Commit 61b5d771 authored Apr 28, 2022 by Joel Savitz Committed by Greg Kroah-Hartman Aug 30, 2023

Documentation/sysctl: document page_lock_unfairness

commit 8d98e42fb20c25e8efdab4cc1ac46d52ba964aca upstream.

commit 5ef64cc8987a ("mm: allow a controlled amount of unfairness in the
page lock") introduced a new systctl but no accompanying documentation.

Add a simple entry to the documentation.

Link: https://lkml.kernel.org/r/20220325164437.120246-1-jsavitz@redhat.com


Signed-off-by: Joel Savitz <jsavitz@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: "zhangyi (F)" <yi.zhang@huawei.com>
Cc: Charan Teja Reddy <charante@codeaurora.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent b2421a19

Documentation/admin-guide/sysctl/vm.rst

+9 −0

Original line number	Diff line number	Diff line
		@@ -61,6 +61,7 @@ Currently, these files are in /proc/sys/vm:
		- overcommit_memory
		- overcommit_ratio
		- page-cluster
		- page_lock_unfairness
		- panic_on_oom
		- percpu_pagelist_fraction
		- stat_interval
		@@ -741,6 +742,14 @@ extra faults and I/O delays for following faults if they would have been part of
		that consecutive pages readahead would have brought in.


		page_lock_unfairness
		====================

		This value determines the number of times that the page lock can be
		stolen from under a waiter. After the lock is stolen the number of times
		specified in this file (default is 5), the "fair lock handoff" semantics
		will apply, and the waiter will only be awakened if the lock can be taken.

		panic_on_oom
		============