Commit a05a70db authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'akpm' (patches from Andrew) 

Merge updates from Andrew Morton:

 - fsnotify fix

 - poll() timeout fix

 - a few scripts/ tweaks

 - debugobjects updates

 - the (small) ocfs2 queue

 - Minor fixes to kernel/padata.c

 - Maybe half of the MM queue

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (117 commits)
  mm, page_alloc: restore the original nodemask if the fast path allocation failed
  mm, page_alloc: uninline the bad page part of check_new_page()
  mm, page_alloc: don't duplicate code in free_pcp_prepare
  mm, page_alloc: defer debugging checks of pages allocated from the PCP
  mm, page_alloc: defer debugging checks of freed pages until a PCP drain
  cpuset: use static key better and convert to new API
  mm, page_alloc: inline pageblock lookup in page free fast paths
  mm, page_alloc: remove unnecessary variable from free_pcppages_bulk
  mm, page_alloc: pull out side effects from free_pages_check
  mm, page_alloc: un-inline the bad part of free_pages_check
  mm, page_alloc: check multiple page fields with a single branch
  mm, page_alloc: remove field from alloc_context
  mm, page_alloc: avoid looking up the first zone in a zonelist twice
  mm, page_alloc: shortcut watermark checks for order-0 pages
  mm, page_alloc: reduce cost of fair zone allocation policy retry
  mm, page_alloc: shorten the page allocator fast path
  mm, page_alloc: check once if a zone has isolated pageblocks
  mm, page_alloc: move __GFP_HARDWALL modifications out of the fastpath
  mm, page_alloc: simplify last cpupid reset
  mm, page_alloc: remove unnecessary initialisation from __alloc_pages_nodemask()
  ...
parents 03b979dd 4741526b

Documentation/DocBook/debugobjects.tmpl

+14 −12
Original line number Diff line number Diff line
@@ -316,8 +316,8 @@ 
	</itemizedlist>

      </para>

      <para>

	The function returns 1 when the fixup was successful,

	otherwise 0. The return value is used to update the

	The function returns true when the fixup was successful,

	otherwise false. The return value is used to update the

	statistics.

      </para>

      <para>
@@ -341,8 +341,8 @@ 
	</itemizedlist>

      </para>

      <para>

	The function returns 1 when the fixup was successful,

	otherwise 0. The return value is used to update the

	The function returns true when the fixup was successful,

	otherwise false. The return value is used to update the

	statistics.

      </para>

      <para>
@@ -359,7 +359,8 @@ 
	statically initialized object or not. In case it is it calls

	debug_object_init() and debug_object_activate() to make the

	object known to the tracker and marked active. In this case

	the function should return 0 because this is not a real fixup.

	the function should return false because this is not a real

	fixup.

      </para>

    </sect1>
@@ -376,8 +377,8 @@ 
	</itemizedlist>

      </para>

      <para>

	The function returns 1 when the fixup was successful,

	otherwise 0. The return value is used to update the

	The function returns true when the fixup was successful,

	otherwise false. The return value is used to update the

	statistics.

      </para>

    </sect1>
@@ -397,8 +398,8 @@ 
	</itemizedlist>

      </para>

      <para>

	The function returns 1 when the fixup was successful,

	otherwise 0. The return value is used to update the

	The function returns true when the fixup was successful,

	otherwise false. The return value is used to update the

	statistics.

      </para>

    </sect1>
@@ -414,8 +415,8 @@ 
	debug bucket.

      </para>

      <para>

	The function returns 1 when the fixup was successful,

	otherwise 0. The return value is used to update the

	The function returns true when the fixup was successful,

	otherwise false. The return value is used to update the

	statistics.

      </para>

      <para>
@@ -427,7 +428,8 @@ 
	case. The fixup function should check if this is a legitimate

	case of a statically initialized object or not. In this case only

	debug_object_init() should be called to make the object known to

	the tracker. Then the function should return 0 because this is not

	the tracker. Then the function should return false because this

	is not

	a real fixup.

      </para>

    </sect1>

Documentation/kernel-parameters.txt

+8 −0
Original line number Diff line number Diff line
@@ -2168,6 +2168,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted. 
			[KNL,SH] Allow user to override the default size for

			per-device physically contiguous DMA buffers.



        memhp_default_state=online/offline

			[KNL] Set the initial state for the memory hotplug

			onlining policy. If not specified, the default value is

			set according to the

			CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE kernel config

			option.

			See Documentation/memory-hotplug.txt.



	memmap=exactmap	[KNL,X86] Enable setting of an exact

			E820 memory map, as specified by the user.

			Such memmap=exactmap lines can be constructed based on

Documentation/memory-hotplug.txt

+5 −4
Original line number Diff line number Diff line
@@ -261,10 +261,11 @@ it according to the policy which can be read from "auto_online_blocks" file: 


% cat /sys/devices/system/memory/auto_online_blocks



The default is "offline" which means the newly added memory is not in a

ready-to-use state and you have to "online" the newly added memory blocks

manually. Automatic onlining can be requested by writing "online" to

"auto_online_blocks" file:

The default depends on the CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE kernel config

option. If it is disabled the default is "offline" which means the newly added

memory is not in a ready-to-use state and you have to "online" the newly added

memory blocks manually. Automatic onlining can be requested by writing "online"

to "auto_online_blocks" file:



% echo online > /sys/devices/system/memory/auto_online_blocks

Documentation/sysctl/vm.txt

+14 −0
Original line number Diff line number Diff line
@@ -57,6 +57,7 @@ Currently, these files are in /proc/sys/vm: 
- panic_on_oom

- percpu_pagelist_fraction

- stat_interval

- stat_refresh

- swappiness

- user_reserve_kbytes

- vfs_cache_pressure
@@ -755,6 +756,19 @@ is 1 second. 


==============================================================



stat_refresh



Any read or write (by root only) flushes all the per-cpu vm statistics

into their global totals, for more accurate reports when testing

e.g. cat /proc/sys/vm/stat_refresh /proc/meminfo



As a side-effect, it also checks for negative totals (elsewhere reported

as 0) and "fails" with EINVAL if any are found, with a warning in dmesg.

(At time of writing, a few stats are known sometimes to be found negative,

with no ill effects: errors and warnings on these stats are suppressed.)



==============================================================



swappiness



This control is used to define how aggressive the kernel will swap

Documentation/vm/transhuge.txt

+5 −5
Original line number Diff line number Diff line
@@ -394,9 +394,9 @@ hugepage natively. Once finished you can drop the page table lock. 
Refcounting on THP is mostly consistent with refcounting on other compound

pages:



  - get_page()/put_page() and GUP operate in head page's ->_count.

  - get_page()/put_page() and GUP operate in head page's ->_refcount.



  - ->_count in tail pages is always zero: get_page_unless_zero() never

  - ->_refcount in tail pages is always zero: get_page_unless_zero() never

    succeed on tail pages.



  - map/unmap of the pages with PTE entry increment/decrement ->_mapcount
@@ -426,15 +426,15 @@ requests to split pinned huge page: it expects page count to be equal to 
sum of mapcount of all sub-pages plus one (split_huge_page caller must

have reference for head page).



split_huge_page uses migration entries to stabilize page->_count and

split_huge_page uses migration entries to stabilize page->_refcount and

page->_mapcount.



We safe against physical memory scanners too: the only legitimate way

scanner can get reference to a page is get_page_unless_zero().



All tail pages has zero ->_count until atomic_add(). It prevent scanner

All tail pages has zero ->_refcount until atomic_add(). It prevent scanner

from geting reference to tail page up to the point. After the atomic_add()

we don't care about ->_count value.  We already known how many references

we don't care about ->_refcount value.  We already known how many references

with should uncharge from head page.



For head page get_page_unless_zero() will succeed and we don't mind. It's

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