arm: perf: Fix ARCH=arm build with GCC
authorJames Clark <james.clark@arm.com>
Fri, 15 Dec 2023 17:56:48 +0000 (17:56 +0000)
committerWill Deacon <will@kernel.org>
Sun, 17 Dec 2023 12:00:00 +0000 (12:00 +0000)
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>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231215175648.3397170-2-james.clark@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
include/linux/perf/arm_pmuv3.h

index 0f4d62ef3a9a14d70e59eacfd9d3e151ef1eb714..46377e134d67cba65d7f2aa59dc4127af71381de 100644 (file)
  * 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