Commit-ID: 4aff1ca6970afbf9cd916c34a9c442c8ccba905e Gitweb: http://git.kernel.org/tip/4aff1ca6970afbf9cd916c34a9c442c8ccba905e Author: Oleg Nesterov <[email protected]> AuthorDate: Sun, 15 Nov 2015 20:33:23 +0100 Committer: Ingo Molnar <[email protected]> CommitDate: Mon, 23 Nov 2015 09:48:19 +0100
stop_machine: Change __stop_cpus() to rely on cpu_stop_queue_work() Change queue_stop_cpus_work() to return true if it queues at least one work, this means that the caller should wait. __stop_cpus() can check the value returned by queue_stop_cpus_work() and avoid done.executed, just like stop_one_cpu() does. Signed-off-by: Oleg Nesterov <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Tejun Heo <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Milos Vyletel <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Prarit Bhargava <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- kernel/stop_machine.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 68b73c4..ed2019a 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -318,12 +318,13 @@ bool stop_one_cpu_nowait(unsigned int cpu, cpu_stop_fn_t fn, void *arg, /* static data for stop_cpus */ static DEFINE_MUTEX(stop_cpus_mutex); -static void queue_stop_cpus_work(const struct cpumask *cpumask, +static bool queue_stop_cpus_work(const struct cpumask *cpumask, cpu_stop_fn_t fn, void *arg, struct cpu_stop_done *done) { struct cpu_stop_work *work; unsigned int cpu; + bool queued = false; /* * Disable preemption while queueing to avoid getting @@ -336,9 +337,12 @@ static void queue_stop_cpus_work(const struct cpumask *cpumask, work->fn = fn; work->arg = arg; work->done = done; - cpu_stop_queue_work(cpu, work); + if (cpu_stop_queue_work(cpu, work)) + queued = true; } lg_global_unlock(&stop_cpus_lock); + + return queued; } static int __stop_cpus(const struct cpumask *cpumask, @@ -347,9 +351,11 @@ static int __stop_cpus(const struct cpumask *cpumask, struct cpu_stop_done done; cpu_stop_init_done(&done, cpumask_weight(cpumask)); - queue_stop_cpus_work(cpumask, fn, arg, &done); + if (!queue_stop_cpus_work(cpumask, fn, arg, &done)) + return -ENOENT; wait_for_completion(&done.completion); - return done.executed ? done.ret : -ENOENT; + WARN_ON(!done.executed); + return done.ret; } /** -- 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/
