From 41b740b6e8a994e5830daa5e15785522874f7456 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Tue, 10 Aug 2021 21:46:58 -0700 Subject: [PATCH] perf record: Add --synth option Add an option to control the synthesizing behavior. --synth Fine-tune event synthesis: default=all This can be useful when we know it doesn't need some synthesis like in a specific usecase and/or when using pipe: $ perf record -a --all-cgroups --synth cgroup -o- sleep 1 | \ > perf report -i- -s cgroup Committer notes: Added a clarification to the man page entry for --synth that this is about pre-existing threads. Signed-off-by: Namhyung Kim Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Andi Kleen Cc: Ian Rogers Cc: Ingo Molnar Cc: Jin Yao Cc: Peter Zijlstra Cc: Stephane Eranian Link: https //lore.kernel.org/r/20210811044658.1313391-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-record.txt | 16 +++++++++++ tools/perf/builtin-record.c | 48 ++++++++++++++++++++++++++------ tools/perf/util/record.h | 1 + tools/perf/util/synthetic-events.c | 28 +++++++++++++++++++ tools/perf/util/synthetic-events.h | 12 ++++++++ 5 files changed, 96 insertions(+), 9 deletions(-) diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index f1079ee..2d7df87 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -596,6 +596,22 @@ options. 'perf record --dry-run -e' can act as a BPF script compiler if llvm.dump-obj in config file is set to true. +--synth=TYPE:: +Collect and synthesize given type of events (comma separated). Note that +this option controls the synthesis from the /proc filesystem which represent +task status for pre-existing threads. + +Kernel (and some other) events are recorded regardless of the +choice in this option. For example, --synth=no would have MMAP events for +kernel and modules. + +Available types are: + 'task' - synthesize FORK and COMM events for each task + 'mmap' - synthesize MMAP events for each process (implies 'task') + 'cgroup' - synthesize CGROUP events for each cgroup + 'all' - synthesize all events (default) + 'no' - do not synthesize any of the above events + --tail-synthesize:: Instead of collecting non-sample events (for example, fork, comm, mmap) at the beginning of record, collect them during finalizing an output file. diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 0263e383..41bb884 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1255,6 +1255,7 @@ static int record__synthesize_workload(struct record *rec, bool tail) { int err; struct perf_thread_map *thread_map; + bool needs_mmap = rec->opts.synth & PERF_SYNTH_MMAP; if (rec->opts.tail_synthesize != tail) return 0; @@ -1266,7 +1267,7 @@ static int record__synthesize_workload(struct record *rec, bool tail) err = perf_event__synthesize_thread_map(&rec->tool, thread_map, process_synthesized_event, &rec->session->machines.host, - true, + needs_mmap, rec->opts.sample_address); perf_thread_map__put(thread_map); return err; @@ -1471,20 +1472,26 @@ static int record__synthesize(struct record *rec, bool tail) if (err < 0) pr_warning("Couldn't synthesize bpf events.\n"); - err = perf_event__synthesize_cgroups(tool, process_synthesized_event, - machine); - if (err < 0) - pr_warning("Couldn't synthesize cgroup events.\n"); + if (rec->opts.synth & PERF_SYNTH_CGROUP) { + err = perf_event__synthesize_cgroups(tool, process_synthesized_event, + machine); + if (err < 0) + pr_warning("Couldn't synthesize cgroup events.\n"); + } if (rec->opts.nr_threads_synthesize > 1) { perf_set_multithreaded(); f = process_locked_synthesized_event; } - err = __machine__synthesize_threads(machine, tool, &opts->target, - rec->evlist->core.threads, - f, true, opts->sample_address, - rec->opts.nr_threads_synthesize); + if (rec->opts.synth & PERF_SYNTH_TASK) { + bool needs_mmap = rec->opts.synth & PERF_SYNTH_MMAP; + + err = __machine__synthesize_threads(machine, tool, &opts->target, + rec->evlist->core.threads, + f, needs_mmap, opts->sample_address, + rec->opts.nr_threads_synthesize); + } if (rec->opts.nr_threads_synthesize > 1) perf_set_singlethreaded(); @@ -2393,6 +2400,26 @@ static int process_timestamp_boundary(struct perf_tool *tool, return 0; } +static int parse_record_synth_option(const struct option *opt, + const char *str, + int unset __maybe_unused) +{ + struct record_opts *opts = opt->value; + char *p = strdup(str); + + if (p == NULL) + return -1; + + opts->synth = parse_synth_opt(p); + free(p); + + if (opts->synth < 0) { + pr_err("Invalid synth option: %s\n", str); + return -1; + } + return 0; +} + /* * XXX Ideally would be local to cmd_record() and passed to a record__new * because we need to have access to it in record__exit, that is called @@ -2418,6 +2445,7 @@ static struct record record = { .nr_threads_synthesize = 1, .ctl_fd = -1, .ctl_fd_ack = -1, + .synth = PERF_SYNTH_ALL, }, .tool = { .sample = process_sample_event, @@ -2633,6 +2661,8 @@ static struct option __record_options[] = { "\t\t\t Optionally send control command completion ('ack\\n') to ack-fd descriptor.\n" "\t\t\t Alternatively, ctl-fifo / ack-fifo will be opened and used as ctl-fd / ack-fd.", parse_control_option), + OPT_CALLBACK(0, "synth", &record.opts, "no|all|task|mmap|cgroup", + "Fine-tune event synthesis: default=all", parse_record_synth_option), OPT_END() }; diff --git a/tools/perf/util/record.h b/tools/perf/util/record.h index 68f471d..ef6c271 100644 --- a/tools/perf/util/record.h +++ b/tools/perf/util/record.h @@ -77,6 +77,7 @@ struct record_opts { int ctl_fd; int ctl_fd_ack; bool ctl_fd_close; + int synth; }; extern const char * const *record_usage; diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c index a7a2825..1989821 100644 --- a/tools/perf/util/synthetic-events.c +++ b/tools/perf/util/synthetic-events.c @@ -2237,3 +2237,31 @@ int perf_event__synthesize_for_pipe(struct perf_tool *tool, return ret; } + +int parse_synth_opt(char *synth) +{ + char *p, *q; + int ret = 0; + + if (synth == NULL) + return -1; + + for (q = synth; (p = strsep(&q, ",")); p = q) { + if (!strcasecmp(p, "no") || !strcasecmp(p, "none")) + return 0; + + if (!strcasecmp(p, "all")) + return PERF_SYNTH_ALL; + + if (!strcasecmp(p, "task")) + ret |= PERF_SYNTH_TASK; + else if (!strcasecmp(p, "mmap")) + ret |= PERF_SYNTH_TASK | PERF_SYNTH_MMAP; + else if (!strcasecmp(p, "cgroup")) + ret |= PERF_SYNTH_CGROUP; + else + return -1; + } + + return ret; +} diff --git a/tools/perf/util/synthetic-events.h b/tools/perf/util/synthetic-events.h index 44f72d5..c931433 100644 --- a/tools/perf/util/synthetic-events.h +++ b/tools/perf/util/synthetic-events.h @@ -27,6 +27,18 @@ struct target; union perf_event; +enum perf_record_synth { + PERF_SYNTH_TASK = 1 << 0, + PERF_SYNTH_MMAP = 1 << 1, + PERF_SYNTH_CGROUP = 1 << 2, + + /* last element */ + PERF_SYNTH_MAX = 1 << 3, +}; +#define PERF_SYNTH_ALL (PERF_SYNTH_MAX - 1) + +int parse_synth_opt(char *str); + typedef int (*perf_event__handler_t)(struct perf_tool *tool, union perf_event *event, struct perf_sample *sample, struct machine *machine); -- 2.7.4