smp: Implement kick_all_cpus_sync() (f37f435f) · Commits · 戴 / test

include/linux/smp.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -81,6 +81,8 @@ void __smp_call_function_single(int cpuid, struct call_single_data *data,
		int smp_call_function_any(const struct cpumask *mask,
		smp_call_func_t func, void *info, int wait);

		void kick_all_cpus_sync(void);

		/*
		* Generic and arch helpers
		*/
		@@ -192,6 +194,8 @@ smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
		return smp_call_function_single(0, func, info, wait);
		}

		static inline void kick_all_cpus_sync(void) { }

		#endif /* !SMP */

		/*

+23 −0

Original line number	Diff line number	Diff line
		@@ -795,3 +795,26 @@ void on_each_cpu_cond(bool (cond_func)(int cpu, void info),
		}
		}
		EXPORT_SYMBOL(on_each_cpu_cond);

		static void do_nothing(void *unused)
		{
		}

		/**
		* kick_all_cpus_sync - Force all cpus out of idle
		*
		* Used to synchronize the update of pm_idle function pointer. It's
		* called after the pointer is updated and returns after the dummy
		* callback function has been executed on all cpus. The execution of
		* the function can only happen on the remote cpus after they have
		* left the idle function which had been called via pm_idle function
		* pointer. So it's guaranteed that nothing uses the previous pointer
		* anymore.
		*/
		void kick_all_cpus_sync(void)
		{
		/* Make sure the change is visible before we kick the cpus */
		smp_mb();
		smp_call_function(do_nothing, NULL, 1);
		}
		EXPORT_SYMBOL_GPL(kick_all_cpus_sync);