From 1f2b7fbb04f53540090ac7d320194654f142443f Mon Sep 17 00:00:00 2001 From: Kan Liang Date: Tue, 13 Aug 2024 09:02:03 -0700 Subject: perf annotate: Save branch counters for each block When annotating a basic block, it's useful to display the occurrences of other events in the block. The branch counter feature is only available for newer Intel platforms. So a dedicated option to display the branch counters is not introduced. Reuse the existing --total-cycles option, which triggers the annotation of a basic block and displays the cycle-related annotation. When the branch counters information is available, the branch counters are automatically appended after all the cycle-related annotation. Accounting the branch counters as well when accounting the cycles in hist__account_cycles(). In 'struct annotated_branch', introduce a br_cntr array to save the accumulation of each branch counter. In a sample, all the branch counters for a branch are saved in a u64 space. Because the saturation of a branch counter is small, e.g., for Intel Sierra Forest, the saturation is only 3. Add ANNOTATION__BR_CNTR_SATURATED_FLAG to indicate if a branch counter once saturated. That can be used to indicate a potential event lost because of the saturation. Reviewed-by: Andi Kleen Signed-off-by: Kan Liang Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20240813160208.2493643-5-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-annotate.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'tools/perf/builtin-annotate.c') diff --git a/tools/perf/builtin-annotate.c b/tools/perf/builtin-annotate.c index d6f6ba5a569d..9b4a8a379b5b 100644 --- a/tools/perf/builtin-annotate.c +++ b/tools/perf/builtin-annotate.c @@ -221,7 +221,8 @@ static int process_branch_callback(struct evsel *evsel, if (a.map != NULL) dso__set_hit(map__dso(a.map)); - hist__account_cycles(sample->branch_stack, al, sample, false, NULL); + hist__account_cycles(sample->branch_stack, al, sample, false, + NULL, evsel); ret = hist_entry_iter__add(&iter, &a, PERF_MAX_STACK_DEPTH, ann); out: -- cgit v1.2.3-59-g8ed1b