[PATCH] perf kvm: Fix RISC-V VM-exit duration accounting

[lirongqing]

From: Li RongQing <lirongqing at baidu.com>

Use kvm_exit as the start event and the following kvm_entry as the
end event for RISC-V VM-exit statistics. Keep decoding scause from
the exit sample.

Before this change, RISC-V measured guest runtime as VM-exit time.

Fixes: da7b1b525e97 ("perf kvm/riscv: Port perf kvm stat to RISC-V")
Signed-off-by: Li RongQing <lirongqing at baidu.com>
---
 tools/perf/util/kvm-stat-arch/kvm-stat-riscv.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/tools/perf/util/kvm-stat-arch/kvm-stat-riscv.c b/tools/perf/util/kvm-stat-arch/kvm-stat-riscv.c
index 967bba2..09c9c7d 100644
--- a/tools/perf/util/kvm-stat-arch/kvm-stat-riscv.c
+++ b/tools/perf/util/kvm-stat-arch/kvm-stat-riscv.c
@@ -31,13 +31,7 @@ static void event_get_key(struct perf_sample *sample,
 }
 
 static bool event_begin(struct perf_sample *sample,
-			struct event_key *key __maybe_unused)
-{
-	return evsel__name_is(sample->evsel, kvm_entry_trace(EM_RISCV));
-}
-
-static bool event_end(struct perf_sample *sample,
-		      struct event_key *key)
+			struct event_key *key)
 {
 	if (evsel__name_is(sample->evsel, kvm_exit_trace(EM_RISCV))) {
 		event_get_key(sample, key);
@@ -46,6 +40,12 @@ static bool event_end(struct perf_sample *sample,
 	return false;
 }
 
+static bool event_end(struct perf_sample *sample,
+		      struct event_key *key __maybe_unused)
+{
+	return evsel__name_is(sample->evsel, kvm_entry_trace(EM_RISCV));
+}
+
 static const struct kvm_events_ops exit_events = {
 	.is_begin_event = event_begin,
 	.is_end_event	= event_end,
-- 
2.9.4