0001 # SPDX-License-Identifier: GPL-2.0-only
0002 config PROC_FS
0003 bool "/proc file system support" if EXPERT
0004 default y
0005 help
0006 This is a virtual file system providing information about the status
0007 of the system. "Virtual" means that it doesn't take up any space on
0008 your hard disk: the files are created on the fly by the kernel when
0009 you try to access them. Also, you cannot read the files with older
0010 version of the program less: you need to use more or cat.
0011
0012 It's totally cool; for example, "cat /proc/interrupts" gives
0013 information about what the different IRQs are used for at the moment
0014 (there is a small number of Interrupt ReQuest lines in your computer
0015 that are used by the attached devices to gain the CPU's attention --
0016 often a source of trouble if two devices are mistakenly configured
0017 to use the same IRQ). The program procinfo to display some
0018 information about your system gathered from the /proc file system.
0019
0020 Before you can use the /proc file system, it has to be mounted,
0021 meaning it has to be given a location in the directory hierarchy.
0022 That location should be /proc. A command such as "mount -t proc proc
0023 /proc" or the equivalent line in /etc/fstab does the job.
0024
0025 The /proc file system is explained in the file
0026 <file:Documentation/filesystems/proc.rst> and on the proc(5) manpage
0027 ("man 5 proc").
0028
0029 This option will enlarge your kernel by about 67 KB. Several
0030 programs depend on this, so everyone should say Y here.
0031
0032 config PROC_KCORE
0033 bool "/proc/kcore support" if !ARM
0034 depends on PROC_FS && MMU
0035 select CRASH_CORE
0036 help
0037 Provides a virtual ELF core file of the live kernel. This can
0038 be read with gdb and other ELF tools. No modifications can be
0039 made using this mechanism.
0040
0041 config PROC_VMCORE
0042 bool "/proc/vmcore support"
0043 depends on PROC_FS && CRASH_DUMP
0044 default y
0045 help
0046 Exports the dump image of crashed kernel in ELF format.
0047
0048 config PROC_VMCORE_DEVICE_DUMP
0049 bool "Device Hardware/Firmware Log Collection"
0050 depends on PROC_VMCORE
0051 default n
0052 help
0053 After kernel panic, device drivers can collect the device
0054 specific snapshot of their hardware or firmware before the
0055 underlying devices are initialized in crash recovery kernel.
0056 Note that the device driver must be present in the crash
0057 recovery kernel's initramfs to collect its underlying device
0058 snapshot.
0059
0060 If you say Y here, the collected device dumps will be added
0061 as ELF notes to /proc/vmcore. You can still disable device
0062 dump using the kernel command line option 'novmcoredd'.
0063
0064 config PROC_SYSCTL
0065 bool "Sysctl support (/proc/sys)" if EXPERT
0066 depends on PROC_FS
0067 select SYSCTL
0068 default y
0069 help
0070 The sysctl interface provides a means of dynamically changing
0071 certain kernel parameters and variables on the fly without requiring
0072 a recompile of the kernel or reboot of the system. The primary
0073 interface is through /proc/sys. If you say Y here a tree of
0074 modifiable sysctl entries will be generated beneath the
0075 /proc/sys directory. They are explained in the files
0076 in <file:Documentation/admin-guide/sysctl/>. Note that enabling this
0077 option will enlarge the kernel by at least 8 KB.
0078
0079 As it is generally a good thing, you should say Y here unless
0080 building a kernel for install/rescue disks or your system is very
0081 limited in memory.
0082
0083 config PROC_PAGE_MONITOR
0084 default y
0085 depends on PROC_FS && MMU
0086 bool "Enable /proc page monitoring" if EXPERT
0087 help
0088 Various /proc files exist to monitor process memory utilization:
0089 /proc/pid/smaps, /proc/pid/clear_refs, /proc/pid/pagemap,
0090 /proc/kpagecount, and /proc/kpageflags. Disabling these
0091 interfaces will reduce the size of the kernel by approximately 4kb.
0092
0093 config PROC_CHILDREN
0094 bool "Include /proc/<pid>/task/<tid>/children file"
0095 default n
0096 help
0097 Provides a fast way to retrieve first level children pids of a task. See
0098 <file:Documentation/filesystems/proc.rst> for more information.
0099
0100 Say Y if you are running any user-space software which takes benefit from
0101 this interface. For example, rkt is such a piece of software.
0102
0103 config PROC_PID_ARCH_STATUS
0104 def_bool n
0105 depends on PROC_FS
0106
0107 config PROC_CPU_RESCTRL
0108 def_bool n
0109 depends on PROC_FS
