smp: Implement kick_all_cpus_sync()

Will replace the misnomed cpu_idle_wait() function which is copied a gazillion times all over arch/*

Thomas Gleixner committed 14 years ago

Commit f37f4351 parent 9cd75e12 files · +27 −0Browse files

Unified · Split

2 files

@@ -81,6 +81,8 @@ void __smp_call_function_single(int cpuid, struct call_single_data *data, · 80 unmodified lines
81	81	int smp_call_function_any(const struct cpumask *mask,
82	82	smp_call_func_t func, void *info, int wait);
83	83
	84	+void kick_all_cpus_sync(void);
	85	+
84	86	/*
85	87	* Generic and arch helpers
86	88	*/
@@ -192,6 +194,8 @@ smp_call_function_any(const struct cpumask *mask, smp_call_func_t func, · 105 unmodified lines
192	194	return smp_call_function_single(0, func, info, wait);
193	195	}
194	196
	197	+static inline void kick_all_cpus_sync(void) { }
	198	+
195	199	#endif /* !SMP */
196	200
197	201	/*

@@ -795,3 +795,26 @@ void on_each_cpu_cond(bool (cond_func)(int cpu, void info), · 794 unmodified lines
795	795	}
796	796	}
797	797	EXPORT_SYMBOL(on_each_cpu_cond);
	798	+
	799	+static void do_nothing(void *unused)
	800	+{
	801	+}
	802	+
	803	+/**
	804	+ * kick_all_cpus_sync - Force all cpus out of idle
	805	+ *
	806	+ * Used to synchronize the update of pm_idle function pointer. It's
	807	+ * called after the pointer is updated and returns after the dummy
	808	+ * callback function has been executed on all cpus. The execution of
	809	+ * the function can only happen on the remote cpus after they have
	810	+ * left the idle function which had been called via pm_idle function
	811	+ * pointer. So it's guaranteed that nothing uses the previous pointer
	812	+ * anymore.
	813	+ */
	814	+void kick_all_cpus_sync(void)
	815	+{
	816	+ /* Make sure the change is visible before we kick the cpus */
	817	+ smp_mb();
	818	+ smp_call_function(do_nothing, NULL, 1);
	819	+}
	820	+EXPORT_SYMBOL_GPL(kick_all_cpus_sync);