mm, fork: make dup_mmap wait for mmap_sem for write killable
authorMichal Hocko <mhocko@suse.com>
Mon, 23 May 2016 23:25:48 +0000 (16:25 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 24 May 2016 00:04:14 +0000 (17:04 -0700)
commit7c051267931a9be9c6620cc17b362bc6ee6dedc8
treef955cbab8e30abfc0fcd69eff3462d59c364cd5a
parent4e80153a6044bcd9a7d65c1ec4b1d1c44ba0ed6c
mm, fork: make dup_mmap wait for mmap_sem for write killable

dup_mmap needs to lock current's mm mmap_sem for write.  If the waiting
task gets killed by the oom killer it would block oom_reaper from
asynchronous address space reclaim and reduce the chances of timely OOM
resolving.  Wait for the lock in the killable mode and return with EINTR
if the task got killed while waiting.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.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>
kernel/fork.c