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Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
Previously the part behind "perf-" was interpreted as an internal perf
command. If the suffix could not be handled, the execution was stopped.
This makes it impossible to launch perf binaries that got renamed to
have the `perf-` prefix. This is e.g. the case for appimages (e.g.
"perf-x86_64.AppImage"), but would also apply to all other scenarios
where users symlink or rename perf themselves:
Status quo with the broken behavior:
$ ln -s ./perf ./perf-custom-suffix
$ ./perf-custom-suffix list
cannot handle custom-suffix internally$
Also note the missing newline at the end of the error message.
With this patch applied, the above works properly:
$ ./perf-custom-suffix list
List of pre-defined events (to be used in -e):
...
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Acked-by: David Ahern <dsahern@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20170911111422.31903-1-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently section->from_system_config is being checked multiple times.
item->from_system_config should be checked instead, when iterating thru
the items in a section. Fix it.
Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1504754325-9724-1-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We currently update the 'next' variable only with a single step value.
But it's possible the 'adv' update is bigger than single 'step' value.
This would leave 'next' value under counted and force unnecessary
ui_progress__ops->update calls.
Calculate the amount of steps we need for 'adv' update and increase the
'next' with that amounts of steps.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170908120510.22515-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Unlikely, but we could have ui_progress__init being called with total <
16, which would set the next and step variables to 0. That would force
unnecessary ui_progress__ops->update calls because 'next' would never
raise.
Forcing the next and step values to be always > 0.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170908120510.22515-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Do not carry the perf.data file descriptor into the workload process and
close it when perf executes the workload.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170908084621.31595-2-jolsa@kernel.org
[ Add definitions for O_CLOEXEC for older systems ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Do not use -D_FORTIFY_SOURCE=2 for DEBUG build as it seems to mess up
with debuginfo, which results in bad gdb experience.
We already do that for tools/perf/.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170908084621.31595-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When cross compiling perf and I want to link against a self-compiled
libunwind, I usually make the custom path where the libunwind headers
exist visible by adding the libunwind prefix to the include path when
compiling perf, i.e.:
~~~~~
$ ls $HOME/projects/compiled/other/include/
libunwind-coredump.h libunwind.h libunwind-x86_64.h
libunwind-common.h libunwind-dynamic.h libunwind-ptrace.h
unwind.h
$ make EXTRA_CFLAGS="-I$HOME/projects/compiled/other/include/
~~~~~~
Note the `unwind.h` header from libunwind which leads to compile
errors when compiling tests/dwarf-unwind.c, since it shadows perf's
util/unwind.h:
~~~~~
tests/dwarf-unwind.c:41:32: error: ‘struct unwind_entry’ declared inside parameter list will not be visible outside of this definition or declaration [-Werror]
static int unwind_entry(struct unwind_entry *entry, void *arg)
^~~~~~~~~~~~
tests/dwarf-unwind.c: In function ‘unwind_entry’:
tests/dwarf-unwind.c:44:22: error: dereferencing pointer to incomplete type ‘struct unwind_entry’
char *symbol = entry->sym ? entry->sym->name : NULL;
^~
tests/dwarf-unwind.c: In function ‘unwind_thread’:
tests/dwarf-unwind.c:92:8: error: implicit declaration of function ‘unwind__get_entries’; did you mean ‘unwind_entry’? [-Werror=implicit-function-declaration]
err = unwind__get_entries(unwind_entry, &cnt, thread,
^~~~~~~~~~~~~~~~~~~
unwind_entry
tests/dwarf-unwind.c:92:8: error: nested extern declaration of ‘unwind__get_entries’ [-Werror=nested-externs]
~~~~~~
Fix this compile error by specificing an explicit include of perf's
unwind.h in the util folder.
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20170906150209.12579-1-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When cross building to android r15c (and older versions) on Fedora 26
we notice these:
/opt/android-ndk-r15c/platforms/android-24/arch-arm/usr/include/sys/cdefs.h:332:0: note: this is the location of the previous definition
For __aligned, __packed and __noreturn, so guard those with ifdefs to
avoid drowning useful warnings in these.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-d7w3fa9c22dtmrwbedos6ie1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
- Support syscall name glob matching in 'perf trace' (Arnaldo Carvalho de Melo)
e.g.:
# perf trace -e pkey_*
32.784 (0.006 ms): pkey/16018 pkey_alloc(init_val: DISABLE_WRITE) = -1 EINVAL Invalid argument
32.795 (0.004 ms): pkey/16018 pkey_mprotect(start: 0x7f380d0a6000, len: 4096, prot: READ|WRITE, pkey: -1) = 0
32.801 (0.002 ms): pkey/16018 pkey_free(pkey: -1 ) = -1 EINVAL Invalid argument
^C#
- Do not auto merge counts for explicitely specified events in
'perf stat' (Arnaldo Carvalho de Melo)
- Fix syntax in documentation of .perfconfig intel-pt option (Jack Henschel)
- Calculate the average cycles of iterations for loops detected by the
branch history support in 'perf report' (Jin Yao)
- Support PERF_SAMPLE_PHYS_ADDR as a sort key "phys_daddr" in the 'script', 'mem',
'top' and 'report'. Also add a test entry for it in 'perf test' (Kan Liang)
- Fix 'Object code reading' 'perf test' entry in PowerPC (Ravi Bangoria)
- Remove some duplicate Power9 duplicate vendor events (described in JSON
files) (Sukadev Bhattiprolu)
- Add help entry in the TUI annotate browser about cycling thru hottest
instructions with TAB/shift+TAB (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 apic updates from Thomas Gleixner:
"This update provides:
- Cleanup of the IDT management including the removal of the extra
tracing IDT. A first step to cleanup the vector management code.
- The removal of the paravirt op adjust_exception_frame. This is a
XEN specific issue, but merged through this branch to avoid nasty
merge collisions
- Prevent dmesg spam about the TSC DEADLINE bug, when the CPU has
disabled the TSC DEADLINE timer in CPUID.
- Adjust a debug message in the ioapic code to print out the
information correctly"
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
x86/idt: Fix the X86_TRAP_BP gate
x86/xen: Get rid of paravirt op adjust_exception_frame
x86/eisa: Add missing include
x86/idt: Remove superfluous ALIGNment
x86/apic: Silence "FW_BUG TSC_DEADLINE disabled due to Errata" on CPUs without the feature
x86/idt: Remove the tracing IDT leftovers
x86/idt: Hide set_intr_gate()
x86/idt: Simplify alloc_intr_gate()
x86/idt: Deinline setup functions
x86/idt: Remove unused functions/inlines
x86/idt: Move interrupt gate initialization to IDT code
x86/idt: Move APIC gate initialization to tables
x86/idt: Move regular trap init to tables
x86/idt: Move IST stack based traps to table init
x86/idt: Move debug stack init to table based
x86/idt: Switch early trap init to IDT tables
x86/idt: Prepare for table based init
x86/idt: Move early IDT setup out of 32-bit asm
x86/idt: Move early IDT handler setup to IDT code
x86/idt: Consolidate IDT invalidation
...
The popup help accessed via 'h' wasn't mentioning about TAB and
shift-TAB, just about 'H', which goes to the hottest line, while the
former two are the hotkeys for actually cycling thru the hottest lines.
Reported-by: Flavio Bruno Leitner <fbl@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-5ppym6odizfj1ifa4t7neiku@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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
...
Andrei Vagin reported a CRIU regression and bisected it back to:
90f6225fba0c ("x86/idt: Move IST stack based traps to table init")
This table init conversion loses the system-gate property of X86_TRAP_BP
and erroneously moves it from DPL3 to DPL0.
Fix it.
Reported-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: dvlasenk@redhat.com
Cc: linux-tip-commits@vger.kernel.org
Cc: peterz@infradead.org
Cc: brgerst@gmail.com
Cc: rostedt@goodmis.org
Cc: bp@alien8.de
Cc: luto@kernel.org
Cc: jpoimboe@redhat.com
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: torvalds@linux-foundation.org
Cc: tip-bot for Jacob Shin <tipbot@zytor.com>
Link: http://lkml.kernel.org/r/20170901082630.xvyi5bwk6etmppqc@gmail.com
Peter reported that when he explicitely asked for multiple events with
the same name on the command line it got coalesced into just one line,
i.e.:
# perf stat -e cycles -e cycles -e cycles usleep 1
Performance counter stats for 'usleep 1':
3,269,652 cycles
0.000884123 seconds time elapsed
#
And while there is the --no-merges option to disable that auto-merging,
this is a blunt change in behaviour for such explicit request, so change
the code so that this auto merging is done only when handling the multi
PMU aliases with the same name that introduced this coalescing,
restoring the previous behaviour for the explicit case:
# perf stat -e cycles -e cycles -e cycles usleep 1
Performance counter stats for 'usleep 1':
1,472,837 cycles
1,472,837 cycles
1,472,837 cycles
0.001764870 seconds time elapsed
#
Reported-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 430daf2dc7af ("perf stat: Collapse identically named events")
Link: http://lkml.kernel.org/r/20170831184122.GK4831@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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