[PATCH] perf_event: initialize data.period in perf_swevent_hrtimer()

[Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>]

In current code in perf_swevent_hrtimer(), data.period is not initialized,
The result is obvious wrong:

# ./perf record -f -e cpu-clock make
# ./perf report
# Samples: 1740
#
# Overhead   Command                                   ...... 
# ........  ........  ..........................................
#
   1025422183050275328.00%        sh  libc-2.9.90.so ...        
   1025422183050275328.00%      perl  libperl.so     ...        
   1025422168240043264.00%      perl  [kernel]       ...         
   1025422030011210752.00%      perl  [kernel]       ...

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
---
 kernel/perf_event.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 0b9ca2d..040ee51 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -4010,6 +4010,7 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
 	event->pmu->read(event);
 
 	data.addr = 0;
+	data.period = event->hw.last_period;
 	regs = get_irq_regs();
 	/*
 	 * In case we exclude kernel IPs or are somehow not in interrupt
-- 
1.6.1.2