Preparation to simplify the review of the next change. Add two simple helpers, __cpu_stop_queue_work() and cpu_stop_queue_two_works() which simply take a bit of code from their callers.
Signed-off-by: Oleg Nesterov <[email protected]> --- kernel/stop_machine.c | 37 ++++++++++++++++++++++++++----------- 1 files changed, 26 insertions(+), 11 deletions(-) diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 6a40209..688d6b3 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -73,21 +73,24 @@ static void cpu_stop_signal_done(struct cpu_stop_done *done, bool executed) } } +static void __cpu_stop_queue_work(struct cpu_stopper *stopper, + struct cpu_stop_work *work) +{ + list_add_tail(&work->list, &stopper->works); + wake_up_process(stopper->thread); +} + /* queue @work to @stopper. if offline, @work is completed immediately */ static void cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work) { struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu); - unsigned long flags; spin_lock_irqsave(&stopper->lock, flags); - - if (stopper->enabled) { - list_add_tail(&work->list, &stopper->works); - wake_up_process(stopper->thread); - } else + if (stopper->enabled) + __cpu_stop_queue_work(stopper, work); + else cpu_stop_signal_done(work->done, false); - spin_unlock_irqrestore(&stopper->lock, flags); } @@ -213,6 +216,16 @@ static int multi_cpu_stop(void *data) return err; } +static int cpu_stop_queue_two_works(int cpu1, struct cpu_stop_work *work1, + int cpu2, struct cpu_stop_work *work2) +{ + lg_double_lock(&stop_cpus_lock, cpu1, cpu2); + cpu_stop_queue_work(cpu1, work1); + cpu_stop_queue_work(cpu2, work2); + lg_double_unlock(&stop_cpus_lock, cpu1, cpu2); + + return 0; +} /** * stop_two_cpus - stops two cpus * @cpu1: the cpu to stop @@ -260,10 +273,12 @@ int stop_two_cpus(unsigned int cpu1, unsigned int cpu2, cpu_stop_fn_t fn, void * return -ENOENT; } - lg_double_lock(&stop_cpus_lock, cpu1, cpu2); - cpu_stop_queue_work(cpu1, &work1); - cpu_stop_queue_work(cpu2, &work2); - lg_double_unlock(&stop_cpus_lock, cpu1, cpu2); + if (cpu1 > cpu2) + swap(cpu1, cpu2); + if (cpu_stop_queue_two_works(cpu1, &work1, cpu2, &work2)) { + preempt_enable(); + return -ENOENT; + } preempt_enable(); -- 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/
