perf: Rework and fix the arch CPU-hotplug hooks
Remove the hw_perf_event_*() hotplug hooks in favour of per PMU hotplug
notifiers. This has the advantage of reducing the static weak interface
as well as exposing all hotplug actions to the PMU.
Use this to fix x86 hotplug usage where we did things in ONLINE which
should have been done in UP_PREPARE or STARTING.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
LKML-Reference: <20100305154128.736225361@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 6f8cd7d..80acbf3 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -936,5 +936,21 @@
#define perf_output_put(handle, x) \
perf_output_copy((handle), &(x), sizeof(x))
+/*
+ * This has to have a higher priority than migration_notifier in sched.c.
+ */
+#define perf_cpu_notifier(fn) \
+do { \
+ static struct notifier_block fn##_nb __cpuinitdata = \
+ { .notifier_call = fn, .priority = 20 }; \
+ fn(&fn##_nb, (unsigned long)CPU_UP_PREPARE, \
+ (void *)(unsigned long)smp_processor_id()); \
+ fn(&fn##_nb, (unsigned long)CPU_STARTING, \
+ (void *)(unsigned long)smp_processor_id()); \
+ fn(&fn##_nb, (unsigned long)CPU_ONLINE, \
+ (void *)(unsigned long)smp_processor_id()); \
+ register_cpu_notifier(&fn##_nb); \
+} while (0)
+
#endif /* __KERNEL__ */
#endif /* _LINUX_PERF_EVENT_H */