From a8fcbd269b4340c36dbf99b4453bcbfe128d93fb Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Wed, 2 Sep 2020 13:57:07 +0300 Subject: [PATCH] perf tools: Add FIFO file names as alternative options to --control Enable the --control option to accept file names as an alternative to file descriptors. Example: $ mkfifo perf.control $ mkfifo perf.ack $ cat perf.ack & [1] 6808 $ perf record --control fifo:perf.control,perf.ack -- sleep 300 & [2] 6810 $ echo disable > perf.control $ Events disabled ack $ echo enable > perf.control $ Events enabled ack $ echo disable > perf.control $ Events disabled ack $ kill %2 [ perf record: Woken up 4 times to write data ] $ [ perf record: Captured and wrote 0.018 MB perf.data (7 samples) ] [1]- Done cat perf.ack [2]+ Terminated perf record --control fifo:perf.control,perf.ack -- sleep 300 $ Signed-off-by: Adrian Hunter Acked-by: Alexey Budankov Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Andi Kleen Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/20200902105707.11491-1-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-record.txt | 2 ++ tools/perf/Documentation/perf-stat.txt | 2 ++ tools/perf/builtin-record.c | 34 +++++++++++++++----- tools/perf/builtin-stat.c | 18 +++++++++-- tools/perf/util/evlist.c | 55 ++++++++++++++++++++++++++++++-- tools/perf/util/evlist.h | 2 +- tools/perf/util/record.h | 1 + tools/perf/util/stat.h | 1 + 8 files changed, 101 insertions(+), 14 deletions(-) diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index 34c80aa..c1f4463 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -631,7 +631,9 @@ option. The -e option and this one can be mixed and matched. Events can be grouped using the {} notation. endif::HAVE_LIBPFM[] +--control=fifo:ctl-fifo[,ack-fifo]:: --control=fd:ctl-fd[,ack-fd]:: +ctl-fifo / ack-fifo are opened and used as ctl-fd / ack-fd as follows. Listen on ctl-fd descriptor for command to control measurement ('enable': enable events, 'disable': disable events). Measurements can be started with events disabled using --delay=-1 option. Optionally send control command completion ('ack\n') to ack-fd descriptor diff --git a/tools/perf/Documentation/perf-stat.txt b/tools/perf/Documentation/perf-stat.txt index 224795e..7d18694 100644 --- a/tools/perf/Documentation/perf-stat.txt +++ b/tools/perf/Documentation/perf-stat.txt @@ -180,7 +180,9 @@ with it. --append may be used here. Examples: 3>results perf stat --log-fd 3 -- $cmd 3>>results perf stat --log-fd 3 --append -- $cmd +--control=fifo:ctl-fifo[,ack-fifo]:: --control=fd:ctl-fd[,ack-fd]:: +ctl-fifo / ack-fifo are opened and used as ctl-fd / ack-fd as follows. Listen on ctl-fd descriptor for command to control measurement ('enable': enable events, 'disable': disable events). Measurements can be started with events disabled using --delay=-1 option. Optionally send control command completion ('ack\n') to ack-fd descriptor diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 50591e0..c83aec4 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -2236,7 +2236,17 @@ static int parse_control_option(const struct option *opt, { struct record_opts *opts = opt->value; - return evlist__parse_control(str, &opts->ctl_fd, &opts->ctl_fd_ack); + return evlist__parse_control(str, &opts->ctl_fd, &opts->ctl_fd_ack, &opts->ctl_fd_close); +} + +static void close_control_option(struct record_opts *opts) +{ + if (opts->ctl_fd_close) { + opts->ctl_fd_close = false; + close(opts->ctl_fd); + if (opts->ctl_fd_ack >= 0) + close(opts->ctl_fd_ack); + } } static void switch_output_size_warn(struct record *rec) @@ -2578,9 +2588,10 @@ static struct option __record_options[] = { "libpfm4 event selector. use 'perf list' to list available events", parse_libpfm_events_option), #endif - OPT_CALLBACK(0, "control", &record.opts, "fd:ctl-fd[,ack-fd]", + OPT_CALLBACK(0, "control", &record.opts, "fd:ctl-fd[,ack-fd] or fifo:ctl-fifo[,ack-fifo]", "Listen on ctl-fd descriptor for command to control measurement ('enable': enable events, 'disable': disable events).\n" - "\t\t\t Optionally send control command completion ('ack\\n') to ack-fd descriptor.", + "\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_END() }; @@ -2653,12 +2664,14 @@ int cmd_record(int argc, const char **argv) !perf_can_record_switch_events()) { ui__error("kernel does not support recording context switch events\n"); parse_options_usage(record_usage, record_options, "switch-events", 0); - return -EINVAL; + err = -EINVAL; + goto out_opts; } if (switch_output_setup(rec)) { parse_options_usage(record_usage, record_options, "switch-output", 0); - return -EINVAL; + err = -EINVAL; + goto out_opts; } if (rec->switch_output.time) { @@ -2669,8 +2682,10 @@ int cmd_record(int argc, const char **argv) if (rec->switch_output.num_files) { rec->switch_output.filenames = calloc(sizeof(char *), rec->switch_output.num_files); - if (!rec->switch_output.filenames) - return -EINVAL; + if (!rec->switch_output.filenames) { + err = -EINVAL; + goto out_opts; + } } /* @@ -2686,7 +2701,8 @@ int cmd_record(int argc, const char **argv) rec->affinity_mask.bits = bitmap_alloc(rec->affinity_mask.nbits); if (!rec->affinity_mask.bits) { pr_err("Failed to allocate thread mask for %zd cpus\n", rec->affinity_mask.nbits); - return -ENOMEM; + err = -ENOMEM; + goto out_opts; } pr_debug2("thread mask[%zd]: empty\n", rec->affinity_mask.nbits); } @@ -2817,6 +2833,8 @@ out: evlist__delete(rec->evlist); symbol__exit(); auxtrace_record__free(rec->itr); +out_opts: + close_control_option(&rec->opts); return err; } diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index ea072d4..1468871 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -1047,7 +1047,17 @@ static int parse_control_option(const struct option *opt, { struct perf_stat_config *config = opt->value; - return evlist__parse_control(str, &config->ctl_fd, &config->ctl_fd_ack); + return evlist__parse_control(str, &config->ctl_fd, &config->ctl_fd_ack, &config->ctl_fd_close); +} + +static void close_control_option(struct perf_stat_config *config) +{ + if (config->ctl_fd_close) { + config->ctl_fd_close = false; + close(config->ctl_fd); + if (config->ctl_fd_ack >= 0) + close(config->ctl_fd_ack); + } } static struct option stat_options[] = { @@ -1153,9 +1163,10 @@ static struct option stat_options[] = { "libpfm4 event selector. use 'perf list' to list available events", parse_libpfm_events_option), #endif - OPT_CALLBACK(0, "control", &stat_config, "fd:ctl-fd[,ack-fd]", + OPT_CALLBACK(0, "control", &stat_config, "fd:ctl-fd[,ack-fd] or fifo:ctl-fifo[,ack-fifo]", "Listen on ctl-fd descriptor for command to control measurement ('enable': enable events, 'disable': disable events).\n" - "\t\t\t Optionally send control command completion ('ack\\n') to ack-fd descriptor.", + "\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_END() }; @@ -2398,6 +2409,7 @@ out: metricgroup__rblist_exit(&stat_config.metric_events); runtime_stat_delete(&stat_config); + close_control_option(&stat_config); return status; } diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 47d1045..00593e5 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1727,12 +1727,63 @@ struct evsel *perf_evlist__reset_weak_group(struct evlist *evsel_list, return leader; } -int evlist__parse_control(const char *str, int *ctl_fd, int *ctl_fd_ack) +static int evlist__parse_control_fifo(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close) +{ + char *s, *p; + int ret = 0, fd; + + if (strncmp(str, "fifo:", 5)) + return -EINVAL; + + str += 5; + if (!*str || *str == ',') + return -EINVAL; + + s = strdup(str); + if (!s) + return -ENOMEM; + + p = strchr(s, ','); + if (p) + *p = '\0'; + + /* + * O_RDWR avoids POLLHUPs which is necessary to allow the other + * end of a FIFO to be repeatedly opened and closed. + */ + fd = open(s, O_RDWR | O_NONBLOCK | O_CLOEXEC); + if (fd < 0) { + pr_err("Failed to open '%s'\n", s); + ret = -errno; + goto out_free; + } + *ctl_fd = fd; + *ctl_fd_close = true; + + if (p && *++p) { + /* O_RDWR | O_NONBLOCK means the other end need not be open */ + fd = open(p, O_RDWR | O_NONBLOCK | O_CLOEXEC); + if (fd < 0) { + pr_err("Failed to open '%s'\n", p); + ret = -errno; + goto out_free; + } + *ctl_fd_ack = fd; + } + +out_free: + free(s); + return ret; +} + +int evlist__parse_control(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close) { char *comma = NULL, *endptr = NULL; + *ctl_fd_close = false; + if (strncmp(str, "fd:", 3)) - return -EINVAL; + return evlist__parse_control_fifo(str, ctl_fd, ctl_fd_ack, ctl_fd_close); *ctl_fd = strtoul(&str[3], &endptr, 0); if (endptr == &str[3]) diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h index a5a5a07..a5678eb 100644 --- a/tools/perf/util/evlist.h +++ b/tools/perf/util/evlist.h @@ -373,7 +373,7 @@ enum evlist_ctl_cmd { EVLIST_CTL_CMD_ACK }; -int evlist__parse_control(const char *str, int *ctl_fd, int *ctl_fd_ack); +int evlist__parse_control(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close); int evlist__initialize_ctlfd(struct evlist *evlist, int ctl_fd, int ctl_fd_ack); int evlist__finalize_ctlfd(struct evlist *evlist); bool evlist__ctlfd_initialized(struct evlist *evlist); diff --git a/tools/perf/util/record.h b/tools/perf/util/record.h index 03678ff..266760a 100644 --- a/tools/perf/util/record.h +++ b/tools/perf/util/record.h @@ -73,6 +73,7 @@ struct record_opts { unsigned int nr_threads_synthesize; int ctl_fd; int ctl_fd_ack; + bool ctl_fd_close; }; extern const char * const *record_usage; diff --git a/tools/perf/util/stat.h b/tools/perf/util/stat.h index aa3bed4..9911fc6 100644 --- a/tools/perf/util/stat.h +++ b/tools/perf/util/stat.h @@ -136,6 +136,7 @@ struct perf_stat_config { struct rblist metric_events; int ctl_fd; int ctl_fd_ack; + bool ctl_fd_close; }; void perf_stat__set_big_num(int set); -- 2.7.4