diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2015-11-15 20:33:29 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-11-23 09:48:19 +0100 |
| commit | dd2e3121e3cb16d03a6e3f2db48f260f046f39c2 (patch) | |
| tree | d184d7819e46df31dd7088c564e10d6ce213ccf3 /kernel/stop_machine.c | |
| parent | 6fa3b826bcb3309157166e6e523a4be236fe267a (diff) | |
| download | linux-dd2e3121e3cb16d03a6e3f2db48f260f046f39c2.tar.gz linux-dd2e3121e3cb16d03a6e3f2db48f260f046f39c2.tar.bz2 linux-dd2e3121e3cb16d03a6e3f2db48f260f046f39c2.zip | |
stop_machine: Shift the 'done != NULL' check from cpu_stop_signal_done() to callers
Change cpu_stop_queue_work() and cpu_stopper_thread() to check done != NULL
before cpu_stop_signal_done(done). This makes the code more clean imo, note
that cpu_stopper_thread() has to do this check anyway.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Milos Vyletel <milos@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20151115193329.GA8274@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/stop_machine.c')
| -rw-r--r-- | kernel/stop_machine.c | 18 |
1 files changed, 8 insertions, 10 deletions
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 09eb83fc9f0e..7ff7acee2c76 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -64,10 +64,8 @@ static void cpu_stop_init_done(struct cpu_stop_done *done, unsigned int nr_todo) /* signal completion unless @done is NULL */ static void cpu_stop_signal_done(struct cpu_stop_done *done) { - if (done) { - if (atomic_dec_and_test(&done->nr_todo)) - complete(&done->completion); - } + if (atomic_dec_and_test(&done->nr_todo)) + complete(&done->completion); } static void __cpu_stop_queue_work(struct cpu_stopper *stopper, @@ -88,7 +86,7 @@ static bool cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work) enabled = stopper->enabled; if (enabled) __cpu_stop_queue_work(stopper, work); - else + else if (work->done) cpu_stop_signal_done(work->done); spin_unlock_irqrestore(&stopper->lock, flags); @@ -457,12 +455,12 @@ repeat: /* cpu stop callbacks are not allowed to sleep */ preempt_disable(); - ret = fn(arg); - if (ret && done) - done->ret = ret; - cpu_stop_signal_done(done); - + if (done) { + if (ret) + done->ret = ret; + cpu_stop_signal_done(done); + } /* restore preemption and check it's still balanced */ preempt_enable(); WARN_ONCE(preempt_count(), |