linux-stable.git/mm/slab.c, branch linux-3.9.y

taint: add explicit flag to show whether lock dep is still OK.

2013-01-21T06:47:57+00:00

Fix up all callers as they were before, with make one change: an
unsigned module taints the kernel, but doesn't turn off lockdep.

Signed-off-by: Rusty Russell

memcg: add comments clarifying aspects of cache attribute propagation

2012-12-18T23:02:15+00:00

This patch clarifies two aspects of cache attribute propagation.

First, the expected context for the for_each_memcg_cache macro in
memcontrol.h.  The usages already in the codebase are safe.  In mm/slub.c,
it is trivially safe because the lock is acquired right before the loop.
In mm/slab.c, it is less so: the lock is acquired by an outer function a
few steps back in the stack, so a VM_BUG_ON() is added to make sure it is
indeed safe.

A comment is also added to detail why we are returning the value of the
parent cache and ignoring the children's when we propagate the attributes.

Signed-off-by: Glauber Costa 
Cc: Michal Hocko 
Cc: Kamezawa Hiroyuki 
Cc: Johannes Weiner 
Acked-by: David Rientjes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

slab: propagate tunable values

2012-12-18T23:02:14+00:00

SLAB allows us to tune a particular cache behavior with tunables.  When
creating a new memcg cache copy, we'd like to preserve any tunables the
parent cache already had.

This could be done by an explicit call to do_tune_cpucache() after the
cache is created.  But this is not very convenient now that the caches are
created from common code, since this function is SLAB-specific.

Another method of doing that is taking advantage of the fact that
do_tune_cpucache() is always called from enable_cpucache(), which is
called at cache initialization.  We can just preset the values, and then
things work as expected.

It can also happen that a root cache has its tunables updated during
normal system operation.  In this case, we will propagate the change to
all caches that are already active.

This change will require us to move the assignment of root_cache in
memcg_params a bit earlier.  We need this to be already set - which
memcg_kmem_register_cache will do - when we reach __kmem_cache_create()

Signed-off-by: Glauber Costa 
Cc: Christoph Lameter 
Cc: David Rientjes 
Cc: Frederic Weisbecker 
Cc: Greg Thelen 
Cc: Johannes Weiner 
Cc: JoonSoo Kim 
Cc: KAMEZAWA Hiroyuki 
Cc: Mel Gorman 
Cc: Michal Hocko 
Cc: Pekka Enberg 
Cc: Rik van Riel 
Cc: Suleiman Souhlal 
Cc: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: destroy memcg caches

2012-12-18T23:02:14+00:00

Implement destruction of memcg caches.  Right now, only caches where our
reference counter is the last remaining are deleted.  If there are any
other reference counters around, we just leave the caches lying around
until they go away.

When that happens, a destruction function is called from the cache code.
Caches are only destroyed in process context, so we queue them up for
later processing in the general case.

Signed-off-by: Glauber Costa 
Cc: Christoph Lameter 
Cc: David Rientjes 
Cc: Frederic Weisbecker 
Cc: Greg Thelen 
Cc: Johannes Weiner 
Cc: JoonSoo Kim 
Cc: KAMEZAWA Hiroyuki 
Cc: Mel Gorman 
Cc: Michal Hocko 
Cc: Pekka Enberg 
Cc: Rik van Riel 
Cc: Suleiman Souhlal 
Cc: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

sl[au]b: allocate objects from memcg cache

2012-12-18T23:02:14+00:00

We are able to match a cache allocation to a particular memcg.  If the
task doesn't change groups during the allocation itself - a rare event,
this will give us a good picture about who is the first group to touch a
cache page.

This patch uses the now available infrastructure by calling
memcg_kmem_get_cache() before all the cache allocations.

Signed-off-by: Glauber Costa 
Cc: Christoph Lameter 
Cc: David Rientjes 
Cc: Frederic Weisbecker 
Cc: Greg Thelen 
Cc: Johannes Weiner 
Cc: JoonSoo Kim 
Cc: KAMEZAWA Hiroyuki 
Cc: Mel Gorman 
Cc: Michal Hocko 
Cc: Pekka Enberg 
Cc: Rik van Riel 
Cc: Suleiman Souhlal 
Cc: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

sl[au]b: always get the cache from its page in kmem_cache_free()

2012-12-18T23:02:14+00:00

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: Glauber Costa 
Cc: Christoph Lameter 
Cc: David Rientjes 
Cc: Frederic Weisbecker 
Cc: Greg Thelen 
Cc: Johannes Weiner 
Cc: JoonSoo Kim 
Cc: KAMEZAWA Hiroyuki 
Cc: Mel Gorman 
Cc: Michal Hocko 
Cc: Pekka Enberg 
Cc: Rik van Riel 
Cc: Suleiman Souhlal 
Cc: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

slab: annotate on-slab caches nodelist locks

2012-12-18T23:02:13+00:00

We currently provide lockdep annotation for kmalloc caches, and also
caches that have SLAB_DEBUG_OBJECTS enabled.  The reason for this is that
we can quite frequently nest in the l3->list_lock lock, which is not
something trivial to avoid.

My proposal with this patch, is to extend this to caches whose slab
management object lives within the slab as well ("on_slab").  The need for
this arose in the context of testing kmemcg-slab patches.  With such
patchset, we can have per-memcg kmalloc caches.  So the same path that led
to nesting between kmalloc caches will could then lead to in-memcg
nesting.  Because they are not annotated, lockdep will trigger.

Signed-off-by: Glauber Costa 
Cc: Christoph Lameter 
Cc: David Rientjes 
Cc: Frederic Weisbecker 
Cc: Greg Thelen 
Cc: Johannes Weiner 
Cc: JoonSoo Kim 
Cc: KAMEZAWA Hiroyuki 
Cc: Mel Gorman 
Cc: Michal Hocko 
Cc: Pekka Enberg 
Cc: Rik van Riel 
Cc: Suleiman Souhlal 
Cc: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/sl[aou]b: Common alignment code

2012-12-11T10:14:28+00:00

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: Christoph Lameter 
Signed-off-by: Pekka Enberg

slab: Use the new create_boot_cache function to simplify bootstrap

2012-12-11T10:14:27+00:00

Simplify setup and reduce code in kmem_cache_init(). This allows us to
get rid of initarray_cache as well as the manual setup code for
the kmem_cache and kmem_cache_node arrays during bootstrap.

We introduce a new bootstrap state "PARTIAL" for slab that signals the
creation of a kmem_cache boot cache.

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

mm, sl[au]b: create common functions for boot slab creation

2012-12-11T10:14:27+00:00

Use a special function to create kmalloc caches and use that function in
SLAB and SLUB.

Acked-by: Joonsoo Kim 
Reviewed-by: Glauber Costa 
Acked-by: David Rientjes 
Signed-off-by: Christoph Lameter 
Signed-off-by: Pekka Enberg