Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1# SPDX-License-Identifier: GPL-2.0-only
2config PROC_FS
3 bool "/proc file system support" if EXPERT
4 default y
5 help
6 This is a virtual file system providing information about the status
7 of the system. "Virtual" means that it doesn't take up any space on
8 your hard disk: the files are created on the fly by the kernel when
9 you try to access them. Also, you cannot read the files with older
10 version of the program less: you need to use more or cat.
11
12 It's totally cool; for example, "cat /proc/interrupts" gives
13 information about what the different IRQs are used for at the moment
14 (there is a small number of Interrupt ReQuest lines in your computer
15 that are used by the attached devices to gain the CPU's attention --
16 often a source of trouble if two devices are mistakenly configured
17 to use the same IRQ). The program procinfo to display some
18 information about your system gathered from the /proc file system.
19
20 Before you can use the /proc file system, it has to be mounted,
21 meaning it has to be given a location in the directory hierarchy.
22 That location should be /proc. A command such as "mount -t proc proc
23 /proc" or the equivalent line in /etc/fstab does the job.
24
25 The /proc file system is explained in the file
26 <file:Documentation/filesystems/proc.rst> and on the proc(5) manpage
27 ("man 5 proc").
28
29 This option will enlarge your kernel by about 67 KB. Several
30 programs depend on this, so everyone should say Y here.
31
32config PROC_KCORE
33 bool "/proc/kcore support" if !ARM
34 depends on PROC_FS && MMU
35 select VMCORE_INFO
36 help
37 Provides a virtual ELF core file of the live kernel. This can
38 be read with gdb and other ELF tools. No modifications can be
39 made using this mechanism.
40
41config PROC_VMCORE
42 bool "/proc/vmcore support"
43 depends on PROC_FS && CRASH_DUMP
44 default y
45 help
46 Exports the dump image of crashed kernel in ELF format.
47
48config PROC_VMCORE_DEVICE_DUMP
49 bool "Device Hardware/Firmware Log Collection"
50 depends on PROC_VMCORE
51 default n
52 help
53 After kernel panic, device drivers can collect the device
54 specific snapshot of their hardware or firmware before the
55 underlying devices are initialized in crash recovery kernel.
56 Note that the device driver must be present in the crash
57 recovery kernel's initramfs to collect its underlying device
58 snapshot.
59
60 If you say Y here, the collected device dumps will be added
61 as ELF notes to /proc/vmcore. You can still disable device
62 dump using the kernel command line option 'novmcoredd'.
63
64config NEED_PROC_VMCORE_DEVICE_RAM
65 bool
66
67config PROC_VMCORE_DEVICE_RAM
68 def_bool y
69 depends on PROC_VMCORE && NEED_PROC_VMCORE_DEVICE_RAM
70 depends on VIRTIO_MEM
71 help
72 If the elfcore hdr is allocated and prepared by the dump kernel
73 ("2nd kernel") instead of the crashed kernel, RAM provided by memory
74 devices such as virtio-mem will not be included in the dump
75 image, because only the device driver can properly detect them.
76
77 With this config enabled, these RAM ranges will be queried from the
78 device drivers once the device gets probed, so they can be included
79 in the crash dump.
80
81 Relevant architectures should select NEED_PROC_VMCORE_DEVICE_RAM.
82
83config PROC_SYSCTL
84 bool "Sysctl support (/proc/sys)" if EXPERT
85 depends on PROC_FS
86 select SYSCTL
87 default y
88 help
89 The sysctl interface provides a means of dynamically changing
90 certain kernel parameters and variables on the fly without requiring
91 a recompile of the kernel or reboot of the system. The primary
92 interface is through /proc/sys. If you say Y here a tree of
93 modifiable sysctl entries will be generated beneath the
94 /proc/sys directory. They are explained in the files
95 in <file:Documentation/admin-guide/sysctl/>. Note that enabling this
96 option will enlarge the kernel by at least 8 KB.
97
98 As it is generally a good thing, you should say Y here unless
99 building a kernel for install/rescue disks or your system is very
100 limited in memory.
101
102config PROC_PAGE_MONITOR
103 default y
104 depends on PROC_FS && MMU
105 bool "Enable /proc page monitoring" if EXPERT
106 help
107 Various /proc files exist to monitor process memory utilization:
108 /proc/pid/smaps, /proc/pid/clear_refs, /proc/pid/pagemap,
109 /proc/kpagecount, and /proc/kpageflags. Disabling these
110 interfaces will reduce the size of the kernel by approximately 4kb.
111
112config PROC_CHILDREN
113 bool "Include /proc/<pid>/task/<tid>/children file"
114 depends on PROC_FS
115 default n
116 help
117 Provides a fast way to retrieve first level children pids of a task. See
118 <file:Documentation/filesystems/proc.rst> for more information.
119
120 Say Y if you are running any user-space software which takes benefit from
121 this interface. For example, rkt is such a piece of software.
122
123config PROC_PID_ARCH_STATUS
124 def_bool n
125 depends on PROC_FS
126
127config PROC_CPU_RESCTRL
128 def_bool n
129 depends on PROC_FS