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| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2015-02-27 17:57:09 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-03-01 09:45:06 +0100 |
| commit | 9d3e2d02f54160725d97f4ab1e1e8de493fbf33a (patch) | |
| tree | 41da77b461389a4e06a9b2a9c52adca8436f2de1 /kernel | |
| parent | 895c8b7b4623d4f55e260e5dee2574b4f7113105 (diff) | |
| download | lwn-9d3e2d02f54160725d97f4ab1e1e8de493fbf33a.tar.gz lwn-9d3e2d02f54160725d97f4ab1e1e8de493fbf33a.zip | |
locking/rtmutex: Set state back to running on error
The "usual" path is:
- rt_mutex_slowlock()
- set_current_state()
- task_blocks_on_rt_mutex() (ret 0)
- __rt_mutex_slowlock()
- sleep or not but do return with __set_current_state(TASK_RUNNING)
- back to caller.
In the early error case where task_blocks_on_rt_mutex() return
-EDEADLK we never change the task's state back to RUNNING. I
assume this is intended. Without this change after ww_mutex
using rt_mutex the selftest passes but later I get plenty of:
| bad: scheduling from the idle thread!
backtraces.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: afffc6c1805d ("locking/rtmutex: Optimize setting task running after being blocked")
Link: http://lkml.kernel.org/r/1425056229-22326-4-git-send-email-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/locking/rtmutex.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index e16e5542bf13..6357265a31ad 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -1193,6 +1193,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state, ret = __rt_mutex_slowlock(lock, state, timeout, &waiter); if (unlikely(ret)) { + __set_current_state(TASK_RUNNING); if (rt_mutex_has_waiters(lock)) remove_waiter(lock, &waiter); rt_mutex_handle_deadlock(ret, chwalk, &waiter); |