xref: /openbmc/linux/fs/proc/Kconfig (revision 32daa5d7)
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 CRASH_CORE
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 	default n
96 	help
97 	  Provides a fast way to retrieve first level children pids of a task. See
98 	  <file:Documentation/filesystems/proc.rst> for more information.
99 
100 	  Say Y if you are running any user-space software which takes benefit from
101 	  this interface. For example, rkt is such a piece of software.
102 
103 config PROC_PID_ARCH_STATUS
104 	def_bool n
105 	depends on PROC_FS
106 
107 config PROC_CPU_RESCTRL
108 	def_bool n
109 	depends on PROC_FS
110