From 9754353d0ab123d71bf572a483ecc8b330ef36a3 Mon Sep 17 00:00:00 2001 From: Haixin Yu Date: Mon, 24 Jul 2023 13:06:54 +0800 Subject: [PATCH] perf pmu arm64: Fix reading the PMU cpu slots in sysfs Commit f8ad6018ce3c065a ("perf pmu: Remove duplication around EVENT_SOURCE_DEVICE_PATH") uses sysfs__read_ull() to read a full sysfs path, which will never succeeds as it already comes with the sysfs mount point in it, which sysfs__read_ull() will add again. Fix it by reading the file using filename__read_ull(), that will not add the sysfs mount point. Fixes: f8ad6018ce3c065a ("perf pmu: Remove duplication around EVENT_SOURCE_DEVICE_PATH") Signed-off-by: Haixin Yu Tested-by: Jing Zhang Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Mark Rutland Cc: Mike Leach Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/ZL4G7rWXkfv-Ectq@B-Q60VQ05P-2326.local Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/arch/arm64/util/pmu.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/tools/perf/arch/arm64/util/pmu.c b/tools/perf/arch/arm64/util/pmu.c index 561de0c..512a8f1 100644 --- a/tools/perf/arch/arm64/util/pmu.c +++ b/tools/perf/arch/arm64/util/pmu.c @@ -54,10 +54,11 @@ double perf_pmu__cpu_slots_per_cycle(void) perf_pmu__pathname_scnprintf(path, sizeof(path), pmu->name, "caps/slots"); /* - * The value of slots is not greater than 32 bits, but sysfs__read_int - * can't read value with 0x prefix, so use sysfs__read_ull instead. + * The value of slots is not greater than 32 bits, but + * filename__read_int can't read value with 0x prefix, + * so use filename__read_ull instead. */ - sysfs__read_ull(path, &slots); + filename__read_ull(path, &slots); } return slots ? (double)slots : NAN; -- 2.7.4