[PATCH 1/2] drivers/perf: thunderx2_pmu: Change data in size tx2_uncore_event_update()

John Garry john.garry at huawei.com
Wed Aug 25 02:10:55 PDT 2021


A LSL of 32 requires > 32b value to hold the result. However in
tx2_uncore_event_update(), 1UL << 32 currently only works as unsigned
long is 64b on a 64b system.

If we want to compile test for a 32b system, we need unsigned long long,
whose min size is 64b.

Signed-off-by: John Garry <john.garry at huawei.com>
---
 drivers/perf/thunderx2_pmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/perf/thunderx2_pmu.c b/drivers/perf/thunderx2_pmu.c
index fc1a376ee906..05378c0fd8f3 100644
--- a/drivers/perf/thunderx2_pmu.c
+++ b/drivers/perf/thunderx2_pmu.c
@@ -487,7 +487,7 @@ static void tx2_uncore_event_update(struct perf_event *event)
 		new = reg_readl(hwc->event_base);
 		prev = local64_xchg(&hwc->prev_count, new);
 		/* handles rollover of 32 bit counter */
-		delta = (u32)(((1UL << 32) - prev) + new);
+		delta = (u32)(((1ULL << 32) - prev) + new);
 	}
 
 	/* DMC event data_transfers granularity is 16 Bytes, convert it to 64 */
-- 
2.26.2




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