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authorLinus Torvalds <torvalds@linux-foundation.org>2016-03-18 19:26:54 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-03-18 19:26:54 -0700
commit814a2bf957739f367cbebfa1b60237387b72d0ee (patch)
tree8d65c38d14beb8d6d2dc5b9d7f8dbe63c7cad31a /Documentation
parent237045fc3c67d44088f767dca5a9fa30815eba62 (diff)
parentf9310b2f9a19b7f16c7b1c1558f8b649b9b933c1 (diff)
downloadlinux-814a2bf957739f367cbebfa1b60237387b72d0ee.tar.bz2
Merge branch 'akpm' (patches from Andrew)
Merge second patch-bomb from Andrew Morton: - a couple of hotfixes - the rest of MM - a new timer slack control in procfs - a couple of procfs fixes - a few misc things - some printk tweaks - lib/ updates, notably to radix-tree. - add my and Nick Piggin's old userspace radix-tree test harness to tools/testing/radix-tree/. Matthew said it was a godsend during the radix-tree work he did. - a few code-size improvements, switching to __always_inline where gcc screwed up. - partially implement character sets in sscanf * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits) sscanf: implement basic character sets lib/bug.c: use common WARN helper param: convert some "on"/"off" users to strtobool lib: add "on"/"off" support to kstrtobool lib: update single-char callers of strtobool() lib: move strtobool() to kstrtobool() include/linux/unaligned: force inlining of byteswap operations include/uapi/linux/byteorder, swab: force inlining of some byteswap operations include/asm-generic/atomic-long.h: force inlining of some atomic_long operations usb: common: convert to use match_string() helper ide: hpt366: convert to use match_string() helper ata: hpt366: convert to use match_string() helper power: ab8500: convert to use match_string() helper power: charger_manager: convert to use match_string() helper drm/edid: convert to use match_string() helper pinctrl: convert to use match_string() helper device property: convert to use match_string() helper lib/string: introduce match_string() helper radix-tree tests: add test for radix_tree_iter_next radix-tree tests: add regression3 test ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/cgroup-v1/cgroups.txt2
-rw-r--r--Documentation/cgroup-v1/cpusets.txt2
-rw-r--r--Documentation/cgroup-v2.txt25
-rw-r--r--Documentation/filesystems/proc.txt18
-rw-r--r--Documentation/sysctl/vm.txt18
-rw-r--r--Documentation/vm/transhuge.txt22
6 files changed, 85 insertions, 2 deletions
diff --git a/Documentation/cgroup-v1/cgroups.txt b/Documentation/cgroup-v1/cgroups.txt
index c6256ae9885b..947e6fe31ef9 100644
--- a/Documentation/cgroup-v1/cgroups.txt
+++ b/Documentation/cgroup-v1/cgroups.txt
@@ -8,7 +8,7 @@ Original copyright statements from cpusets.txt:
Portions Copyright (C) 2004 BULL SA.
Portions Copyright (c) 2004-2006 Silicon Graphics, Inc.
Modified by Paul Jackson <pj@sgi.com>
-Modified by Christoph Lameter <clameter@sgi.com>
+Modified by Christoph Lameter <cl@linux.com>
CONTENTS:
=========
diff --git a/Documentation/cgroup-v1/cpusets.txt b/Documentation/cgroup-v1/cpusets.txt
index fdf7dff3f607..e5cdcd445615 100644
--- a/Documentation/cgroup-v1/cpusets.txt
+++ b/Documentation/cgroup-v1/cpusets.txt
@@ -6,7 +6,7 @@ Written by Simon.Derr@bull.net
Portions Copyright (c) 2004-2006 Silicon Graphics, Inc.
Modified by Paul Jackson <pj@sgi.com>
-Modified by Christoph Lameter <clameter@sgi.com>
+Modified by Christoph Lameter <cl@linux.com>
Modified by Paul Menage <menage@google.com>
Modified by Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
diff --git a/Documentation/cgroup-v2.txt b/Documentation/cgroup-v2.txt
index ff49cf901148..8f1329a5f700 100644
--- a/Documentation/cgroup-v2.txt
+++ b/Documentation/cgroup-v2.txt
@@ -843,6 +843,15 @@ PAGE_SIZE multiple when read back.
Amount of memory used to cache filesystem data,
including tmpfs and shared memory.
+ kernel_stack
+
+ Amount of memory allocated to kernel stacks.
+
+ slab
+
+ Amount of memory used for storing in-kernel data
+ structures.
+
sock
Amount of memory used in network transmission buffers
@@ -871,6 +880,16 @@ PAGE_SIZE multiple when read back.
on the internal memory management lists used by the
page reclaim algorithm
+ slab_reclaimable
+
+ Part of "slab" that might be reclaimed, such as
+ dentries and inodes.
+
+ slab_unreclaimable
+
+ Part of "slab" that cannot be reclaimed on memory
+ pressure.
+
pgfault
Total number of page faults incurred
@@ -1368,6 +1387,12 @@ system than killing the group. Otherwise, memory.max is there to
limit this type of spillover and ultimately contain buggy or even
malicious applications.
+Setting the original memory.limit_in_bytes below the current usage was
+subject to a race condition, where concurrent charges could cause the
+limit setting to fail. memory.max on the other hand will first set the
+limit to prevent new charges, and then reclaim and OOM kill until the
+new limit is met - or the task writing to memory.max is killed.
+
The combined memory+swap accounting and limiting is replaced by real
control over swap space.
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 843b045b4069..7f5607a089b4 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -43,6 +43,7 @@ Table of Contents
3.7 /proc/<pid>/task/<tid>/children - Information about task children
3.8 /proc/<pid>/fdinfo/<fd> - Information about opened file
3.9 /proc/<pid>/map_files - Information about memory mapped files
+ 3.10 /proc/<pid>/timerslack_ns - Task timerslack value
4 Configuring procfs
4.1 Mount options
@@ -1862,6 +1863,23 @@ time one can open(2) mappings from the listings of two processes and
comparing their inode numbers to figure out which anonymous memory areas
are actually shared.
+3.10 /proc/<pid>/timerslack_ns - Task timerslack value
+---------------------------------------------------------
+This file provides the value of the task's timerslack value in nanoseconds.
+This value specifies a amount of time that normal timers may be deferred
+in order to coalesce timers and avoid unnecessary wakeups.
+
+This allows a task's interactivity vs power consumption trade off to be
+adjusted.
+
+Writing 0 to the file will set the tasks timerslack to the default value.
+
+Valid values are from 0 - ULLONG_MAX
+
+An application setting the value must have PTRACE_MODE_ATTACH_FSCREDS level
+permissions on the task specified to change its timerslack_ns value.
+
+
------------------------------------------------------------------------------
Configuring procfs
------------------------------------------------------------------------------
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index 89a887c76629..cb0368459da3 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -803,6 +803,24 @@ performance impact. Reclaim code needs to take various locks to find freeable
directory and inode objects. With vfs_cache_pressure=1000, it will look for
ten times more freeable objects than there are.
+=============================================================
+
+watermark_scale_factor:
+
+This factor controls the aggressiveness of kswapd. It defines the
+amount of memory left in a node/system before kswapd is woken up and
+how much memory needs to be free before kswapd goes back to sleep.
+
+The unit is in fractions of 10,000. The default value of 10 means the
+distances between watermarks are 0.1% of the available memory in the
+node/system. The maximum value is 1000, or 10% of memory.
+
+A high rate of threads entering direct reclaim (allocstall) or kswapd
+going to sleep prematurely (kswapd_low_wmark_hit_quickly) can indicate
+that the number of free pages kswapd maintains for latency reasons is
+too small for the allocation bursts occurring in the system. This knob
+can then be used to tune kswapd aggressiveness accordingly.
+
==============================================================
zone_reclaim_mode:
diff --git a/Documentation/vm/transhuge.txt b/Documentation/vm/transhuge.txt
index 21cf34f3ddb2..d9cb65cf5cfd 100644
--- a/Documentation/vm/transhuge.txt
+++ b/Documentation/vm/transhuge.txt
@@ -113,9 +113,26 @@ guaranteed, but it may be more likely in case the allocation is for a
MADV_HUGEPAGE region.
echo always >/sys/kernel/mm/transparent_hugepage/defrag
+echo defer >/sys/kernel/mm/transparent_hugepage/defrag
echo madvise >/sys/kernel/mm/transparent_hugepage/defrag
echo never >/sys/kernel/mm/transparent_hugepage/defrag
+"always" means that an application requesting THP will stall on allocation
+failure and directly reclaim pages and compact memory in an effort to
+allocate a THP immediately. This may be desirable for virtual machines
+that benefit heavily from THP use and are willing to delay the VM start
+to utilise them.
+
+"defer" means that an application will wake kswapd in the background
+to reclaim pages and wake kcompact to compact memory so that THP is
+available in the near future. It's the responsibility of khugepaged
+to then install the THP pages later.
+
+"madvise" will enter direct reclaim like "always" but only for regions
+that are have used madvise(MADV_HUGEPAGE). This is the default behaviour.
+
+"never" should be self-explanatory.
+
By default kernel tries to use huge zero page on read page fault.
It's possible to disable huge zero page by writing 0 or enable it
back by writing 1:
@@ -229,6 +246,11 @@ thp_split_page is incremented every time a huge page is split into base
thp_split_page_failed is is incremented if kernel fails to split huge
page. This can happen if the page was pinned by somebody.
+thp_deferred_split_page is incremented when a huge page is put onto split
+ queue. This happens when a huge page is partially unmapped and
+ splitting it would free up some memory. Pages on split queue are
+ going to be split under memory pressure.
+
thp_split_pmd is incremented every time a PMD split into table of PTEs.
This can happen, for instance, when application calls mprotect() or
munmap() on part of huge page. It doesn't split huge page, only