From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751949AbcFUWAM (ORCPT ); Tue, 21 Jun 2016 18:00:12 -0400 Received: from mail.kernel.org ([198.145.29.136]:60652 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751822AbcFUWAJ (ORCPT ); Tue, 21 Jun 2016 18:00:09 -0400 Date: Tue, 21 Jun 2016 18:49:40 -0300 From: Arnaldo Carvalho de Melo To: Wang Nan Cc: linux-kernel@vger.kernel.org, pi3orama@163.com, He Kuang , Arnaldo Carvalho de Melo , Jiri Olsa , Masami Hiramatsu , Namhyung Kim , Zefan Li Subject: Re: [PATCH v8 6/8] perf tools: Enable overwrite settings Message-ID: <20160621214940.GG4213@kernel.org> References: <1466419645-75551-1-git-send-email-wangnan0@huawei.com> <1466419645-75551-7-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1466419645-75551-7-git-send-email-wangnan0@huawei.com> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.6.1 (2016-04-27) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Mon, Jun 20, 2016 at 10:47:23AM +0000, Wang Nan escreveu: > This patch allows following config terms and option: > > Globally setting events to overwrite; > > # perf record --overwrite ... > > Set specific events to be overwrite or no-overwrite. > > # perf record --event cycles/overwrite/ ... > # perf record --event cycles/no-overwrite/ ... > > Add missing config terms and update config term array size because the > longest string length is changed. > > For overwritable events, automatically select attr.write_backward since > perf requires it to be backward for reading. > > Test result: > # perf record --overwrite -e syscalls:*enter_nanosleep* usleep 1 > [ perf record: Woken up 2 times to write data ] > [ perf record: Captured and wrote 0.011 MB perf.data (1 samples) ] > # perf evlist -v > syscalls:sys_enter_nanosleep: type: 2, size: 112, config: 0x134, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CPU|PERIOD|RAW, disabled: 1, inherit: 1, mmap: 1, comm: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, write_backward: 1 > # Tip: use 'perf evlist --trace-fields' to show fields for tracepoint events > > Signed-off-by: Wang Nan > Signed-off-by: He Kuang > Cc: Arnaldo Carvalho de Melo > Cc: Jiri Olsa > Cc: Masami Hiramatsu > Cc: Namhyung Kim > Cc: Zefan Li > Cc: pi3orama@163.com > --- > tools/perf/Documentation/perf-record.txt | 14 ++++++++++++++ > tools/perf/builtin-record.c | 1 + > tools/perf/perf.h | 1 + > tools/perf/tests/backward-ring-buffer.c | 15 ++++++--------- > tools/perf/util/evsel.c | 12 ++++++++++++ > tools/perf/util/evsel.h | 2 ++ > tools/perf/util/parse-events.c | 20 ++++++++++++++++++-- > tools/perf/util/parse-events.h | 2 ++ > tools/perf/util/parse-events.l | 2 ++ > 9 files changed, 58 insertions(+), 11 deletions(-) > > diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt > index 8dbee83..f5cb932 100644 > --- a/tools/perf/Documentation/perf-record.txt > +++ b/tools/perf/Documentation/perf-record.txt > @@ -360,6 +360,20 @@ particular perf.data snapshot should be kept or not. > > Implies --timestamp-filename, --no-buildid and --no-buildid-cache. > > +--overwrite:: > +Makes all events use overwritable ring buffer. Event with overwritable ring > +buffer works like a flight recorder: when buffer gets full, instead of dumping > +records into output file, kernel overwrites old records silently. Perf dumps > +data from overwritable ring buffer when switching output (see --switch-output) > +and before terminate. What about: (some other alternative paragraphs below) --------------- Makes all events use an overwritable ring buffer. An overwritable ring buffer works like a flight recorder: when it gets full, the kernel will overwrite the oldest records, that thus will never make it to the perf.data file. > + > +Perf behaves like a daemon when '--overwrite' and '--switch-output' are > +provided. It record and drop events in background, and dumps data when > +something unusual is detected. When '--overwrite' and '--switch-output' are used perf records and drops events until it receives a signal, meaning that something unusual was detected that warrants taking a snapshot of the most current events, those fitting in the ring buffer at that moment. > + > +'overwrite' attribute can also be set or canceled for specific event using an > +config terms like 'cycles/overwrite/' and 'instructions/no-overwrite/'. in > + > SEE ALSO > -------- > linkperf:perf-stat[1], linkperf:perf-list[1] > diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c > index 48c0051..bb62882 100644 > --- a/tools/perf/builtin-record.c > +++ b/tools/perf/builtin-record.c > @@ -1520,6 +1520,7 @@ struct option __record_options[] = { > OPT_BOOLEAN_SET('i', "no-inherit", &record.opts.no_inherit, > &record.opts.no_inherit_set, > "child tasks do not inherit counters"), > + OPT_BOOLEAN(0, "overwrite", &record.opts.overwrite, "use overwrite mode"), > OPT_UINTEGER('F', "freq", &record.opts.user_freq, "profile at this frequency"), > OPT_CALLBACK('m', "mmap-pages", &record.opts, "pages[,pages]", > "number of mmap data pages and AUX area tracing mmap pages", > diff --git a/tools/perf/perf.h b/tools/perf/perf.h > index cd8f1b1..608b42b 100644 > --- a/tools/perf/perf.h > +++ b/tools/perf/perf.h > @@ -59,6 +59,7 @@ struct record_opts { > bool record_switch_events; > bool all_kernel; > bool all_user; > + bool overwrite; > unsigned int freq; > unsigned int mmap_pages; > unsigned int auxtrace_mmap_pages; > diff --git a/tools/perf/tests/backward-ring-buffer.c b/tools/perf/tests/backward-ring-buffer.c > index 76e34c0..bba0b83 100644 > --- a/tools/perf/tests/backward-ring-buffer.c > +++ b/tools/perf/tests/backward-ring-buffer.c > @@ -130,27 +130,24 @@ int test__backward_ring_buffer(int subtest __maybe_unused) > } > > bzero(&parse_error, sizeof(parse_error)); > - err = parse_events(evlist, "syscalls:sys_enter_prctl", &parse_error); > + /* > + * Set backward bit, ring buffer should be writing from end. Record > + * it in aux evlist > + */ > + err = parse_events(evlist, "syscalls:sys_enter_prctl/overwrite/", &parse_error); > if (err) { > pr_debug("Failed to parse tracepoint event, try use root\n"); > ret = TEST_SKIP; > goto out_delete_evlist; > } > > - /* > - * Set backward bit, ring buffer should be writing from end. Record > - * it in aux evlist > - */ > - perf_evlist__last(evlist)->overwrite = true; > - perf_evlist__last(evlist)->attr.write_backward = 1; > - > + /* Don't set backward bit for exit event. Record it in main evlist */ > err = parse_events(evlist, "syscalls:sys_exit_prctl", &parse_error); > if (err) { > pr_debug("Failed to parse tracepoint event, try use root\n"); > ret = TEST_SKIP; > goto out_delete_evlist; > } > - /* Don't set backward bit for exit event. Record it in main evlist */ > > perf_evlist__config(evlist, &opts, NULL); > > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c > index 1d8f2bb..3629520 100644 > --- a/tools/perf/util/evsel.c > +++ b/tools/perf/util/evsel.c > @@ -677,11 +677,22 @@ static void apply_config_terms(struct perf_evsel *evsel, > */ > attr->inherit = term->val.inherit ? 1 : 0; > break; > + case PERF_EVSEL__CONFIG_TERM_OVERWRITE: > + evsel->overwrite = term->val.overwrite ? 1 : 0; > + break; > default: > break; > } > } > > + /* > + * Set backward after config term processing because it is > + * possible to set overwrite globally, without config > + * terms. > + */ > + if (evsel->overwrite) > + attr->write_backward = 1; > + > /* User explicitly set per-event callgraph, clear the old setting and reset. */ > if ((callgraph_buf != NULL) || (dump_size > 0) || max_stack) { > if (max_stack) { > @@ -758,6 +769,7 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts, > > attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1; > attr->inherit = !opts->no_inherit; > + evsel->overwrite = opts->overwrite; > > perf_evsel__set_sample_bit(evsel, IP); > perf_evsel__set_sample_bit(evsel, TID); > diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h > index 828ddd1..55ff958 100644 > --- a/tools/perf/util/evsel.h > +++ b/tools/perf/util/evsel.h > @@ -45,6 +45,7 @@ enum { > PERF_EVSEL__CONFIG_TERM_STACK_USER, > PERF_EVSEL__CONFIG_TERM_INHERIT, > PERF_EVSEL__CONFIG_TERM_MAX_STACK, > + PERF_EVSEL__CONFIG_TERM_OVERWRITE, > PERF_EVSEL__CONFIG_TERM_MAX, > }; > > @@ -59,6 +60,7 @@ struct perf_evsel_config_term { > u64 stack_user; > int max_stack; > bool inherit; > + bool overwrite; > } val; > }; > > diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c > index d15e335..b641f75 100644 > --- a/tools/perf/util/parse-events.c > +++ b/tools/perf/util/parse-events.c > @@ -901,6 +901,8 @@ static const char *config_term_names[__PARSE_EVENTS__TERM_TYPE_NR] = { > [PARSE_EVENTS__TERM_TYPE_NOINHERIT] = "no-inherit", > [PARSE_EVENTS__TERM_TYPE_INHERIT] = "inherit", > [PARSE_EVENTS__TERM_TYPE_MAX_STACK] = "max-stack", > + [PARSE_EVENTS__TERM_TYPE_OVERWRITE] = "overwrite", > + [PARSE_EVENTS__TERM_TYPE_NOOVERWRITE] = "no-overwrite", > }; > > static bool config_term_shrinked; > @@ -993,6 +995,12 @@ do { \ > case PARSE_EVENTS__TERM_TYPE_NOINHERIT: > CHECK_TYPE_VAL(NUM); > break; > + case PARSE_EVENTS__TERM_TYPE_OVERWRITE: > + CHECK_TYPE_VAL(NUM); > + break; > + case PARSE_EVENTS__TERM_TYPE_NOOVERWRITE: > + CHECK_TYPE_VAL(NUM); > + break; > case PARSE_EVENTS__TERM_TYPE_NAME: > CHECK_TYPE_VAL(STR); > break; > @@ -1045,6 +1053,8 @@ static int config_term_tracepoint(struct perf_event_attr *attr, > case PARSE_EVENTS__TERM_TYPE_INHERIT: > case PARSE_EVENTS__TERM_TYPE_NOINHERIT: > case PARSE_EVENTS__TERM_TYPE_MAX_STACK: > + case PARSE_EVENTS__TERM_TYPE_OVERWRITE: > + case PARSE_EVENTS__TERM_TYPE_NOOVERWRITE: > return config_term_common(attr, term, err); > default: > if (err) { > @@ -1117,6 +1127,12 @@ do { \ > case PARSE_EVENTS__TERM_TYPE_MAX_STACK: > ADD_CONFIG_TERM(MAX_STACK, max_stack, term->val.num); > break; > + case PARSE_EVENTS__TERM_TYPE_OVERWRITE: > + ADD_CONFIG_TERM(OVERWRITE, overwrite, term->val.num ? 1 : 0); > + break; > + case PARSE_EVENTS__TERM_TYPE_NOOVERWRITE: > + ADD_CONFIG_TERM(OVERWRITE, overwrite, term->val.num ? 0 : 1); > + break; > default: > break; > } > @@ -2330,9 +2346,9 @@ static void config_terms_list(char *buf, size_t buf_sz) > char *parse_events_formats_error_string(char *additional_terms) > { > char *str; > - /* "branch_type" is the longest name */ > + /* "no-overwrite" is the longest name */ > char static_terms[__PARSE_EVENTS__TERM_TYPE_NR * > - (sizeof("branch_type") - 1)]; > + (sizeof("no-overwrite") - 1)]; > > config_terms_list(static_terms, sizeof(static_terms)); > /* valid terms */ > diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h > index 46c05cc..1b04d82 100644 > --- a/tools/perf/util/parse-events.h > +++ b/tools/perf/util/parse-events.h > @@ -69,6 +69,8 @@ enum { > PARSE_EVENTS__TERM_TYPE_NOINHERIT, > PARSE_EVENTS__TERM_TYPE_INHERIT, > PARSE_EVENTS__TERM_TYPE_MAX_STACK, > + PARSE_EVENTS__TERM_TYPE_NOOVERWRITE, > + PARSE_EVENTS__TERM_TYPE_OVERWRITE, > __PARSE_EVENTS__TERM_TYPE_NR, > }; > > diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l > index 3c15b33..7a25194 100644 > --- a/tools/perf/util/parse-events.l > +++ b/tools/perf/util/parse-events.l > @@ -202,6 +202,8 @@ stack-size { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_STACKSIZE); } > max-stack { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_MAX_STACK); } > inherit { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_INHERIT); } > no-inherit { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_NOINHERIT); } > +overwrite { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_OVERWRITE); } > +no-overwrite { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_NOOVERWRITE); } > , { return ','; } > "/" { BEGIN(INITIAL); return '/'; } > {name_minus} { return str(yyscanner, PE_NAME); } > -- > 1.8.3.4