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 <[email protected]> --- 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 09eb83f..7ff7ace 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(), -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
