cpuset: Make cpuset hotplug synchronous (1599a185) · Commits · 戴 / test

include/linux/cpuset.h

+0 −6

Original line number	Diff line number	Diff line
		@@ -52,9 +52,7 @@ static inline void cpuset_dec(void)

		extern int cpuset_init(void);
		extern void cpuset_init_smp(void);
		extern void cpuset_force_rebuild(void);
		extern void cpuset_update_active_cpus(void);
		extern void cpuset_wait_for_hotplug(void);
		extern void cpuset_cpus_allowed(struct task_struct p, struct cpumask mask);
		extern void cpuset_cpus_allowed_fallback(struct task_struct *p);
		extern nodemask_t cpuset_mems_allowed(struct task_struct *p);
		@@ -167,15 +165,11 @@ static inline bool cpusets_enabled(void) { return false; }
		static inline int cpuset_init(void) { return 0; }
		static inline void cpuset_init_smp(void) {}

		static inline void cpuset_force_rebuild(void) { }

		static inline void cpuset_update_active_cpus(void)
		{
		partition_sched_domains(1, NULL, NULL);
		}

		static inline void cpuset_wait_for_hotplug(void) { }

		static inline void cpuset_cpus_allowed(struct task_struct *p,
		struct cpumask *mask)
		{

kernel/cgroup/cpuset.c

+20 −21

Original line number	Diff line number	Diff line
		@@ -2277,15 +2277,8 @@ retry:
		mutex_unlock(&cpuset_mutex);
		}

		static bool force_rebuild;

		void cpuset_force_rebuild(void)
		{
		force_rebuild = true;
		}

		/**
		* cpuset_hotplug_workfn - handle CPU/memory hotunplug for a cpuset
		* cpuset_hotplug - handle CPU/memory hotunplug for a cpuset
		*
		* This function is called after either CPU or memory configuration has
		* changed and updates cpuset accordingly. The top_cpuset is always
		@@ -2300,7 +2293,7 @@ void cpuset_force_rebuild(void)
		* Note that CPU offlining during suspend is ignored. We don't modify
		* cpusets across suspend/resume cycles at all.
		*/
		static void cpuset_hotplug_workfn(struct work_struct *work)
		static void cpuset_hotplug(bool use_cpu_hp_lock)
		{
		static cpumask_t new_cpus;
		static nodemask_t new_mems;
		@@ -2358,25 +2351,31 @@ static void cpuset_hotplug_workfn(struct work_struct *work)
		}

		/* rebuild sched domains if cpus_allowed has changed */
		if (cpus_updated \|\| force_rebuild) {
		force_rebuild = false;
		if (cpus_updated) {
		if (use_cpu_hp_lock)
		rebuild_sched_domains();
		else {
		/* Acquiring cpu_hotplug_lock is not required.
		* When cpuset_hotplug() is called in hotplug path,
		* cpu_hotplug_lock is held by the hotplug context
		* which is waiting for cpuhp_thread_fun to indicate
		* completion of callback.
		*/
		mutex_lock(&cpuset_mutex);
		rebuild_sched_domains_cpuslocked();
		mutex_unlock(&cpuset_mutex);
		}
		}
		}

		void cpuset_update_active_cpus(void)
		static void cpuset_hotplug_workfn(struct work_struct *work)
		{
		/*
		* We're inside cpu hotplug critical region which usually nests
		* inside cgroup synchronization. Bounce actual hotplug processing
		* to a work item to avoid reverse locking order.
		*/
		schedule_work(&cpuset_hotplug_work);
		cpuset_hotplug(true);
		}

		void cpuset_wait_for_hotplug(void)
		void cpuset_update_active_cpus(void)
		{
		flush_work(&cpuset_hotplug_work);
		cpuset_hotplug(false);
		}

		/*

kernel/power/process.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -204,8 +204,6 @@ void thaw_processes(void)
		__usermodehelper_set_disable_depth(UMH_FREEZING);
		thaw_workqueues();

		cpuset_wait_for_hotplug();

		read_lock(&tasklist_lock);
		for_each_process_thread(g, p) {
		/* No other threads should have PF_SUSPEND_TASK set */

kernel/sched/core.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -5624,7 +5624,6 @@ static void cpuset_cpu_active(void)
		* restore the original sched domains by considering the
		* cpuset configurations.
		*/
		cpuset_force_rebuild();
		}
		cpuset_update_active_cpus();
		}

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