https://github.com/torvalds/linux
Revision 2f7dd7a4100ad4affcb141605bef178ab98ccb18 authored by Johannes Weiner on 02 October 2014, 23:16:57 UTC, committed by Linus Torvalds on 02 October 2014, 23:28:44 UTC
The cgroup iterators yield css objects that have not yet gone through css_online(), but they are not complete memcgs at this point and so the memcg iterators should not return them. Commit d8ad30559715 ("mm/memcg: iteration skip memcgs not yet fully initialized") set out to implement exactly this, but it uses CSS_ONLINE, a cgroup-internal flag that does not meet the ordering requirements for memcg, and so the iterator may skip over initialized groups, or return partially initialized memcgs. The cgroup core can not reasonably provide a clear answer on whether the object around the css has been fully initialized, as that depends on controller-specific locking and lifetime rules. Thus, introduce a memcg-specific flag that is set after the memcg has been initialized in css_online(), and read before mem_cgroup_iter() callers access the memcg members. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Tejun Heo <tj@kernel.org> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Hugh Dickins <hughd@google.com> Cc: Peter Zijlstra <peterz@infradead.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>
1 parent 55dacd2
Tip revision: 2f7dd7a4100ad4affcb141605bef178ab98ccb18 authored by Johannes Weiner on 02 October 2014, 23:16:57 UTC
mm: memcontrol: do not iterate uninitialized memcgs
mm: memcontrol: do not iterate uninitialized memcgs
Tip revision: 2f7dd7a
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drivers | ||
firmware | ||
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include | ||
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ipc | ||
kernel | ||
lib | ||
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net | ||
samples | ||
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.gitignore | -rw-r--r-- | 1.1 KB |
.mailmap | -rw-r--r-- | 4.7 KB |
COPYING | -rw-r--r-- | 18.3 KB |
CREDITS | -rw-r--r-- | 93.8 KB |
Kbuild | -rw-r--r-- | 2.5 KB |
Kconfig | -rw-r--r-- | 252 bytes |
MAINTAINERS | -rw-r--r-- | 279.9 KB |
Makefile | -rw-r--r-- | 52.8 KB |
README | -rw-r--r-- | 18.3 KB |
REPORTING-BUGS | -rw-r--r-- | 7.3 KB |
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