1 # SPDX-License-Identifier: GPL-2.0-only
2 config 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
32 config 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
41 config 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
48 config 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
64 config PROC_SYSCTL
65 bool "Sysctl support (/proc/sys)" if EXPERT
66 depends on PROC_FS
67 select SYSCTL
68 default y
69 help
70 The sysctl interface provides a means of dynamically changing
71 certain kernel parameters and variables on the fly without requiring
72 a recompile of the kernel or reboot of the system. The primary
73 interface is through /proc/sys. If you say Y here a tree of
74 modifiable sysctl entries will be generated beneath the
75 /proc/sys directory. They are explained in the files
76 in <file:Documentation/admin-guide/sysctl/>. Note that enabling this
77 option will enlarge the kernel by at least 8 KB.
78
79 As it is generally a good thing, you should say Y here unless
80 building a kernel for install/rescue disks or your system is very
81 limited in memory.
82
83 config PROC_PAGE_MONITOR
84 default y
85 depends on PROC_FS && MMU
86 bool "Enable /proc page monitoring" if EXPERT
87 help
88 Various /proc files exist to monitor process memory utilization:
89 /proc/pid/smaps, /proc/pid/clear_refs, /proc/pid/pagemap,
90 /proc/kpagecount, and /proc/kpageflags. Disabling these
91 interfaces will reduce the size of the kernel by approximately 4kb.
92
93 config PROC_CHILDREN
94 bool "Include /proc/<pid>/task/<tid>/children file"
95 depends on PROC_FS
96 default n
97 help
98 Provides a fast way to retrieve first level children pids of a task. See
99 <file:Documentation/filesystems/proc.rst> for more information.
100
101 Say Y if you are running any user-space software which takes benefit from
102 this interface. For example, rkt is such a piece of software.
103
104 config PROC_PID_ARCH_STATUS
105 def_bool n
106 depends on PROC_FS
107
108 config PROC_CPU_RESCTRL
109 def_bool n
110 depends on PROC_FS
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.