURCE_L3DATA].enabled)
+	if (rdt_resources_all[RDT_RESOURCE_L3DATA].alloc_enabled)
 		seq_puts(seq, ",cdp");
 	return 0;
 }
···
 	mutex_lock(&rdtgroup_mutex);
 
 	rdtgroup_default.closid = 0;
+	rdtgroup_default.mon.rmid = 0;
+	rdtgroup_default.type = RDTCTRL_GROUP;
+	INIT_LIST_HEAD(&rdtgroup_default.mon.crdtgrp_list);
+
 	list_add(&rdtgroup_default.rdtgroup_list, &rdt_all_groups);
 
-	ret = rdtgroup_add_files(rdt_root->kn, rdtgroup_base_files,
-				 ARRAY_SIZE(rdtgroup_base_files));
+	ret = rdtgroup_add_files(rdt_root->kn, RF_CTRL_BASE);
 	if (ret) {
 		kernfs_destroy_root(rdt_root);
 		goto out;

arch/x86/kernel/cpu/intel_rdt_schemata.c arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c

···
 #include <linux/kernfs.h>
 #include <linux/seq_file.h>
 #include <linux/slab.h>
-#include <asm/intel_rdt.h>
+#include "intel_rdt.h"
 
 /*
  * Check whether MBA bandwidth percentage value is correct. The value is
···
 {
 	struct rdt_resource *r;
 
-	for_each_enabled_rdt_resource(r) {
+	for_each_alloc_enabled_rdt_resource(r) {
 		if (!strcmp(resname, r->name) && closid < r->num_closid)
 			return parse_line(tok, r);
 	}
···
 
 	closid = rdtgrp->closid;
 
-	for_each_enabled_rdt_resource(r) {
+	for_each_alloc_enabled_rdt_resource(r) {
 		list_for_each_entry(dom, &r->domains, list)
 			dom->have_new_ctrl = false;
 	}
···
 			goto out;
 	}
 
-	for_each_enabled_rdt_resource(r) {
+	for_each_alloc_enabled_rdt_resource(r) {
 		ret = update_domains(r, closid);
 		if (ret)
 			goto out;
···
 {
 	struct rdtgroup *rdtgrp;
 	struct rdt_resource *r;
-	int closid, ret = 0;
+	int ret = 0;
+	u32 closid;
 
 	rdtgrp = rdtgroup_kn_lock_live(of->kn);
 	if (rdtgrp) {
 		closid = rdtgrp->closid;
-		for_each_enabled_rdt_resource(r) {
+		for_each_alloc_enabled_rdt_resource(r) {
 			if (closid < r->num_closid)
 				show_doms(s, r, closid);
 		}
 	} else {
 		ret = -ENOENT;
 	}
+	rdtgroup_kn_unlock(of->kn);
+	return ret;
+}
+
+void mon_event_read(struct rmid_read *rr, struct rdt_domain *d,
+		    struct rdtgroup *rdtgrp, int evtid, int first)
+{
+	/*
+	 * setup the parameters to send to the IPI to read the data.
+	 */
+	rr->rgrp = rdtgrp;
+	rr->evtid = evtid;
+	rr->d = d;
+	rr->val = 0;
+	rr->first = first;
+
+	smp_call_function_any(&d->cpu_mask, mon_event_count, rr, 1);
+}
+
+int rdtgroup_mondata_show(struct seq_file *m, void *arg)
+{
+	struct kernfs_open_file *of = m->private;
+	u32 resid, evtid, domid;
+	struct rdtgroup *rdtgrp;
+	struct rdt_resource *r;
+	union mon_data_bits md;
+	struct rdt_domain *d;
+	struct rmid_read rr;
+	int ret = 0;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+
+	md.priv = of->kn->priv;
+	resid = md.u.rid;
+	domid = md.u.domid;
+	evtid = md.u.evtid;
+
+	r = &rdt_resources_all[resid];
+	d = rdt_find_domain(r, domid, NULL);
+	if (!d) {
+		ret = -ENOENT;
+		goto out;
+	}
+
+	mon_event_read(&rr, d, rdtgrp, evtid, false);
+
+	if (rr.val & RMID_VAL_ERROR)
+		seq_puts(m, "Error\n");
+	else if (rr.val & RMID_VAL_UNAVAIL)
+		seq_puts(m, "Unavailable\n");
+	else
+		seq_printf(m, "%llu\n", rr.val * r->mon_scale);
+
+out:
 	rdtgroup_kn_unlock(of->kn);
 	return ret;
 }

arch/x86/kernel/process_32.c

···
 #include <asm/debugreg.h>
 #include <asm/switch_to.h>
 #include <asm/vm86.h>
-#include <asm/intel_rdt.h>
+#include <asm/intel_rdt_sched.h>
 #include <asm/proto.h>
 
 void __show_regs(struct pt_regs *regs, int all)

arch/x86/kernel/process_64.c

···
 #include <asm/switch_to.h>
 #include <asm/xen/hypervisor.h>
 #include <asm/vdso.h>
-#include <asm/intel_rdt.h>
+#include <asm/intel_rdt_sched.h>
 #include <asm/unistd.h>
 #ifdef CONFIG_IA32_EMULATION
 /* Not included via unistd.h */

include/linux/perf_event.h

···
 			/* for tp_event->class */
 			struct list_head	tp_list;
 		};
-		struct { /* intel_cqm */
-			int			cqm_state;
-			u32			cqm_rmid;
-			int			is_group_event;
-			struct list_head	cqm_events_entry;
-			struct list_head	cqm_groups_entry;
-			struct list_head	cqm_group_entry;
-		};
 		struct { /* amd_power */
 			u64	pwr_acc;
 			u64	ptsc;
···
 	 */
 	size_t				task_ctx_size;
 
-
-	/*
-	 * Return the count value for a counter.
-	 */
-	u64 (*count)			(struct perf_event *event); /*optional*/
 
 	/*
 	 * Set up pmu-private data structures for an AUX area
···
 
 	if (static_branch_unlikely(&perf_sched_events))
 		__perf_event_task_sched_out(prev, next);
-}
-
-static inline u64 __perf_event_count(struct perf_event *event)
-{
-	return local64_read(&event->count) + atomic64_read(&event->child_count);
 }
 
 extern void perf_event_mmap(struct vm_area_struct *vma);

include/linux/sched.h

···
 	/* cg_list protected by css_set_lock and tsk->alloc_lock: */
 	struct list_head		cg_list;
 #endif
-#ifdef CONFIG_INTEL_RDT_A
-	int				closid;
+#ifdef CONFIG_INTEL_RDT
+	u32				closid;
+	u32				rmid;
 #endif
 #ifdef CONFIG_FUTEX
 	struct robust_list_head __user	*robust_list;

kernel/events/core.c

···
 
 static inline u64 perf_event_count(struct perf_event *event)
 {
-	if (event->pmu->count)
-		return event->pmu->count(event);
-
-	return __perf_event_count(event);
+	return local64_read(&event->count) + atomic64_read(&event->child_count);
 }
 
 /*
···
 	 * all child counters from atomic context.
 	 */
 	if (event->attr.inherit) {
-		ret = -EOPNOTSUPP;
-		goto out;
-	}
-
-	/*
-	 * It must not have a pmu::count method, those are not
-	 * NMI safe.
-	 */
-	if (event->pmu->count) {
 		ret = -EOPNOTSUPP;
 		goto out;
 	}