From ba993e5ada1ddce7a71140dc85ef65bc2cd981bc Mon Sep 17 00:00:00 2001 From: James Clark Date: Tue, 29 Oct 2024 14:37:33 +0000 Subject: [PATCH] perf arm-spe: Use old behavior when opening old SPE files Since the linked commit, we stopped interpreting data source if the perf.data file doesn't have the new metadata version. This means that perf c2c will show no samples in this case. Keep the old behavior so old files can be opened, but also still show the new warning that updating might improve the decoding. Also re-write the warning to be more concise and specific to a user. Fixes: ba5e7169e548 ("perf arm-spe: Use metadata to decide the data source feature") Signed-off-by: James Clark Reviewed-by: Leo Yan Cc: Julio.Suarez@arm.com Cc: Kiel.Friedt@arm.com Cc: Ryan.Roberts@arm.com Cc: Will Deacon Cc: Mike Leach Cc: linux-arm-kernel@lists.infradead.org Cc: Besar Wicaksono Cc: John Garry Link: https://lore.kernel.org/r/20241029143734.291638-1-james.clark@linaro.org Signed-off-by: Namhyung Kim --- tools/perf/util/arm-spe.c | 50 +++++++++++++++++++-------------------- 1 file changed, 24 insertions(+), 26 deletions(-) diff --git a/tools/perf/util/arm-spe.c b/tools/perf/util/arm-spe.c index a291a412f6a1..dbf13f47879c 100644 --- a/tools/perf/util/arm-spe.c +++ b/tools/perf/util/arm-spe.c @@ -562,37 +562,35 @@ static bool arm_spe__is_common_ds_encoding(struct arm_spe_queue *speq) u64 *metadata = NULL; u64 midr = 0; - /* - * Metadata version 1 doesn't contain any info for MIDR. - * Simply return false in this case. - */ + /* Metadata version 1 assumes all CPUs are the same (old behavior) */ if (spe->metadata_ver == 1) { - pr_warning_once("The data file contains metadata version 1, " - "which is absent the info for data source. " - "Please upgrade the tool to record data.\n"); - return false; - } - - /* CPU ID is -1 for per-thread mode */ - if (speq->cpu < 0) { - /* - * On the heterogeneous system, due to CPU ID is -1, - * cannot confirm the data source packet is supported. - */ - if (!spe->is_homogeneous) - return false; + const char *cpuid; - /* In homogeneous system, simply use CPU0's metadata */ - if (spe->metadata) - metadata = spe->metadata[0]; + pr_warning_once("Old SPE metadata, re-record to improve decode accuracy\n"); + cpuid = perf_env__cpuid(spe->session->evlist->env); + midr = strtol(cpuid, NULL, 16); } else { - metadata = arm_spe__get_metadata_by_cpu(spe, speq->cpu); - } + /* CPU ID is -1 for per-thread mode */ + if (speq->cpu < 0) { + /* + * On the heterogeneous system, due to CPU ID is -1, + * cannot confirm the data source packet is supported. + */ + if (!spe->is_homogeneous) + return false; + + /* In homogeneous system, simply use CPU0's metadata */ + if (spe->metadata) + metadata = spe->metadata[0]; + } else { + metadata = arm_spe__get_metadata_by_cpu(spe, speq->cpu); + } - if (!metadata) - return false; + if (!metadata) + return false; - midr = metadata[ARM_SPE_CPU_MIDR]; + midr = metadata[ARM_SPE_CPU_MIDR]; + } is_in_cpu_list = is_midr_in_range_list(midr, common_ds_encoding_cpus); if (is_in_cpu_list) -- 2.50.1