From e5af139715aaf17f25bc50638a7ca67973fce2af Mon Sep 17 00:00:00 2001 From: James Clark Date: Wed, 8 Mar 2023 09:48:43 +0000 Subject: [PATCH] perf cs-etm: Avoid printing warning in cs_etm_is_ete() check When checking for the presence of ETE, a register is read that may not be present on older kernels or if ETE isn't available. cs_etm_get_ro() will print a warning if it doesn't exist, so check for the existence first before accessing it. Reviewed-by: Leo Yan Signed-off-by: James Clark Cc: Al Grant Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: John Garry Cc: Mark Rutland Cc: Mathieu Poirier Cc: Mike Leach Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Suzuki Poulouse Cc: Will Deacon Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20230308094843.287093-1-james.clark@arm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/arch/arm/util/cs-etm.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/tools/perf/arch/arm/util/cs-etm.c b/tools/perf/arch/arm/util/cs-etm.c index 59b50dd..86b61ad 100644 --- a/tools/perf/arch/arm/util/cs-etm.c +++ b/tools/perf/arch/arm/util/cs-etm.c @@ -659,8 +659,12 @@ static bool cs_etm_is_ete(struct auxtrace_record *itr, int cpu) { struct cs_etm_recording *ptr = container_of(itr, struct cs_etm_recording, itr); struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu; - int trcdevarch = cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCDEVARCH]); + int trcdevarch; + if (!cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCDEVARCH])) + return false; + + trcdevarch = cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCDEVARCH]); /* * ETE if ARCHVER is 5 (ARCHVER is 4 for ETM) and ARCHPART is 0xA13. * See ETM_DEVARCH_ETE_ARCH in coresight-etm4x.h -- 2.7.4