4eaf3f6439
Add global mutex zonelists_mutex to fix the possible race: CPU0 CPU1 CPU2 (1) zone->present_pages += online_pages; (2) build_all_zonelists(); (3) alloc_page(); (4) free_page(); (5) build_all_zonelists(); (6) __build_all_zonelists(); (7) zone->pageset = alloc_percpu(); In step (3,4), zone->pageset still points to boot_pageset, so bad things may happen if 2+ nodes are in this state. Even if only 1 node is accessing the boot_pageset, (3) may still consume too much memory to fail the memory allocations in step (7). Besides, atomic operation ensures alloc_percpu() in step (7) will never fail since there is a new fresh memory block added in step(6). [haicheng.li@linux.intel.com: hold zonelists_mutex when build_all_zonelists] Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Reviewed-by: Andi Kleen <andi.kleen@intel.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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.. | ||
backing-dev.c | ||
bootmem.c | ||
bounce.c | ||
compaction.c | ||
debug-pagealloc.c | ||
dmapool.c | ||
fadvise.c | ||
failslab.c | ||
filemap_xip.c | ||
filemap.c | ||
fremap.c | ||
highmem.c | ||
hugetlb.c | ||
hwpoison-inject.c | ||
init-mm.c | ||
internal.h | ||
Kconfig | ||
Kconfig.debug | ||
kmemcheck.c | ||
kmemleak-test.c | ||
kmemleak.c | ||
ksm.c | ||
maccess.c | ||
madvise.c | ||
Makefile | ||
memcontrol.c | ||
memory_hotplug.c | ||
memory-failure.c | ||
memory.c | ||
mempolicy.c | ||
mempool.c | ||
migrate.c | ||
mincore.c | ||
mlock.c | ||
mm_init.c | ||
mmap.c | ||
mmu_context.c | ||
mmu_notifier.c | ||
mmzone.c | ||
mprotect.c | ||
mremap.c | ||
msync.c | ||
nommu.c | ||
oom_kill.c | ||
page_alloc.c | ||
page_cgroup.c | ||
page_io.c | ||
page_isolation.c | ||
page-writeback.c | ||
pagewalk.c | ||
percpu_up.c | ||
percpu-km.c | ||
percpu-vm.c | ||
percpu.c | ||
prio_tree.c | ||
quicklist.c | ||
readahead.c | ||
rmap.c | ||
shmem.c | ||
slab.c | ||
slob.c | ||
slub.c | ||
sparse-vmemmap.c | ||
sparse.c | ||
swap_state.c | ||
swap.c | ||
swapfile.c | ||
thrash.c | ||
truncate.c | ||
util.c | ||
vmalloc.c | ||
vmscan.c | ||
vmstat.c |