Tejun Heo ccea34b5d0 percpu: finer grained locking to break deadlock and allow atomic free ... Impact: fix deadlock and allow atomic free Percpu allocation always uses GFP_KERNEL and whole alloc/free paths were protected by single mutex. All percpu allocations have been from GFP_KERNEL-safe context and the original allocator had this assumption too. However, by protecting both alloc and free paths with the same mutex, the new allocator creates free -> alloc -> GFP_KERNEL dependency which the original allocator didn't have. This can lead to deadlock if free is called from FS or IO paths. Also, in general, allocators are expected to allow free to be called from atomic context. This patch implements finer grained locking to break the deadlock and allow atomic free. For details, please read the "Synchronization rules" comment. While at it, also add CONTEXT: to function comments to describe which context they expect to be called from and what they do to it. This problem was reported by Thomas Gleixner and Peter Zijlstra. http://thread.gmane.org/gmane.linux.kernel/802384 Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Thomas Gleixner <tglx@linutronix.de> Reported-by: Peter Zijlstra <peterz@infradead.org>		2009-03-07 14:46:35 +09:00
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allocpercpu.c	percpu: kill percpu_alloc() and friends	2009-02-20 16:29:08 +09:00
backing-dev.c	Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-01-06 17:10:04 -08:00
bootmem.c	bootmem, x86: further fixes for arch-specific bootmem wrapping	2009-03-01 16:06:56 +09:00
bounce.c	bounce: don't rely on a zeroed bio_vec list	2008-12-29 08:29:52 +01:00
dmapool.c	dmapool: enable debugging for CONFIG_SLUB_DEBUG_ON too	2008-04-28 08:58:20 -07:00
fadvise.c	[CVE-2009-0029] System call wrapper special cases	2009-01-14 14:15:18 +01:00
failslab.c	SLUB: failslab support	2008-12-29 11:27:46 +02:00
filemap_xip.c	x86, mm: dont use non-temporal stores in pagecache accesses	2009-03-02 11:06:49 +01:00
filemap.c	x86, mm: dont use non-temporal stores in pagecache accesses	2009-03-02 11:06:49 +01:00
fremap.c	Do not account for the address space used by hugetlbfs using VM_ACCOUNT	2009-02-10 10:48:42 -08:00
highmem.c	x86, pat: avoid highmem cache attribute aliasing	2008-08-15 17:22:57 +02:00
hugetlb.c	Do not account for hugetlbfs quota at mmap() time if mapping [SHM|MAP]_NORESERVE	2009-02-11 12:38:09 -08:00
internal.h	mm: make get_user_pages() interruptible	2009-01-06 15:59:08 -08:00
Kconfig	Remove obsolete CONFIG_RESOURCES_64BIT	2009-01-06 15:59:14 -08:00
maccess.c	kgdb: fix optional arch functions and probe_kernel_*	2008-04-17 20:05:39 +02:00
madvise.c	[CVE-2009-0029] System call wrappers part 14	2009-01-14 14:15:24 +01:00
Makefile	percpu: implement new dynamic percpu allocator	2009-02-20 16:29:08 +09:00
memcontrol.c	memcg: NULL pointer dereference at rmdir on some NUMA systems	2009-01-29 18:04:44 -08:00
memory_hotplug.c	mm: remove GFP_HIGHUSER_PAGECACHE	2009-01-06 15:59:01 -08:00
memory.c	do_wp_page: fix regression with execute in place	2009-02-05 12:56:48 -08:00
mempolicy.c	[CVE-2009-0029] System call wrappers part 28	2009-01-14 14:15:30 +01:00
mempool.c	spelling fixes: mm/	2007-10-20 01:27:18 +02:00
migrate.c	migration: migrate_vmas should check "vma"	2009-02-11 14:25:34 -08:00
mincore.c	[CVE-2009-0029] System call wrappers part 14	2009-01-14 14:15:24 +01:00
mlock.c	Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-02-17 14:27:39 -08:00
mm_init.c	mm: mminit_loglevel cannot be __meminitdata anymore	2008-08-20 15:40:30 -07:00
mmap.c	mm: rearrange exit_mmap() to unlock before arch_exit_mmap	2009-02-11 14:25:37 -08:00
mmu_notifier.c	mmu-notifiers: core	2008-07-28 16:30:21 -07:00
mmzone.c	mm: mark the correct zone as full when scanning zonelists	2008-09-13 14:41:52 -07:00
mprotect.c	Do not account for the address space used by hugetlbfs using VM_ACCOUNT	2009-02-10 10:48:42 -08:00
mremap.c	[CVE-2009-0029] System call wrappers part 13	2009-01-14 14:15:23 +01:00
msync.c	[CVE-2009-0029] System call wrappers part 13	2009-01-14 14:15:23 +01:00
nommu.c	uclinux: add process name to allocation error message	2009-01-27 16:42:03 +10:00
oom_kill.c	memcg: avoid deadlock caused by race between oom and cpuset_attach	2009-01-08 08:31:09 -08:00
page_alloc.c	mm: fix memmap init for handling memory hole	2009-02-18 15:37:55 -08:00
page_cgroup.c	memcg: use __GFP_NOWARN in page cgroup allocation	2009-02-11 14:25:35 -08:00
page_io.c	block: fix bad definition of BIO_RW_SYNC	2009-02-18 10:32:00 +01:00
page_isolation.c	memory hotplug: fix page_zone() calculation in test_pages_isolated()	2008-11-06 15:41:19 -08:00
page-writeback.c	mm: task dirty accounting fix	2009-02-18 15:37:54 -08:00
pagewalk.c	pagemap: pass mm into pagewalkers	2008-06-12 18:05:41 -07:00
pdflush.c	cpumask: convert mm/	2009-01-01 10:12:29 +10:30
percpu.c	percpu: finer grained locking to break deadlock and allow atomic free	2009-03-07 14:46:35 +09:00
prio_tree.c	spelling fixes: mm/	2007-10-20 01:27:18 +02:00
quicklist.c	mm: size of quicklists shouldn't be proportional to the number of CPUs	2008-09-02 19:21:38 -07:00
readahead.c	vmscan: split LRU lists into anon & file sets	2008-10-20 08:50:25 -07:00
rmap.c	mm: fix mlocked page counter mismatch	2009-02-11 14:25:35 -08:00
shmem_acl.c	[PATCH] sanitize ->permission() prototype	2008-07-26 20:53:14 -04:00
shmem.c	shmem: fix shared anonymous accounting	2009-02-25 12:21:42 -08:00
slab.c	mm: Export symbol ksize()	2009-02-12 17:50:46 +02:00
slob.c	mm: Export symbol ksize()	2009-02-12 17:50:46 +02:00
slub.c	mm: Export symbol ksize()	2009-02-12 17:50:46 +02:00
sparse-vmemmap.c	vmemmap: warn about page_structs with remote distance	2008-11-06 15:41:19 -08:00
sparse.c	meminit section warnings	2008-11-30 10:03:35 -08:00
swap_state.c	memcg: mem+swap controller core	2009-01-08 08:31:05 -08:00
swap.c	memcg: add zone_reclaim_stat	2009-01-08 08:31:08 -08:00
swapfile.c	PM/hibernate: fix "swap breaks after hibernation failures"	2009-02-21 14:17:17 -08:00
thrash.c	Bug in mm/thrash.c function grab_swap_token()	2007-05-11 08:29:32 -07:00
truncate.c	mmap: handle mlocked pages during map, remap, unmap	2008-10-20 08:52:31 -07:00
util.c	slab: introduce kzfree()	2009-02-20 17:57:48 -08:00
vmalloc.c	Merge branch 'x86/core' into core/percpu	2009-03-04 02:29:19 +01:00
vmscan.c	swsusp: clean up shrink_all_zones()	2009-02-21 14:17:17 -08:00
vmstat.c	cpumask: convert mm/	2009-01-01 10:12:29 +10:30