From edf3ce0ed38e2d04a817984e4ea7f05b18102926 Mon Sep 17 00:00:00 2001 From: Kan Liang Date: Mon, 9 Sep 2024 11:42:00 -0700 Subject: [PATCH] perf env: Find correct branch counter info on hybrid No event is printed in the "Branch Counter" column on hybrid machines. For example, $ perf record -e "{cpu_core/branch-instructions/pp,cpu_core/branches/}:S" -j any,counter $ perf report --total-cycles # Branch counter abbr list: # cpu_core/branch-instructions/pp = A # cpu_core/branches/ = B # '-' No event occurs # '+' Event occurrences may be lost due to branch counter saturated # # Sampled Cycles% Sampled Cycles Avg Cycles% Avg Cycles Branch Counter # ............... .............. ........... .......... .............. 44.54% 727.1K 0.00% 1 |+ |+ | 36.31% 592.7K 0.00% 2 |+ |+ | 17.83% 291.1K 0.00% 1 |+ |+ | The branch counter information (br_cntr_width and br_cntr_nr) in the perf_env is retrieved from the CPU_PMU_CAPS. However, the CPU_PMU_CAPS is not available on hybrid machines. Without the width information, the number of occurrences of an event cannot be calculated. For a hybrid machine, the caps information should be retrieved from the PMU_CAPS, and stored in the perf_env->pmu_caps. Add a perf_env__find_br_cntr_info() to return the correct branch counter information from the corresponding fields. Committer notes: While testing I couldn't s ee those "Branch counter" columns enabled by pressing 'B' on the TUI, after reporting it to the list Kan explained the situation: For a hybrid client, the "Branch Counter" feature is only supported starting from the just released Lunar Lake. Perf falls back to only "ANY" on your Raptor Lake. The "The branch counter is not available" message is expected. Here is the 'perf evlist' result from my Lunar Lake machine, # perf evlist -v cpu_core/branch-instructions/pp: type: 4 (cpu_core), size: 136, config: 0xc4 (branch-instructions), { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|READ|PERIOD|BRANCH_STACK|IDENTIFIER, read_format: ID|GROUP|LOST, disabled: 1, freq: 1, enable_on_exec: 1, precise_ip: 2, sample_id_all: 1, exclude_guest: 1, branch_sample_type: ANY|COUNTERS # Fixes: 6f9d8d1de2c61288 ("perf script: Add branch counters") Reviewed-by: Ian Rogers Signed-off-by: Kan Liang Cc: Adrian Hunter Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Link: https://lore.kernel.org/r/20240909184201.553519-1-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-script.c | 5 +++-- tools/perf/util/annotate.c | 5 +++-- tools/perf/util/env.c | 15 +++++++++++++++ tools/perf/util/env.h | 3 +++ tools/perf/util/session.c | 6 ++++-- 5 files changed, 28 insertions(+), 6 deletions(-) diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c index dbe792b52c5c..a644787fa9e1 100644 --- a/tools/perf/builtin-script.c +++ b/tools/perf/builtin-script.c @@ -1241,10 +1241,11 @@ static int ip__fprintf_jump(uint64_t ip, struct branch_entry *en, } if (PRINT_FIELD(BRCNTR)) { - unsigned int width = evsel__env(evsel)->br_cntr_width; - unsigned int i = 0, j, num, mask = (1L << width) - 1; struct evsel *pos = evsel__leader(evsel); + unsigned int i = 0, j, num, mask, width; + perf_env__find_br_cntr_info(evsel__env(evsel), NULL, &width); + mask = (1L << width) - 1; printed += fprintf(fp, "br_cntr: "); evlist__for_each_entry_from(evsel->evlist, pos) { if (!(pos->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS)) diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c index 1a347a711dcf..37ce43c4eb8f 100644 --- a/tools/perf/util/annotate.c +++ b/tools/perf/util/annotate.c @@ -333,14 +333,15 @@ static int symbol__account_br_cntr(struct annotated_branch *branch, { unsigned int br_cntr_nr = evsel__leader(evsel)->br_cntr_nr; unsigned int base = evsel__leader(evsel)->br_cntr_idx; - unsigned int width = evsel__env(evsel)->br_cntr_width; unsigned int off = offset * evsel->evlist->nr_br_cntr; - unsigned int i, mask = (1L << width) - 1; u64 *branch_br_cntr = branch->br_cntr; + unsigned int i, mask, width; if (!br_cntr || !branch_br_cntr) return 0; + perf_env__find_br_cntr_info(evsel__env(evsel), NULL, &width); + mask = (1L << width) - 1; for (i = 0; i < br_cntr_nr; i++) { u64 cntr = (br_cntr >> i * width) & mask; diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c index a459374d0a1a..1edbccfc3281 100644 --- a/tools/perf/util/env.c +++ b/tools/perf/util/env.c @@ -624,3 +624,18 @@ out: free(cap_eq); return NULL; } + +void perf_env__find_br_cntr_info(struct perf_env *env, + unsigned int *nr, + unsigned int *width) +{ + if (nr) { + *nr = env->cpu_pmu_caps ? env->br_cntr_nr : + env->pmu_caps->br_cntr_nr; + } + + if (width) { + *width = env->cpu_pmu_caps ? env->br_cntr_width : + env->pmu_caps->br_cntr_width; + } +} diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h index 2a2c37cc40b7..51b36c36019b 100644 --- a/tools/perf/util/env.h +++ b/tools/perf/util/env.h @@ -192,4 +192,7 @@ char *perf_env__find_pmu_cap(struct perf_env *env, const char *pmu_name, const char *cap); bool perf_env__has_pmu_mapping(struct perf_env *env, const char *pmu_name); +void perf_env__find_br_cntr_info(struct perf_env *env, + unsigned int *nr, + unsigned int *width); #endif /* __PERF_ENV_H */ diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index b492300ec959..dbaf07bf6c5f 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -856,7 +856,6 @@ static void branch_stack__printf(struct perf_sample *sample, struct branch_entry *entries = perf_sample__branch_entries(sample); bool callstack = evsel__has_branch_callstack(evsel); u64 *branch_stack_cntr = sample->branch_stack_cntr; - struct perf_env *env = evsel__env(evsel); uint64_t i; if (!callstack) { @@ -900,8 +899,11 @@ static void branch_stack__printf(struct perf_sample *sample, } if (branch_stack_cntr) { + unsigned int br_cntr_width, br_cntr_nr; + + perf_env__find_br_cntr_info(evsel__env(evsel), &br_cntr_nr, &br_cntr_width); printf("... branch stack counters: nr:%" PRIu64 " (counter width: %u max counter nr:%u)\n", - sample->branch_stack->nr, env->br_cntr_width, env->br_cntr_nr); + sample->branch_stack->nr, br_cntr_width, br_cntr_nr); for (i = 0; i < sample->branch_stack->nr; i++) printf("..... %2"PRIu64": %016" PRIx64 "\n", i, branch_stack_cntr[i]); }