diff options
| author | Peter Zijlstra <[email protected]> | 2018-11-29 13:44:49 +0000 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2019-01-21 10:15:38 +0000 |
| commit | b061c38bef43406df8e73c5be06cbfacad5ee6ad (patch) | |
| tree | c031de9bb7878fd8a24cc0fb339151044e2fae12 /tools/perf/util/c++/clang.cpp | |
| parent | sched/wake_q: Fix wakeup ordering for wake_q (diff) | |
| download | kernel-b061c38bef43406df8e73c5be06cbfacad5ee6ad.tar.gz kernel-b061c38bef43406df8e73c5be06cbfacad5ee6ad.zip | |
futex: Fix (possible) missed wakeup
We must not rely on wake_q_add() to delay the wakeup; in particular
commit:
1d0dcb3ad9d3 ("futex: Implement lockless wakeups")
moved wake_q_add() before smp_store_release(&q->lock_ptr, NULL), which
could result in futex_wait() waking before observing ->lock_ptr ==
NULL and going back to sleep again.
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Fixes: 1d0dcb3ad9d3 ("futex: Implement lockless wakeups")
Signed-off-by: Ingo Molnar <[email protected]>
Diffstat (limited to 'tools/perf/util/c++/clang.cpp')
0 files changed, 0 insertions, 0 deletions