It makes the registration cheaper and simpler for the smpboot per-cpu kthread users that don't need to always update the cpumask after threads creation.
Cc: Andrew Morton <[email protected]> Cc: Chris Metcalf <[email protected]> Cc: Don Zickus <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ulrich Obergfell <[email protected]> Signed-off-by: Frederic Weisbecker <[email protected]> --- include/linux/smpboot.h | 11 ++++++++++- kernel/smpboot.c | 9 ++++++--- kernel/watchdog.c | 9 +++------ 3 files changed, 19 insertions(+), 10 deletions(-) diff --git a/include/linux/smpboot.h b/include/linux/smpboot.h index da3c593..e6109a6 100644 --- a/include/linux/smpboot.h +++ b/include/linux/smpboot.h @@ -48,7 +48,16 @@ struct smp_hotplug_thread { const char *thread_comm; }; -int smpboot_register_percpu_thread(struct smp_hotplug_thread *plug_thread); +int smpboot_register_percpu_thread_cpumask(struct smp_hotplug_thread *plug_thread, + const struct cpumask *cpumask); + +static inline int +smpboot_register_percpu_thread(struct smp_hotplug_thread *plug_thread) +{ + return smpboot_register_percpu_thread_cpumask(plug_thread, + cpu_possible_mask); +} + void smpboot_unregister_percpu_thread(struct smp_hotplug_thread *plug_thread); int smpboot_update_cpumask_percpu_thread(struct smp_hotplug_thread *plug_thread, const struct cpumask *); diff --git a/kernel/smpboot.c b/kernel/smpboot.c index 60aa858..699846d 100644 --- a/kernel/smpboot.c +++ b/kernel/smpboot.c @@ -275,17 +275,19 @@ static void smpboot_destroy_threads(struct smp_hotplug_thread *ht) /** * smpboot_register_percpu_thread - Register a per_cpu thread related to hotplug * @plug_thread: Hotplug thread descriptor + * @cpumask: The cpumask where threads run * * Creates and starts the threads on all online cpus. */ -int smpboot_register_percpu_thread(struct smp_hotplug_thread *plug_thread) +int smpboot_register_percpu_thread_cpumask(struct smp_hotplug_thread *plug_thread, + const struct cpumask *cpumask) { unsigned int cpu; int ret = 0; if (!alloc_cpumask_var(&plug_thread->cpumask, GFP_KERNEL)) return -ENOMEM; - cpumask_copy(plug_thread->cpumask, cpu_possible_mask); + cpumask_copy(plug_thread->cpumask, cpumask); get_online_cpus(); mutex_lock(&smpboot_threads_lock); @@ -296,7 +298,8 @@ int smpboot_register_percpu_thread(struct smp_hotplug_thread *plug_thread) free_cpumask_var(plug_thread->cpumask); goto out; } - smpboot_unpark_thread(plug_thread, cpu); + if (cpumask_test_cpu(cpu, cpumask)) + smpboot_unpark_thread(plug_thread, cpu); } list_add(&plug_thread->list, &hotplug_threads); out: diff --git a/kernel/watchdog.c b/kernel/watchdog.c index a6ffa43..e5bb86f 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -713,15 +713,12 @@ static int watchdog_enable_all_cpus(void) int err = 0; if (!watchdog_running) { - err = smpboot_register_percpu_thread(&watchdog_threads); + err = smpboot_register_percpu_thread_cpumask(&watchdog_threads, + &watchdog_cpumask); if (err) pr_err("Failed to create watchdog threads, disabled\n"); - else { - if (smpboot_update_cpumask_percpu_thread( - &watchdog_threads, &watchdog_cpumask)) - pr_err("Failed to set cpumask for watchdog threads\n"); + else watchdog_running = 1; - } } else { /* * Enable/disable the lockup detectors or -- 2.1.4 -- 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/
