perf_counter: Add ioctl for changing the sample period/frequency

Reported-by: Stephane Eranian <eranian@googlemail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 5 insertions, 4 deletions

diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index c046f7d97cfa..45bdd3b95d3e 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -164,10 +164,11 @@ struct perf_counter_hw_event {
 /*
  * Ioctls that can be done on a perf counter fd:
  */
-#define PERF_COUNTER_IOC_ENABLE         _IOW('$', 0, u32)
-#define PERF_COUNTER_IOC_DISABLE        _IOW('$', 1, u32)
-#define PERF_COUNTER_IOC_REFRESH        _IOW('$', 2, u32)
-#define PERF_COUNTER_IOC_RESET          _IOW('$', 3, u32)
+#define PERF_COUNTER_IOC_ENABLE         _IO ('$', 0)
+#define PERF_COUNTER_IOC_DISABLE        _IO ('$', 1)
+#define PERF_COUNTER_IOC_REFRESH        _IO ('$', 2)
+#define PERF_COUNTER_IOC_RESET          _IO ('$', 3)
+#define PERF_COUNTER_IOC_PERIOD         _IOW('$', 4, u64)
 
 enum perf_counter_ioc_flags {
         PERF_IOC_FLAG_GROUP             = 1U << 0,