[PATCH 6/8] perf: optimize __perf_sw_event()

[Peter Zijlstra]

From: Ingo Molnar <mingo@xxxxxxx>

Ingo noticed that the C99 initialisation of the structure resulted in
a memset() and an assignment. Use explicit assignments to avoid the
memset.

perf_prepare_sample() initializes all data entries, except:
  addr, period and raw.

period is set in perf_swevent_overflow, addr is set here, leaving only
raw to be dealt with, so clear that explicitly as well.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
---
 kernel/perf_event.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

Index: linux-2.6/kernel/perf_event.c
===================================================================
--- linux-2.6.orig/kernel/perf_event.c
+++ linux-2.6/kernel/perf_event.c
@@ -3945,9 +3945,10 @@ out:
 void __perf_sw_event(u32 event_id, u64 nr, int nmi,
 			    struct pt_regs *regs, u64 addr)
 {
-	struct perf_sample_data data = {
-		.addr = addr,
-	};
+	struct perf_sample_data data;
+
+	data.addr = addr;
+	data.raw  = NULL;
 
 	do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, nmi,
 				&data, regs);

-- 

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