linux-toradex.git/include/linux/slab.h, branch v3.14.3

mm: fix GFP_THISNODE callers and clarify

2014-03-11T00:26:19+00:00

GFP_THISNODE is for callers that implement their own clever fallback to
remote nodes.  It restricts the allocation to the specified node and
does not invoke reclaim, assuming that the caller will take care of it
when the fallback fails, e.g.  through a subsequent allocation request
without GFP_THISNODE set.

However, many current GFP_THISNODE users only want the node exclusive
aspect of the flag, without actually implementing their own fallback or
triggering reclaim if necessary.  This results in things like page
migration failing prematurely even when there is easily reclaimable
memory available, unless kswapd happens to be running already or a
concurrent allocation attempt triggers the necessary reclaim.

Convert all callsites that don't implement their own fallback strategy
to __GFP_THISNODE.  This restricts the allocation a single node too, but
at the same time allows the allocator to enter the slowpath, wake
kswapd, and invoke direct reclaim if necessary, to make the allocation
happen when memory is full.

Signed-off-by: Johannes Weiner 
Acked-by: Rik van Riel 
Cc: Jan Stancek 
Cc: Mel Gorman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux

2014-02-02T19:30:08+00:00

Pull SLAB changes from Pekka Enberg:
 "Random bug fixes that have accumulated in my inbox over the past few
  months"

* 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux:
  mm: Fix warning on make htmldocs caused by slab.c
  mm: slub: work around unneeded lockdep warning
  mm: sl[uo]b: fix misleading comments
  slub: Fix possible format string bug.
  slub: use lockdep_assert_held
  slub: Fix calculation of cpu slabs
  slab.h: remove duplicate kmalloc declaration and fix kernel-doc warnings

mm: sl[uo]b: fix misleading comments

2014-01-31T11:40:34+00:00

On x86, SLUB creates and handles <=8192-byte allocations internally.
It passes larger ones up to the allocator.  Saying "up to order 2" is,
at best, ambiguous.  Is that order-1?  Or (order-2 bytes)?  Make
it more clear.

SLOB commits a similar sin.  It *handles* page-size requests, but the
comment says that it passes up "all page size and larger requests".

SLOB also swaps around the order of the very-similarly-named
KMALLOC_SHIFT_HIGH and KMALLOC_SHIFT_MAX #defines.  Make it
consistent with the order of the other two allocators.

Cc: Matt Mackall 
Cc: Andrew Morton 
Acked-by: Christoph Lameter 
Acked-by: David Rientjes 
Signed-off-by: Dave Hansen 
Signed-off-by: Pekka Enberg

memcg, slab: RCU protect memcg_params for root caches

2014-01-24T00:36:51+00:00

We relocate root cache's memcg_params whenever we need to grow the
memcg_caches array to accommodate all kmem-active memory cgroups.
Currently on relocation we free the old version immediately, which can
lead to use-after-free, because the memcg_caches array is accessed
lock-free (see cache_from_memcg_idx()).  This patch fixes this by making
memcg_params RCU-protected for root caches.

Signed-off-by: Vladimir Davydov 
Cc: Michal Hocko 
Cc: Glauber Costa 
Cc: Johannes Weiner 
Cc: Balbir Singh 
Cc: KAMEZAWA Hiroyuki 
Cc: Pekka Enberg 
Cc: Christoph Lameter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

slab.h: remove duplicate kmalloc declaration and fix kernel-doc warnings

2013-12-18T08:57:19+00:00

Fix kernel-doc warning for duplicate definition of 'kmalloc':

Documentation/DocBook/kernel-api.xml:9483: element refentry: validity error : ID API-kmalloc already defined


Also combine the kernel-doc info from the 2 kmalloc definitions into one
block and remove the "see kcalloc" comment since kmalloc now contains the
@flags info.

Signed-off-by: Randy Dunlap 
Acked-by: Christoph Lameter 
Signed-off-by: Pekka Enberg

slab.h: remove duplicate kmalloc declaration and fix kernel-doc warnings

2013-11-24T19:01:16+00:00

Fix kernel-doc warning for duplicate definition of 'kmalloc':

  Documentation/DocBook/kernel-api.xml:9483: element refentry: validity error : ID API-kmalloc already defined
  

Also combine the kernel-doc info from the 2 kmalloc definitions into one
block and remove the "see kcalloc" comment since kmalloc now contains the
@flags info.

Signed-off-by: Randy Dunlap 
Acked-by: Christoph Lameter 
Signed-off-by: Linus Torvalds

Merge branch 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux

2013-11-22T16:10:34+00:00

Pull SLAB changes from Pekka Enberg:
 "The patches from Joonsoo Kim switch mm/slab.c to use 'struct page' for
  slab internals similar to mm/slub.c.  This reduces memory usage and
  improves performance:

    https://lkml.org/lkml/2013/10/16/155

  Rest of the changes are bug fixes from various people"

* 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux: (21 commits)
  mm, slub: fix the typo in mm/slub.c
  mm, slub: fix the typo in include/linux/slub_def.h
  slub: Handle NULL parameter in kmem_cache_flags
  slab: replace non-existing 'struct freelist *' with 'void *'
  slab: fix to calm down kmemleak warning
  slub: proper kmemleak tracking if CONFIG_SLUB_DEBUG disabled
  slab: rename slab_bufctl to slab_freelist
  slab: remove useless statement for checking pfmemalloc
  slab: use struct page for slab management
  slab: replace free and inuse in struct slab with newly introduced active
  slab: remove SLAB_LIMIT
  slab: remove kmem_bufctl_t
  slab: change the management method of free objects of the slab
  slab: use __GFP_COMP flag for allocating slab pages
  slab: use well-defined macro, virt_to_slab()
  slab: overloading the RCU head over the LRU for RCU free
  slab: remove cachep in struct slab_rcu
  slab: remove nodeid in struct slab
  slab: remove colouroff in struct slab
  slab: change return type of kmem_getpages() to struct page
  ...

slab: overloading the RCU head over the LRU for RCU free

2013-10-24T17:17:31+00:00

With build-time size checking, we can overload the RCU head over the LRU
of struct page to free pages of a slab in rcu context. This really help to
implement to overload the struct slab over the struct page and this
eventually reduce memory usage and cache footprint of the SLAB.

Acked-by: Andi Kleen 
Acked-by: Christoph Lameter 
Signed-off-by: Joonsoo Kim 
Signed-off-by: Pekka Enberg

slab: Use correct GFP_DMA constant

2013-09-04T20:11:42+00:00

On Thu, 5 Sep 2013, kbuild test robot wrote:
> >> include/linux/slab.h:433:53: sparse: restricted gfp_t degrades to integer
>    429	static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
>    430	{
>    431	#ifndef CONFIG_SLOB
>    432		if (__builtin_constant_p(size) &&
>  > 433			size <= KMALLOC_MAX_CACHE_SIZE && !(flags & SLAB_CACHE_DMA)) {
>    434			int i = kmalloc_index(size);
>    435

flags is of type gfp_t and not a slab internal flag. Therefore
use GFP_DMA.

Signed-off-by: Christoph Lameter 
Signed-off-by: Pekka Enberg

mm/sl[aou]b: Move kmallocXXX functions to common code

2013-09-04T17:51:33+00:00

The kmalloc* functions of all slab allcoators are similar now so
lets move them into slab.h. This requires some function naming changes
in slob.

As a results of this patch there is a common set of functions for
all allocators. Also means that kmalloc_large() is now available
in general to perform large order allocations that go directly
via the page allocator. kmalloc_large() can be substituted if
kmalloc() throws warnings because of too large allocations.

kmalloc_large() has exactly the same semantics as kmalloc but
can only used for allocations > PAGE_SIZE.

Signed-off-by: Christoph Lameter 
Signed-off-by: Pekka Enberg