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2014-08-07mm, thp: move invariant bug check out of loop in __split_huge_page_mapWaiman Long1-2/+2
In __split_huge_page_map(), the check for page_mapcount(page) is invariant within the for loop. Because of the fact that the macro is implemented using atomic_read(), the redundant check cannot be optimized away by the compiler leading to unnecessary read to the page structure. This patch moves the invariant bug check out of the loop so that it will be done only once. On a 3.16-rc1 based kernel, the execution time of a microbenchmark that broke up 1000 transparent huge pages using munmap() had an execution time of 38,245us and 38,548us with and without the patch respectively. The performance gain is about 1%. Signed-off-by: Waiman Long <Waiman.Long@hp.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Scott J Norton <scott.norton@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm, CMA: clean-up log messageJoonsoo Kim1-2/+2
We don't need explicit 'CMA:' prefix, since we already define prefix 'cma:' in pr_fmt. So remove it. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Alexander Graf <agraf@suse.de> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Gleb Natapov <gleb@kernel.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm, CMA: change cma_declare_contiguous() to obey coding conventionJoonsoo Kim1-6/+7
Conventionally, we put output param to the end of param list and put the 'base' ahead of 'size', but cma_declare_contiguous() doesn't look like that, so change it. Additionally, move down cma_areas reference code to the position where it is really needed. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Alexander Graf <agraf@suse.de> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Gleb Natapov <gleb@kernel.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm, CMA: clean-up CMA allocation error pathJoonsoo Kim1-3/+4
We can remove one call sites for clear_cma_bitmap() if we first call it before checking error number. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Michal Nazarewicz <mina86@mina86.com> Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Alexander Graf <agraf@suse.de> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Gleb Natapov <gleb@kernel.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07CMA: generalize CMA reserved area management functionalityJoonsoo Kim3-0/+345
Currently, there are two users on CMA functionality, one is the DMA subsystem and the other is the KVM on powerpc. They have their own code to manage CMA reserved area even if they looks really similar. From my guess, it is caused by some needs on bitmap management. KVM side wants to maintain bitmap not for 1 page, but for more size. Eventually it use bitmap where one bit represents 64 pages. When I implement CMA related patches, I should change those two places to apply my change and it seem to be painful to me. I want to change this situation and reduce future code management overhead through this patch. This change could also help developer who want to use CMA in their new feature development, since they can use CMA easily without copying & pasting this reserved area management code. In previous patches, we have prepared some features to generalize CMA reserved area management and now it's time to do it. This patch moves core functions to mm/cma.c and change DMA APIs to use these functions. There is no functional change in DMA APIs. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Acked-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Alexander Graf <agraf@suse.de> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Gleb Natapov <gleb@kernel.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm/internal.h: use nth_pageFabian Frederick1-1/+1
Use nth_page instead of pfn_to_page(page_to_pfn Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm: page_alloc: simplify drain_zone_pages by using min()Michal Nazarewicz1-6/+2
Instead of open-coding getting minimal value of two, just use min macro. That is why it is there for. While changing the function also change type of batch local variable to match type of per_cpu_pages::batch (which is int). Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mem-hotplug: introduce MMOP_OFFLINE to replace the hard coding -1Tang Chen1-3/+6
In store_mem_state(), we have: ... 334 else if (!strncmp(buf, "offline", min_t(int, count, 7))) 335 online_type = -1; ... 355 case -1: 356 ret = device_offline(&mem->dev); 357 break; ... Here, "offline" is hard coded as -1. This patch does the following renaming: ONLINE_KEEP -> MMOP_ONLINE_KEEP ONLINE_KERNEL -> MMOP_ONLINE_KERNEL ONLINE_MOVABLE -> MMOP_ONLINE_MOVABLE and introduces MMOP_OFFLINE = -1 to avoid hard coding. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Cc: Hu Tao <hutao@cn.fujitsu.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm/memory.c: use entry = ACCESS_ONCE(*pte) in handle_pte_fault()Hugh Dickins1-1/+1
Use ACCESS_ONCE() in handle_pte_fault() when getting the entry or orig_pte upon which all subsequent decisions and pte_same() tests will be made. I have no evidence that its lack is responsible for the mm/filemap.c:202 BUG_ON(page_mapped(page)) in __delete_from_page_cache() found by trinity, and I am not optimistic that it will fix it. But I have found no other explanation, and ACCESS_ONCE() here will surely not hurt. If gcc does re-access the pte before passing it down, then that would be disastrous for correct page fault handling, and certainly could explain the page_mapped() BUGs seen (concurrent fault causing page to be mapped in a second time on top of itself: mapcount 2 for a single pte). Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07vmalloc: use rcu list iterator to reduce vmap_area_lock contentionJoonsoo Kim1-3/+3
Richard Yao reported a month ago that his system have a trouble with vmap_area_lock contention during performance analysis by /proc/meminfo. Andrew asked why his analysis checks /proc/meminfo stressfully, but he didn't answer it. https://lkml.org/lkml/2014/4/10/416 Although I'm not sure that this is right usage or not, there is a solution reducing vmap_area_lock contention with no side-effect. That is just to use rcu list iterator in get_vmalloc_info(). rcu can be used in this function because all RCU protocol is already respected by writers, since Nick Piggin commit db64fe02258f1 ("mm: rewrite vmap layer") back in linux-2.6.28 Specifically : insertions use list_add_rcu(), deletions use list_del_rcu() and kfree_rcu(). Note the rb tree is not used from rcu reader (it would not be safe), only the vmap_area_list has full RCU protection. Note that __purge_vmap_area_lazy() already uses this rcu protection. rcu_read_lock(); list_for_each_entry_rcu(va, &vmap_area_list, list) { if (va->flags & VM_LAZY_FREE) { if (va->va_start < *start) *start = va->va_start; if (va->va_end > *end) *end = va->va_end; nr += (va->va_end - va->va_start) >> PAGE_SHIFT; list_add_tail(&va->purge_list, &valist); va->flags |= VM_LAZY_FREEING; va->flags &= ~VM_LAZY_FREE; } } rcu_read_unlock(); Peter: : While rcu list traversal over the vmap_area_list is safe, this may : arrive at different results than the spinlocked version. The rcu list : traversal version will not be a 'snapshot' of a single, valid instant : of the entire vmap_area_list, but rather a potential amalgam of : different list states. Joonsoo: : Yes, you are right, but I don't think that we should be strict here. : Meminfo is already not a 'snapshot' at specific time. While we try to get : certain stats, the other stats can change. And, although we may arrive at : different results than the spinlocked version, the difference would not be : large and would not make serious side-effect. [edumazet@google.com: add more commit description] Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reported-by: Richard Yao <ryao@gentoo.org> Acked-by: Eric Dumazet <edumazet@google.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Zhang Yanfei <zhangyanfei.yes@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm/page_alloc.c: unexport alloc_pages_exact_nid()Andrew Morton1-1/+0
It is only called by mm/page_cgroup.c whcih cannot be modular. Reported-by: David Rientjes <rientjes@google.com> Cc: Fabian Frederick <fabf@skynet.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm/page_alloc.c: add __meminit to alloc_pages_exact_nid()Fabian Frederick1-1/+1
alloc_pages_exact_nid() is only called by __meminit alloc_page_cgroup() Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm/memory_hotplug.c: add __meminit to grow_zone_span/grow_pgdat_spanFabian Frederick1-4/+4
grow_zone_span and grow_pgdat_span are only called by __meminit __add_zone Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Toshi Kani <toshi.kani@hp.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm/readahead.c: remove unused file_ra_state from count_history_pagesFabian Frederick1-2/+1
count_history_pages does only call page_cache_prev_hole in rcu_lock context using address_space mapping. There's no need to have file_ra_state here. Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Fengguang Wu <fengguang.wu@intel.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: convert last use of __FUNCTION__ to __func__Joe Perches1-1/+1
Just about all of these have been converted to __func__, so convert the last use. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: fix the alias count (via sysfs) of slab cacheGu Zheng1-1/+1
We mark some slab caches (e.g. kmem_cache_node) as unmergeable by setting refcount to -1, and their alias should be 0, not refcount-1, so correct it here. Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm, slub: fix some indenting in cmpxchg_double_slab()Dan Carpenter1-6/+6
The return statement goes with the cmpxchg_double() condition so it needs to be indented another tab. Also these days the fashion is to line function parameters up, and it looks nicer that way because then the "freelist_new" is not at the same indent level as the "return 1;". Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Christoph Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm/slab.c: fix commentsWang Sheng-Hui1-4/+5
Current struct kmem_cache has no 'lock' field, and slab page is managed by struct kmem_cache_node, which has 'list_lock' field. Clean up the related comment. Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm: move slab related stuff from util.c to slab_common.cAndrey Ryabinin2-102/+101
Functions krealloc(), __krealloc(), kzfree() belongs to slab API, so should be placed in slab_common.c Also move slab allocator's tracepoints defenitions to slab_common.c No functional changes here. Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slub: avoid duplicate creation on the first objectWei Yang1-8/+11
When a kmem_cache is created with ctor, each object in the kmem_cache will be initialized before ready to use. While in slub implementation, the first object will be initialized twice. This patch reduces the duplication of initialization of the first object. Fix commit 7656c72b ("SLUB: add macros for scanning objects in a slab"). Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: change int to size_t for representing allocation sizeJoonsoo Kim1-4/+4
It is better to represent allocation size in size_t rather than int. So change it. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Lameter <cl@linux.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: remove BAD_ALIEN_MAGICJoonsoo Kim1-3/+1
BAD_ALIEN_MAGIC value isn't used anymore. So remove it. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: remove a useless lockdep annotationJoonsoo Kim1-153/+0
Now, there is no code to hold two lock simultaneously, since we don't call slab_destroy() with holding any lock. So, lockdep annotation is useless now. Remove it. v2: don't remove BAD_ALIEN_MAGIC in this patch. It will be removed in the following patch. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: destroy a slab without holding any alien cache lockJoonsoo Kim1-7/+13
I haven't heard that this alien cache lock is contended, but to reduce chance of contention would be better generally. And with this change, we can simplify complex lockdep annotation in slab code. In the following patch, it will be implemented. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: use the lock on alien_cache, instead of the lock on array_cacheJoonsoo Kim1-17/+8
Now, we have separate alien_cache structure, so it'd be better to hold the lock on alien_cache while manipulating alien_cache. After that, we don't need the lock on array_cache, so remove it. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: introduce alien_cacheJoonsoo Kim2-42/+68
Currently, we use array_cache for alien_cache. Although they are mostly similar, there is one difference, that is, need for spinlock. We don't need spinlock for array_cache itself, but to use array_cache for alien_cache, array_cache structure should have spinlock. This is needless overhead, so removing it would be better. This patch prepare it by introducing alien_cache and using it. In the following patch, we remove spinlock in array_cache. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: factor out initialization of array cacheJoonsoo Kim1-14/+19
Factor out initialization of array cache to use it in following patch. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: defer slab_destroy in free_block()Joonsoo Kim1-19/+41
In free_block(), if freeing object makes new free slab and number of free_objects exceeds free_limit, we start to destroy this new free slab with holding the kmem_cache node lock. Holding the lock is useless and, generally, holding a lock as least as possible is good thing. I never measure performance effect of this, but we'd be better not to hold the lock as much as possible. Commented by Christoph: This is also good because kmem_cache_free is no longer called while holding the node lock. So we avoid one case of recursion. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: move up code to get kmem_cache_node in free_block()Joonsoo Kim1-2/+1
node isn't changed, so we don't need to retreive this structure everytime we move the object. Maybe compiler do this optimization, but making it explicitly is better. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: add unlikely macro to help compilerJoonsoo Kim1-1/+1
This patchset does some cleanup and tries to remove lockdep annotation. Patches 1~2 are just for really really minor improvement. Patches 3~9 are for clean-up and removing lockdep annotation. There are two cases that lockdep annotation is needed in SLAB. 1) holding two node locks 2) holding two array cache(alien cache) locks I looked at the code and found that we can avoid these cases without any negative effect. 1) occurs if freeing object makes new free slab and we decide to destroy it. Although we don't need to hold the lock during destroying a slab, current code do that. Destroying a slab without holding the lock would help the reduction of the lock contention. To do it, I change the implementation that new free slab is destroyed after releasing the lock. 2) occurs on similar situation. When we free object from non-local node, we put this object to alien cache with holding the alien cache lock. If alien cache is full, we try to flush alien cache to proper node cache, and, in this time, new free slab could be made. Destroying it would be started and we will free metadata object which comes from another node. In this case, we need another node's alien cache lock to free object. This forces us to hold two array cache locks and then we need lockdep annotation although they are always different locks and deadlock cannot be possible. To prevent this situation, I use same way as 1). In this way, we can avoid 1) and 2) cases, and then, can remove lockdep annotation. As short stat noted, this makes SLAB code much simpler. This patch (of 9): slab_should_failslab() is called on every allocation, so to optimize it is reasonable. We normally don't allocate from kmem_cache. It is just used when new kmem_cache is created, so it's very rare case. Therefore, add unlikely macro to help compiler optimization. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm: slub: SLUB_DEBUG=n: use the same alloc/free hooks as for SLUB_DEBUG=yAndrey Ryabinin1-61/+36
There are two versions of alloc/free hooks now - one for CONFIG_SLUB_DEBUG=y and another one for CONFIG_SLUB_DEBUG=n. I see no reason why calls to other debugging subsystems (LOCKDEP, DEBUG_ATOMIC_SLEEP, KMEMCHECK and FAILSLAB) are hidden under SLUB_DEBUG. All this features should work regardless of SLUB_DEBUG config, as all of them already have own Kconfig options. This also fixes failslab for CONFIG_SLUB_DEBUG=n configuration. It simply has not worked before because should_failslab() call was in a hook hidden under "#ifdef CONFIG_SLUB_DEBUG #else". Note: There is one concealed change in allocation path for SLUB_DEBUG=n and all other debugging features disabled. The might_sleep_if() call can generate some code even if DEBUG_ATOMIC_SLEEP=n. For PREEMPT_VOLUNTARY=y might_sleep() inserts _cond_resched() call, but I think it should be ok. Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm, slub: mark resiliency_test as init textDavid Rientjes1-1/+1
resiliency_test() is only called for bootstrap, so it may be moved to init.text and freed after boot. Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm: slab.h: wrap the whole file with guarding macroAndrey Ryabinin1-1/+2
Guarding section: #ifndef MM_SLAB_H #define MM_SLAB_H ... #endif currently doesn't cover the whole mm/slab.h. It seems like it was done unintentionally. Wrap the whole file by moving closing #endif to the end of it. Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> Acked-by: Christoph Lameter <cl@linux.com> Acked-by: David Rientjes <rientjes@google.com> Reviewed-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab: use get_node() and kmem_cache_node() functionsChristoph Lameter1-93/+80
Use the two functions to simplify the code avoiding numerous explicit checks coded checking for a certain node to be online. Get rid of various repeated calculations of kmem_cache_node structures. [akpm@linux-foundation.org: fix build] Signed-off-by: Christoph Lameter <cl@linux.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slub: use new node functionsChristoph Lameter1-49/+29
Make use of the new node functions in mm/slab.h to reduce code size and simplify. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Christoph Lameter <cl@linux.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07slab common: add functions for kmem_cache_node accessChristoph Lameter2-6/+16
The patchset provides two new functions in mm/slab.h and modifies SLAB and SLUB to use these. The kmem_cache_node structure is shared between both allocators and the use of common accessors will allow us to move more code into slab_common.c in the future. This patch (of 3): These functions allow to eliminate repeatedly used code in both SLAB and SLUB and also allow for the insertion of debugging code that may be needed in the development process. Signed-off-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-07mm/slab.c: add __init to init_lock_keysFabian Frederick1-2/+2
init_lock_keys is only called by __init kmem_cache_init_late Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Christoph Lameter <cl@linux.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-05Merge branch 'sched-core-for-linus' of ↵Linus Torvalds2-23/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: - Move the nohz kick code out of the scheduler tick to a dedicated IPI, from Frederic Weisbecker. This necessiated quite some background infrastructure rework, including: * Clean up some irq-work internals * Implement remote irq-work * Implement nohz kick on top of remote irq-work * Move full dynticks timer enqueue notification to new kick * Move multi-task notification to new kick * Remove unecessary barriers on multi-task notification - Remove proliferation of wait_on_bit() action functions and allow wait_on_bit_action() functions to support a timeout. (Neil Brown) - Another round of sched/numa improvements, cleanups and fixes. (Rik van Riel) - Implement fast idling of CPUs when the system is partially loaded, for better scalability. (Tim Chen) - Restructure and fix the CPU hotplug handling code that may leave cfs_rq and rt_rq's throttled when tasks are migrated away from a dead cpu. (Kirill Tkhai) - Robustify the sched topology setup code. (Peterz Zijlstra) - Improve sched_feat() handling wrt. static_keys (Jason Baron) - Misc fixes. * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits) sched/fair: Fix 'make xmldocs' warning caused by missing description sched: Use macro for magic number of -1 for setparam sched: Robustify topology setup sched: Fix sched_setparam() policy == -1 logic sched: Allow wait_on_bit_action() functions to support a timeout sched: Remove proliferation of wait_on_bit() action functions sched/numa: Revert "Use effective_load() to balance NUMA loads" sched: Fix static_key race with sched_feat() sched: Remove extra static_key*() function indirection sched/rt: Fix replenish_dl_entity() comments to match the current upstream code sched: Transform resched_task() into resched_curr() sched/deadline: Kill task_struct->pi_top_task sched: Rework check_for_tasks() sched/rt: Enqueue just unthrottled rt_rq back on the stack in __disable_runtime() sched/fair: Disable runtime_enabled on dying rq sched/numa: Change scan period code to match intent sched/numa: Rework best node setting in task_numa_migrate() sched/numa: Examine a task move when examining a task swap sched/numa: Simplify task_numa_compare() sched/numa: Use effective_load() to balance NUMA loads ...
2014-08-04Merge branch 'for-3.17' of ↵Linus Torvalds2-9/+33
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup changes from Tejun Heo: "Mostly changes to get the v2 interface ready. The core features are mostly ready now and I think it's reasonable to expect to drop the devel mask in one or two devel cycles at least for a subset of controllers. - cgroup added a controller dependency mechanism so that block cgroup can depend on memory cgroup. This will be used to finally support IO provisioning on the writeback traffic, which is currently being implemented. - The v2 interface now uses a separate table so that the interface files for the new interface are explicitly declared in one place. Each controller will explicitly review and add the files for the new interface. - cpuset is getting ready for the hierarchical behavior which is in the similar style with other controllers so that an ancestor's configuration change doesn't change the descendants' configurations irreversibly and processes aren't silently migrated when a CPU or node goes down. All the changes are to the new interface and no behavior changed for the multiple hierarchies" * 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (29 commits) cpuset: fix the WARN_ON() in update_nodemasks_hier() cgroup: initialize cgrp_dfl_root_inhibit_ss_mask from !->dfl_files test cgroup: make CFTYPE_ONLY_ON_DFL and CFTYPE_NO_ internal to cgroup core cgroup: distinguish the default and legacy hierarchies when handling cftypes cgroup: replace cgroup_add_cftypes() with cgroup_add_legacy_cftypes() cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes cgroup: split cgroup_base_files[] into cgroup_{dfl|legacy}_base_files[] cpuset: export effective masks to userspace cpuset: allow writing offlined masks to cpuset.cpus/mems cpuset: enable onlined cpu/node in effective masks cpuset: refactor cpuset_hotplug_update_tasks() cpuset: make cs->{cpus, mems}_allowed as user-configured masks cpuset: apply cs->effective_{cpus,mems} cpuset: initialize top_cpuset's configured masks at mount cpuset: use effective cpumask to build sched domains cpuset: inherit ancestor's masks if effective_{cpus, mems} becomes empty cpuset: update cs->effective_{cpus, mems} when config changes cpuset: update cpuset->effective_{cpus,mems} at hotplug cpuset: add cs->effective_cpus and cs->effective_mems cgroup: clean up sane_behavior handling ...
2014-08-04Merge branch 'for-3.17' of ↵Linus Torvalds1-2/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu Pull percpu updates from Tejun Heo: - Major reorganization of percpu header files which I think makes things a lot more readable and logical than before. - percpu-refcount is updated so that it requires explicit destruction and can be reinitialized if necessary. This was pulled into the block tree to replace the custom percpu refcnting implemented in blk-mq. - In the process, percpu and percpu-refcount got cleaned up a bit * 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (21 commits) percpu-refcount: implement percpu_ref_reinit() and percpu_ref_is_zero() percpu-refcount: require percpu_ref to be exited explicitly percpu-refcount: use unsigned long for pcpu_count pointer percpu-refcount: add helpers for ->percpu_count accesses percpu-refcount: one bit is enough for REF_STATUS percpu-refcount, aio: use percpu_ref_cancel_init() in ioctx_alloc() workqueue: stronger test in process_one_work() workqueue: clear POOL_DISASSOCIATED in rebind_workers() percpu: Use ALIGN macro instead of hand coding alignment calculation percpu: invoke __verify_pcpu_ptr() from the generic part of accessors and operations percpu: preffity percpu header files percpu: use raw_cpu_*() to define __this_cpu_*() percpu: reorder macros in percpu header files percpu: move {raw|this}_cpu_*() definitions to include/linux/percpu-defs.h percpu: move generic {raw|this}_cpu_*_N() definitions to include/asm-generic/percpu.h percpu: only allow sized arch overrides for {raw|this}_cpu_*() ops percpu: reorganize include/linux/percpu-defs.h percpu: move accessors from include/linux/percpu.h to percpu-defs.h percpu: include/asm-generic/percpu.h should contain only arch-overridable parts percpu: introduce arch_raw_cpu_ptr() ...
2014-07-31kexec: export free_huge_page to VMCOREINFOAtsushi Kumagai1-1/+1
PG_head_mask was added into VMCOREINFO to filter huge pages in b3acc56bfe1 ("kexec: save PG_head_mask in VMCOREINFO"), but makedumpfile still need another symbol to filter *hugetlbfs* pages. If a user hope to filter user pages, makedumpfile tries to exclude them by checking the condition whether the page is anonymous, but hugetlbfs pages aren't anonymous while they also be user pages. We know it's possible to detect them in the same way as PageHuge(), so we need the start address of free_huge_page(): int PageHuge(struct page *page) { if (!PageCompound(page)) return 0; page = compound_head(page); return get_compound_page_dtor(page) == free_huge_page; } For that reason, this patch changes free_huge_page() into public to export it to VMCOREINFO. Signed-off-by: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Acked-by: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-31mm: fix filemap.c pagecache_get_page() kernel-doc warningsRandy Dunlap1-5/+8
Fix kernel-doc warnings in mm/filemap.c: pagecache_get_page(): Warning(..//mm/filemap.c:1054): No description found for parameter 'cache_gfp_mask' Warning(..//mm/filemap.c:1054): No description found for parameter 'radix_gfp_mask' Warning(..//mm/filemap.c:1054): Excess function parameter 'gfp_mask' description in 'pagecache_get_page' Fixes: 2457aec63745 ("mm: non-atomically mark page accessed during page cache allocation where possible") [mgorman@suse.de: change everything] [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-31mm: debugfs: move rounddown_pow_of_two() out from do_fault pathAndrey Ryabinin1-9/+12
do_fault_around() expects fault_around_bytes rounded down to nearest page order. Instead of calling rounddown_pow_of_two every time in fault_around_pages()/fault_around_mask() we could do round down when user changes fault_around_bytes via debugfs interface. This also fixes bug when user set fault_around_bytes to 0. Result of rounddown_pow_of_two(0) is not defined, therefore fault_around_bytes == 0 doesn't work without this patch. Let's set fault_around_bytes to PAGE_SIZE if user sets to something less than PAGE_SIZE [akpm@linux-foundation.org: tweak code layout] Fixes: a9b0f861("mm: nominate faultaround area in bytes rather than page order") Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> Reported-by: Sasha Levin <sasha.levin@oracle.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: <stable@vger.kernel.org> [3.15.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-31memcg: oom_notify use-after-free fixMichal Hocko1-0/+4
Paul Furtado has reported the following GPF: general protection fault: 0000 [#1] SMP Modules linked in: ipv6 dm_mod xen_netfront coretemp hwmon x86_pkg_temp_thermal crc32_pclmul crc32c_intel ghash_clmulni_intel aesni_intel ablk_helper cryptd lrw gf128mul glue_helper aes_x86_64 microcode pcspkr ext4 jbd2 mbcache raid0 xen_blkfront CPU: 3 PID: 3062 Comm: java Not tainted 3.16.0-rc5 #1 task: ffff8801cfe8f170 ti: ffff8801d2ec4000 task.ti: ffff8801d2ec4000 RIP: e030:mem_cgroup_oom_synchronize+0x140/0x240 RSP: e02b:ffff8801d2ec7d48 EFLAGS: 00010283 RAX: 0000000000000001 RBX: ffff88009d633800 RCX: 000000000000000e RDX: fffffffffffffffe RSI: ffff88009d630200 RDI: ffff88009d630200 RBP: ffff8801d2ec7da8 R08: 0000000000000012 R09: 00000000fffffffe R10: 0000000000000000 R11: 0000000000000000 R12: ffff88009d633800 R13: ffff8801d2ec7d48 R14: dead000000100100 R15: ffff88009d633a30 FS: 00007f1748bb4700(0000) GS:ffff8801def80000(0000) knlGS:0000000000000000 CS: e033 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00007f4110300308 CR3: 00000000c05f7000 CR4: 0000000000002660 Call Trace: pagefault_out_of_memory+0x18/0x90 mm_fault_error+0xa9/0x1a0 __do_page_fault+0x478/0x4c0 do_page_fault+0x2c/0x40 page_fault+0x28/0x30 Code: 44 00 00 48 89 df e8 40 ca ff ff 48 85 c0 49 89 c4 74 35 4c 8b b0 30 02 00 00 4c 8d b8 30 02 00 00 4d 39 fe 74 1b 0f 1f 44 00 00 <49> 8b 7e 10 be 01 00 00 00 e8 42 d2 04 00 4d 8b 36 4d 39 fe 75 RIP mem_cgroup_oom_synchronize+0x140/0x240 Commit fb2a6fc56be6 ("mm: memcg: rework and document OOM waiting and wakeup") has moved mem_cgroup_oom_notify outside of memcg_oom_lock assuming it is protected by the hierarchical OOM-lock. Although this is true for the notification part the protection doesn't cover unregistration of event which can happen in parallel now so mem_cgroup_oom_notify can see already unlinked and/or freed mem_cgroup_eventfd_list. Fix this by using memcg_oom_lock also in mem_cgroup_oom_notify. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=80881 Fixes: fb2a6fc56be6 (mm: memcg: rework and document OOM waiting and wakeup) Signed-off-by: Michal Hocko <mhocko@suse.cz> Reported-by: Paul Furtado <paulfurtado91@gmail.com> Tested-by: Paul Furtado <paulfurtado91@gmail.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: <stable@vger.kernel.org> [3.12+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-31hwpoison: call action_result() in failure path of hwpoison_user_mappings()Naoya Horiguchi1-2/+4
hwpoison_user_mappings() could fail for various reasons, so printk()s to print out the reasons should be done in each failure check inside hwpoison_user_mappings(). And currently we don't call action_result() when hwpoison_user_mappings() fails, which is not consistent with other exit points of memory error handler. So this patch fixes these messaging problems. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Chen Yucong <slaoub@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-31hwpoison: fix hugetlbfs/thp precheck in hwpoison_user_mappings()Naoya Horiguchi1-1/+7
A recent fix from Chen Yucong, commit 0bc1f8b0682c ("hwpoison: fix the handling path of the victimized page frame that belong to non-LRU") rejects going into unmapping operation for hugetlbfs/thp pages, which results in failing error containing on such pages. This patch fixes it. With this patch, hwpoison functional tests in mce-test testsuite pass. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Chen Yucong <slaoub@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-31mm, thp: do not allow thp faults to avoid cpuset restrictionsDavid Rientjes1-8/+8
The page allocator relies on __GFP_WAIT to determine if ALLOC_CPUSET should be set in allocflags. ALLOC_CPUSET controls if a page allocation should be restricted only to the set of allowed cpuset mems. Transparent hugepages clears __GFP_WAIT when defrag is disabled to prevent the fault path from using memory compaction or direct reclaim. Thus, it is unfairly able to allocate outside of its cpuset mems restriction as a side-effect. This patch ensures that ALLOC_CPUSET is only cleared when the gfp mask is truly GFP_ATOMIC by verifying it is also not a thp allocation. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Alex Thorlton <athorlton@sgi.com> Tested-by: Alex Thorlton <athorlton@sgi.com> Cc: Bob Liu <lliubbo@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Hedi Berriche <hedi@sgi.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-31mm/page-writeback.c: fix divide by zero in bdi_dirty_limits()Maxim Patlasov1-3/+3
Under memory pressure, it is possible for dirty_thresh, calculated by global_dirty_limits() in balance_dirty_pages(), to equal zero. Then, if strictlimit is true, bdi_dirty_limits() tries to resolve the proportion: bdi_bg_thresh : bdi_thresh = background_thresh : dirty_thresh by dividing by zero. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-29mm: fix page_alloc.c kernel-doc warningsRandy Dunlap1-6/+9
Fix kernel-doc warnings and function name in mm/page_alloc.c: Warning(..//mm/page_alloc.c:6074): No description found for parameter 'pfn' Warning(..//mm/page_alloc.c:6074): No description found for parameter 'mask' Warning(..//mm/page_alloc.c:6074): Excess function parameter 'start_bitidx' description in 'get_pfnblock_flags_mask' Warning(..//mm/page_alloc.c:6102): No description found for parameter 'pfn' Warning(..//mm/page_alloc.c:6102): No description found for parameter 'mask' Warning(..//mm/page_alloc.c:6102): Excess function parameter 'start_bitidx' description in 'set_pfnblock_flags_mask' Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-28Merge branch 'sched/urgent' into sched/core, to merge fixes before applying ↵Ingo Molnar8-51/+87
new changes Signed-off-by: Ingo Molnar <mingo@kernel.org>