[PATCH v2 1/1] arm: perf: Fix ARCH=arm build with GCC

James Clark
2023-12-15T17:57:15Z

LLVM ignores everything inside the if statement and doesn't generate
errors, but GCC doesn't ignore it, resulting in the following error:

drivers/perf/arm_pmuv3.c: In function ‘armv8pmu_write_evtype’:
include/linux/bits.h:34:29: error: left shift count >= width of type [-Werror=shift-count-overflow]
34 | (((~UL(0)) - (UL(1) << (l)) + 1) & \

Fix it by using GENMASK_ULL which doesn't overflow on arm32 (even though
the value is never used there).

Fixes: 3115ee021bfb ("arm64: perf: Include threshold control fields in PMEVTYPER mask")
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Closes: https://lore.kernel.org/linux-arm-kernel/20231215120817.h2f3akgv72zhrtqo@pengutronix.de/
Signed-off-by: James Clark <james.clark@arm.com>
---
include/linux/perf/arm_pmuv3.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/perf/arm_pmuv3.h b/include/linux/perf/arm_pmuv3.h
index 0f4d62ef3a9a..46377e134d67 100644
--- a/include/linux/perf/arm_pmuv3.h
+++ b/include/linux/perf/arm_pmuv3.h
@@ -234,8 +234,8 @@
* PMXEVTYPER: Event selection reg
*/
#define ARMV8_PMU_EVTYPE_EVENT GENMASK(15, 0) /* Mask for EVENT bits */
-#define ARMV8_PMU_EVTYPE_TH GENMASK(43, 32)
-#define ARMV8_PMU_EVTYPE_TC GENMASK(63, 61)
+#define ARMV8_PMU_EVTYPE_TH GENMASK_ULL(43, 32) /* arm64 only */
+#define ARMV8_PMU_EVTYPE_TC GENMASK_ULL(63, 61) /* arm64 only */

/*
* Event filters for PMUv3
--
2.34.1