[PATCH 1/2] arm: perf: Fix ARCH=arm build with GCC in armv8pmu_write_evtype()

From: James Clark
Date: Fri Dec 15 2023 - 10:01:30 EST


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 changing the if to #if.

Fixes: 3115ee021bfb ("arm64: perf: Include threshold control fields in PMEVTYPER mask")
Reported-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
Closes: https://lore.kernel.org/linux-arm-kernel/20231215120817.h2f3akgv72zhrtqo@xxxxxxxxxxxxxx/
Signed-off-by: James Clark <james.clark@xxxxxxx>
---
drivers/perf/arm_pmuv3.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/perf/arm_pmuv3.c b/drivers/perf/arm_pmuv3.c
index 23fa6c5da82c..3ed2086cefc3 100644
--- a/drivers/perf/arm_pmuv3.c
+++ b/drivers/perf/arm_pmuv3.c
@@ -631,8 +631,9 @@ static void armv8pmu_write_evtype(int idx, unsigned long val)
ARMV8_PMU_EXCLUDE_EL0 |
ARMV8_PMU_EXCLUDE_EL1;

- if (IS_ENABLED(CONFIG_ARM64))
- mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
+#if IS_ENABLED(CONFIG_ARM64)
+ mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
+#endif

val &= mask;
write_pmevtypern(counter, val);
--
2.34.1