Merge tag 'cpu-hotplug-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull CPU hotplug notifiers registration fixes from Rafael Wysocki:
 "The purpose of this single series of commits from Srivatsa S Bhat
  (with a small piece from Gautham R Shenoy) touching multiple
  subsystems that use CPU hotplug notifiers is to provide a way to
  register them that will not lead to deadlocks with CPU online/offline
  operations as described in the changelog of commit 93ae4f978ca7f ("CPU
  hotplug: Provide lockless versions of callback registration
  functions").

  The first three commits in the series introduce the API and document
  it and the rest simply goes through the users of CPU hotplug notifiers
  and converts them to using the new method"

* tag 'cpu-hotplug-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (52 commits)
  net/iucv/iucv.c: Fix CPU hotplug callback registration
  net/core/flow.c: Fix CPU hotplug callback registration
  mm, zswap: Fix CPU hotplug callback registration
  mm, vmstat: Fix CPU hotplug callback registration
  profile: Fix CPU hotplug callback registration
  trace, ring-buffer: Fix CPU hotplug callback registration
  xen, balloon: Fix CPU hotplug callback registration
  hwmon, via-cputemp: Fix CPU hotplug callback registration
  hwmon, coretemp: Fix CPU hotplug callback registration
  thermal, x86-pkg-temp: Fix CPU hotplug callback registration
  octeon, watchdog: Fix CPU hotplug callback registration
  oprofile, nmi-timer: Fix CPU hotplug callback registration
  intel-idle: Fix CPU hotplug callback registration
  clocksource, dummy-timer: Fix CPU hotplug callback registration
  drivers/base/topology.c: Fix CPU hotplug callback registration
  acpi-cpufreq: Fix CPU hotplug callback registration
  zsmalloc: Fix CPU hotplug callback registration
  scsi, fcoe: Fix CPU hotplug callback registration
  scsi, bnx2fc: Fix CPU hotplug callback registration
  scsi, bnx2i: Fix CPU hotplug callback registration
  ...

2 files changed, 62 insertions, 1 deletions

diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 03e962e23eaf..81887120395c 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -115,26 +115,46 @@ enum {
 		{ .notifier_call = fn, .priority = pri };	\
 	register_cpu_notifier(&fn##_nb);			\
 }
+
+#define __cpu_notifier(fn, pri) {				\
+	static struct notifier_block fn##_nb =			\
+		{ .notifier_call = fn, .priority = pri };	\
+	__register_cpu_notifier(&fn##_nb);			\
+}
 #else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
 #define cpu_notifier(fn, pri)	do { (void)(fn); } while (0)
+#define __cpu_notifier(fn, pri)	do { (void)(fn); } while (0)
 #endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
+
 #ifdef CONFIG_HOTPLUG_CPU
 extern int register_cpu_notifier(struct notifier_block *nb);
+extern int __register_cpu_notifier(struct notifier_block *nb);
 extern void unregister_cpu_notifier(struct notifier_block *nb);
+extern void __unregister_cpu_notifier(struct notifier_block *nb);
 #else
 
 #ifndef MODULE
 extern int register_cpu_notifier(struct notifier_block *nb);
+extern int __register_cpu_notifier(struct notifier_block *nb);
 #else
 static inline int register_cpu_notifier(struct notifier_block *nb)
 {
 	return 0;
 }
+
+static inline int __register_cpu_notifier(struct notifier_block *nb)
+{
+	return 0;
+}
 #endif
 
 static inline void unregister_cpu_notifier(struct notifier_block *nb)
 {
 }
+
+static inline void __unregister_cpu_notifier(struct notifier_block *nb)
+{
+}
 #endif
 
 int cpu_up(unsigned int cpu);
@@ -142,19 +162,32 @@ void notify_cpu_starting(unsigned int cpu);
 extern void cpu_maps_update_begin(void);
 extern void cpu_maps_update_done(void);
 
+#define cpu_notifier_register_begin	cpu_maps_update_begin
+#define cpu_notifier_register_done	cpu_maps_update_done
+
 #else	/* CONFIG_SMP */
 
 #define cpu_notifier(fn, pri)	do { (void)(fn); } while (0)
+#define __cpu_notifier(fn, pri)	do { (void)(fn); } while (0)
 
 static inline int register_cpu_notifier(struct notifier_block *nb)
 {
 	return 0;
 }
 
+static inline int __register_cpu_notifier(struct notifier_block *nb)
+{
+	return 0;
+}
+
 static inline void unregister_cpu_notifier(struct notifier_block *nb)
 {
 }
 
+static inline void __unregister_cpu_notifier(struct notifier_block *nb)
+{
+}
+
 static inline void cpu_maps_update_begin(void)
 {
 }
@@ -163,6 +196,14 @@ static inline void cpu_maps_update_done(void)
 {
 }
 
+static inline void cpu_notifier_register_begin(void)
+{
+}
+
+static inline void cpu_notifier_register_done(void)
+{
+}
+
 #endif /* CONFIG_SMP */
 extern struct bus_type cpu_subsys;
 
@@ -176,8 +217,11 @@ extern void put_online_cpus(void);
 extern void cpu_hotplug_disable(void);
 extern void cpu_hotplug_enable(void);
 #define hotcpu_notifier(fn, pri)	cpu_notifier(fn, pri)
+#define __hotcpu_notifier(fn, pri)	__cpu_notifier(fn, pri)
 #define register_hotcpu_notifier(nb)	register_cpu_notifier(nb)
+#define __register_hotcpu_notifier(nb)	__register_cpu_notifier(nb)
 #define unregister_hotcpu_notifier(nb)	unregister_cpu_notifier(nb)
+#define __unregister_hotcpu_notifier(nb)	__unregister_cpu_notifier(nb)
 void clear_tasks_mm_cpumask(int cpu);
 int cpu_down(unsigned int cpu);
 
@@ -190,9 +234,12 @@ static inline void cpu_hotplug_done(void) {}
 #define cpu_hotplug_disable()	do { } while (0)
 #define cpu_hotplug_enable()	do { } while (0)
 #define hotcpu_notifier(fn, pri)	do { (void)(fn); } while (0)
+#define __hotcpu_notifier(fn, pri)	do { (void)(fn); } while (0)
 /* These aren't inline functions due to a GCC bug. */
 #define register_hotcpu_notifier(nb)	({ (void)(nb); 0; })
+#define __register_hotcpu_notifier(nb)	({ (void)(nb); 0; })
 #define unregister_hotcpu_notifier(nb)	({ (void)(nb); })
+#define __unregister_hotcpu_notifier(nb)	({ (void)(nb); })
 #endif		/* CONFIG_HOTPLUG_CPU */
 
 #ifdef CONFIG_PM_SLEEP_SMP
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index e56b07f5c9b6..3356abcfff18 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -835,6 +835,8 @@ do {									\
 		{ .notifier_call = fn, .priority = CPU_PRI_PERF };	\
 	unsigned long cpu = smp_processor_id();				\
 	unsigned long flags;						\
+									\
+	cpu_notifier_register_begin();					\
 	fn(&fn##_nb, (unsigned long)CPU_UP_PREPARE,			\
 		(void *)(unsigned long)cpu);				\
 	local_irq_save(flags);						\
@@ -843,9 +845,21 @@ do {									\
 	local_irq_restore(flags);					\
 	fn(&fn##_nb, (unsigned long)CPU_ONLINE,				\
 		(void *)(unsigned long)cpu);				\
-	register_cpu_notifier(&fn##_nb);				\
+	__register_cpu_notifier(&fn##_nb);				\
+	cpu_notifier_register_done();					\
 } while (0)
 
+/*
+ * Bare-bones version of perf_cpu_notifier(), which doesn't invoke the
+ * callback for already online CPUs.
+ */
+#define __perf_cpu_notifier(fn)						\
+do {									\
+	static struct notifier_block fn##_nb =				\
+		{ .notifier_call = fn, .priority = CPU_PRI_PERF };	\
+									\
+	__register_cpu_notifier(&fn##_nb);				\
+} while (0)
 
 struct perf_pmu_events_attr {
 	struct device_attribute attr;