Commit 8d98e42f authored by Joel Savitz's avatar Joel Savitz Committed by Andrew Morton
Browse files

Documentation/sysctl: document page_lock_unfairness

commit 5ef64cc8 ("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: default avatarJoel 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: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 4fcdcc12
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+9 −0
Original line number Diff line number Diff line
@@ -62,6 +62,7 @@ Currently, these files are in /proc/sys/vm:
- overcommit_memory
- overcommit_ratio
- page-cluster
- page_lock_unfairness
- panic_on_oom
- percpu_pagelist_high_fraction
- stat_interval
@@ -754,6 +755,14 @@ 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
============