The function names page_xchg_last_nid(), page_last_nid() and
reset_page_last_nid() were judged to be inconsistent so rename them to a
struct_field_op style pattern.  As it looked jarring to have
reset_page_mapcount() and page_nid_reset_last() beside each other in
memmap_init_zone(), this patch also renames reset_page_mapcount() to
page_mapcount_reset().  There are others like init_page_count() but as
it is used throughout the arch code a rename would likely cause more
conflicts than it is worth.

[akpm@linux-foundation.org: fix zcache]
Signed-off-by: NMel Gorman <mgorman@suse.de>
Suggested-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

struct page already has this information.  If we start chaining caches,
this information will always be more trustworthy than whatever is passed
into the function.
Signed-off-by: NGlauber Costa <glommer@parallels.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Frederic Weisbecker <fweisbec@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: JoonSoo Kim <js1304@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Rik van Riel <riel@redhat.com>
Cc: Suleiman Souhlal <suleiman@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Extract the code to do object alignment from the allocators.
Do the alignment calculations in slab_common so that the
__kmem_cache_create functions of the allocators do not have
to deal with alignment.
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

The definition of ARCH_SLAB_MINALIGN is architecture dependent
and can be either of type size_t or int. Comparing that value
with ARCH_KMALLOC_MINALIGN can cause harmless warnings on
platforms where they are different. Since both are always
small positive integer numbers, using the size_t type to compare
them is safe and gets rid of the warning.

Without this patch, building ARM collie_defconfig results in:

mm/slob.c: In function '__kmalloc_node':
mm/slob.c:431:152: warning: comparison of distinct pointer types lacks a cast [enabled by default]
mm/slob.c: In function 'kfree':
mm/slob.c:484:153: warning: comparison of distinct pointer types lacks a cast [enabled by default]
mm/slob.c: In function 'ksize':
mm/slob.c:503:153: warning: comparison of distinct pointer types lacks a cast [enabled by default]
Acked-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
[ penberg@kernel.org: updates for master ]
Signed-off-by: NPekka Enberg <penberg@kernel.org>

When freeing objects, the slob allocator currently free empty pages
calling __free_pages(). However, page-size kmallocs are disposed
using put_page() instead.

It makes no sense to call put_page() for kernel pages that are provided
by the object allocator, so we shouldn't be doing this ourselves.

This is based on:
commit d9b7f226
Author: Glauber Costa <glommer@parallels.com>
slub: use free_page instead of put_page for freeing kmalloc allocation

Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Matt Mackall <mpm@selenic.com>
Acked-by: NGlauber Costa <glommer@parallels.com>
Signed-off-by: NEzequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

This function is identically defined in all three allocators
and it's trivial to move it to slab.h

Since now it's static, inline, header-defined function
this patch also drops the EXPORT_SYMBOL tag.

Cc: Pekka Enberg <penberg@kernel.org>
Cc: Matt Mackall <mpm@selenic.com>
Acked-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NEzequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Fields object_size and size are not the same: the latter might include
slab metadata. Return object_size field in kmem_cache_size().
Also, improve trace accuracy by correctly tracing reported size.

Cc: Pekka Enberg <penberg@kernel.org>
Cc: Matt Mackall <mpm@selenic.com>
Acked-by: NChristoph Lameter <cl@linux.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NEzequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

This field was being used to store size allocation so it could be
retrieved by ksize(). However, it is a bad practice to not mark a page
as a slab page and then use fields for special purposes.
There is no need to store the allocated size and
ksize() can simply return PAGE_SIZE << compound_order(page).

Cc: Pekka Enberg <penberg@kernel.org>
Cc: Matt Mackall <mpm@selenic.com>
Acked-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NEzequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

The definition of ARCH_SLAB_MINALIGN is architecture dependent
and can be either of type size_t or int. Comparing that value
with ARCH_KMALLOC_MINALIGN can cause harmless warnings on
platforms where they are different. Since both are always
small positive integer numbers, using the size_t type to compare
them is safe and gets rid of the warning.

Without this patch, building ARM collie_defconfig results in:

mm/slob.c: In function '__kmalloc_node':
mm/slob.c:431:152: warning: comparison of distinct pointer types lacks a cast [enabled by default]
mm/slob.c: In function 'kfree':
mm/slob.c:484:153: warning: comparison of distinct pointer types lacks a cast [enabled by default]
mm/slob.c: In function 'ksize':
mm/slob.c:503:153: warning: comparison of distinct pointer types lacks a cast [enabled by default]
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NChristoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>

On Sat, 8 Sep 2012, Ezequiel Garcia wrote:

> @@ -454,15 +455,35 @@ void *__kmalloc_node(size_t size, gfp_t gfp, int node)
>  			gfp |= __GFP_COMP;
>  		ret = slob_new_pages(gfp, order, node);
>
> -		trace_kmalloc_node(_RET_IP_, ret,
> +		trace_kmalloc_node(caller, ret,
>  				   size, PAGE_SIZE << order, gfp, node);
>  	}
>
>  	kmemleak_alloc(ret, size, 1, gfp);
>  	return ret;
>  }
> +
> +void *__kmalloc_node(size_t size, gfp_t gfp, int node)
> +{
> +	return __do_kmalloc_node(size, gfp, node, _RET_IP_);
> +}
>  EXPORT_SYMBOL(__kmalloc_node);
>
> +#ifdef CONFIG_TRACING
> +void *__kmalloc_track_caller(size_t size, gfp_t gfp, unsigned long caller)
> +{
> +	return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, caller);
> +}
> +
> +#ifdef CONFIG_NUMA
> +void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
> +					int node, unsigned long caller)
> +{
> +	return __do_kmalloc_node(size, gfp, node, caller);
> +}
> +#endif

This breaks Pekka's slab/next tree with this:

mm/slob.c: In function '__kmalloc_node_track_caller':
mm/slob.c:488: error: 'gfp' undeclared (first use in this function)
mm/slob.c:488: error: (Each undeclared identifier is reported only once
mm/slob.c:488: error: for each function it appears in.)

mm, slob: fix build breakage in __kmalloc_node_track_caller

"mm, slob: Add support for kmalloc_track_caller()" breaks the build
because gfp is undeclared.  Fix it.
Acked-by: NEzequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Currently slob falls back to regular kmalloc for this case.
With this patch kmalloc_track_caller() is correctly implemented,
thus tracing the specified caller.

This is important to trace accurately allocations performed by
krealloc, kstrdup, kmemdup, etc.
Signed-off-by: NEzequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NEzequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Get rid of the refcount stuff in the allocators and do that part of
kmem_cache management in the common code.
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Do the initial settings of the fields in common code. This will allow us
to push more processing into common code later and improve readability.
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Shift the allocations to common code. That way the allocation and
freeing of the kmem_cache structures is handled by common code.
Reviewed-by: NGlauber Costa <glommer@parallels.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

What is done there can be done in __kmem_cache_shutdown.

This affects RCU handling somewhat. On rcu free all slab allocators do
not refer to other management structures than the kmem_cache structure.
Therefore these other structures can be freed before the rcu deferred
free to the page allocator occurs.
Reviewed-by: NJoonsoo Kim <js1304@gmail.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

The freeing action is basically the same in all slab allocators.
Move to the common kmem_cache_destroy() function.
Reviewed-by: NGlauber Costa <glommer@parallels.com>
Reviewed-by: NJoonsoo Kim <js1304@gmail.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Make all allocators use the "kmem_cache" slabname for the "kmem_cache"
structure.
Reviewed-by: NGlauber Costa <glommer@parallels.com>
Reviewed-by: NJoonsoo Kim <js1304@gmail.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

kmem_cache_destroy does basically the same in all allocators.

Extract common code which is easy since we already have common mutex
handling.
Reviewed-by: NGlauber Costa <glommer@parallels.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Move the code to append the new kmem_cache to the list of slab caches to
the kmem_cache_create code in the shared code.

This is possible now since the acquisition of the mutex was moved into
kmem_cache_create().
Acked-by: NDavid Rientjes <rientjes@google.com>
Reviewed-by: NGlauber Costa <glommer@parallels.com>
Reviewed-by: NJoonsoo Kim <js1304@gmail.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Commit fd3142a59af2012a7c5dc72ec97a4935ff1c5fc6 broke
slob since a piece of a change for a later patch slipped into
it.

Fengguang Wu writes:

  The commit crashes the kernel w/o any dmesg output (the attached one is
  created by the script as a summary for that run). This is very
  reproducible in kvm for the attached config.
Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

All allocators have some sort of support for the bootstrap status.

Setup a common definition for the boot states and make all slab
allocators use that definition.
Reviewed-by: NGlauber Costa <glommer@parallels.com>
Reviewed-by: NJoonsoo Kim <js1304@gmail.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Kmem_cache_create() does a variety of sanity checks but those
vary depending on the allocator. Use the strictest tests and put them into
a slab_common file. Make the tests conditional on CONFIG_DEBUG_VM.

This patch has the effect of adding sanity checks for SLUB and SLOB
under CONFIG_DEBUG_VM and removes the checks in SLAB for !CONFIG_DEBUG_VM.
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Define a struct that describes common fields used in all slab allocators.
A slab allocator either uses the common definition (like SLOB) or is
required to provide members of kmem_cache with the definition given.

After that it will be possible to share code that
only operates on those fields of kmem_cache.

The patch basically takes the slob definition of kmem cache and
uses the field namees for the other allocators.

It also standardizes the names used for basic object lengths in
allocators:

object_size	Struct size specified at kmem_cache_create. Basically
		the payload expected to be used by the subsystem.

size		The size of memory allocator for each object. This size
		is larger than object_size and includes padding, alignment
		and extra metadata for each object (f.e. for debugging
		and rcu).
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Those have become so simple that they are no longer needed.
Reviewed-by: NJoonsoo Kim <js1304@gmail.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Reviewed-by: NJoonsoo Kim <js1304@gmail.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

Define the fields used by slob in mm_types.h and use struct page instead
of struct slob_page in slob. This cleans up numerous of typecasts in slob.c and
makes readers aware of slob's use of page struct fields.

[Also cleans up some bitrot in slob.c. The page struct field layout
in slob.c is an old layout and does not match the one in mm_types.h]
Reviewed-by: NGlauber Costa <glommer@parallels.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Reviewed-by: NJoonsoo Kim <js1304@gmail.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

The files changed within are only using the EXPORT_SYMBOL
macro variants.  They are not using core modular infrastructure
and hence don't need module.h but only the export.h header.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: NArun Sharma <asharma@fb.com>
Reviewed-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Doing a ktest.pl randconfig, I stumbled across the following bug
on boot up:

------------[ cut here ]------------
WARNING: at /home/rostedt/work/autotest/nobackup/linux-test.git/kernel/lockdep.c:2649 lockdep_trace_alloc+0xed/0x100()
Hardware name:
Modules linked in:
Pid: 0, comm: swapper Not tainted 3.0.0-rc1-test-00054-g1d68b67 #1
Call Trace:
 [<ffffffff810626ad>] warn_slowpath_common+0xad/0xf0
 [<ffffffff8106270a>] warn_slowpath_null+0x1a/0x20
 [<ffffffff810b537d>] lockdep_trace_alloc+0xed/0x100
 [<ffffffff81182fb0>] __kmalloc_node+0x30/0x2f0
 [<ffffffff81153eda>] pcpu_mem_alloc+0x13a/0x180
 [<ffffffff82be022c>] percpu_init_late+0x48/0xc2
 [<ffffffff82bd630c>] ? mem_init+0xd8/0xe3
 [<ffffffff82bbcc73>] start_kernel+0x1c2/0x449
 [<ffffffff82bbc35c>] x86_64_start_reservations+0x163/0x167
 [<ffffffff82bbc493>] x86_64_start_kernel+0x133/0x142^M
---[ end trace a7919e7f17c0a725 ]---

Then I ran a ktest.pl config_bisect and it came up with this config
as the problem:

  CONFIG_SLOB

Looking at what is different between SLOB and SLAB and SLUB, I found
that the gfp flags are masked against gfp_allowed_mask in
SLAB and SLUB, but not SLOB.

On boot up, interrupts are disabled and lockdep will warn if some flags
are set in gfp and interrupts are disabled. But these flags are masked
off with the gfp_allowed_mask during boot. Because SLOB does not
mask the flags against gfp_allowed_mask it triggers the warn on.

Adding this mask fixes the bug. I also found that kmem_cache_alloc_node()
was missing both the mask and the lockdep check, and that was added too.
Acked-by: NMatt Mackall <mpm@selenic.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

The last user was ext4 and Eric Sandeen removed the call in a recent patch. See
the following URL for the discussion:

http://marc.info/?l=linux-ext4&m=129546975702198&w=2Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

This is a nasty and error prone API. It is no longer used, remove it.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

kmalloc_node() may allocate higher order slob pages, but the __GFP_COMP
bit is only passed to the page allocator and not represented in the
tracepoint event.  The bit should be passed to trace_kmalloc_node() as
well.
Acked-by: NMatt Mackall <mpm@selenic.com>
Reviewed-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NPekka Enberg <penberg@kernel.org>

SLOB has alloced smaller objects from their own list in reduce overall external
fragmentation and increase repeatability, free to their own list also.

This is /proc/meminfo result in my test machine:

  without this patch:
  ===
  MemTotal:        1030720 kB
  MemFree:          750012 kB
  Buffers:           15496 kB
  Cached:           160396 kB
  SwapCached:            0 kB
  Active:           105024 kB
  Inactive:         145604 kB
  Active(anon):      74816 kB
  Inactive(anon):     2180 kB
  Active(file):      30208 kB
  Inactive(file):   143424 kB
  Unevictable:          16 kB
  ....

  with this patch:
  ===
  MemTotal:        1030720 kB
  MemFree:          751908 kB
  Buffers:           15492 kB
  Cached:           160280 kB
  SwapCached:            0 kB
  Active:           102720 kB
  Inactive:         146140 kB
  Active(anon):      73168 kB
  Inactive(anon):     2180 kB
  Active(file):      29552 kB
  Inactive(file):   143960 kB
  Unevictable:          16 kB
  ...

The result shows an improvement of 1 MB!

And when I tested it on a embeded system with 64 MB, I found this path is never
called during kernel bootup.
Acked-by: NMatt Mackall <mpm@selenic.com>
Signed-off-by: NBob Liu <lliubbo@gmail.com>
Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>

Remove all rcu head inits. We don't care about the RCU head state before passing
it to call_rcu() anyway. Only leave the "on_stack" variants so debugobjects can
keep track of objects on stack.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Andrew Morton <akpm@linux-foundation.org>

We have been resisting new ftrace plugins and removing existing
ones, and kmemtrace has been superseded by kmem trace events
and perf-kmem, so we remove it.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NPekka Enberg <penberg@cs.helsinki.fi>
Acked-by: NEduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
[ remove kmemtrace from the makefile, handle slob too ]
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>

Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>

kmem_cache_init_late() has been declared in slab.h

CC: Nick Piggin <npiggin@suse.de>
CC: Matt Mackall <mpm@selenic.com>
CC: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>
Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>

Jesper noted that kmem_cache_destroy() invokes synchronize_rcu() rather than
rcu_barrier() in the SLAB_DESTROY_BY_RCU case, which could result in RCU
callbacks accessing a kmem_cache after it had been destroyed.

Cc: <stable@kernel.org>
Acked-by: NMatt Mackall <mpm@selenic.com>
Reported-by: NJesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>

Callers of alloc_pages_node() can optionally specify -1 as a node to mean
"allocate from the current node".  However, a number of the callers in
fast paths know for a fact their node is valid.  To avoid a comparison and
branch, this patch adds alloc_pages_exact_node() that only checks the nid
with VM_BUG_ON().  Callers that know their node is valid are then
converted.
Signed-off-by: NMel Gorman <mel@csn.ul.ie>
Reviewed-by: NChristoph Lameter <cl@linux-foundation.org>
Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: NPekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Paul Mundt <lethal@linux-sh.org>	[for the SLOB NUMA bits]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>