lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Mon, 12 Oct 2020 12:13:10 +0300
From:   Alexey Budankov <alexey.budankov@...ux.intel.com>
To:     Arnaldo Carvalho de Melo <acme@...nel.org>,
        Jiri Olsa <jolsa@...hat.com>
Cc:     Namhyung Kim <namhyung@...nel.org>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Andi Kleen <ak@...ux.intel.com>,
        Adrian Hunter <adrian.hunter@...el.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>,
        linux-kernel <linux-kernel@...r.kernel.org>
Subject: [PATCH v1 15/15] perf record: introduce --threads command line option


Provide --threads option in perf record command line interface.
Threaded streaming mode mitigates profiling data losses and
resolves scalability issues of serial and asynchronous (--aio) trace
streaming modes on multicore server systems. The implementation is
based on the prototype [1], [2] and the most closely relates to mode 3)
"mode that creates thread for every monitored memory map".

Threaded streaming mode is available with Zstd compression/decompression
(--compression-level) and handling of external commands (--control).
AUX area tracing, related and derived modes like --snapshot or
--aux-sample are not enabled. --switch-output, --switch-output-event,
--switch-max-files and --timestamp-filename options are not enabled.
Threaded trace streaming is not enabled for pipe mode. Asynchronous
(--aio) trace streaming and affinity (--affinity) modes are mutually
exclusive to the exposed threaded streaming mode.

[1] git clone https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git -b perf/record_threads
[2] https://lore.kernel.org/lkml/20180913125450.21342-1-jolsa@kernel.org/

Signed-off-by: Alexey Budankov <alexey.budankov@...ux.intel.com>
---
 tools/perf/Documentation/perf-record.txt |  7 ++++
 tools/perf/builtin-record.c              | 45 +++++++++++++++++++++---
 2 files changed, 48 insertions(+), 4 deletions(-)

diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index 768888b9326a..d8fa387da973 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -671,6 +671,13 @@ Example of bash shell script to enable and disable events during measurements:
  wait -n ${perf_pid}
  exit $?
 
+--threads::
+Write collected trace data into per-CPU trace files using parallel threads.
+List of monitored CPUs can be configured by a mask provided via --cpu option.
+Trace writing threads correspond one-to-one to mapped data buffers. Threads
+and buffers are affined to monitored CPUs and NUMA nodes according to system
+topology. Threaded trace streaming mode is mutually exclusive to asynchronous
+trace streaming (--aio) and affinity (--affinity) modes.
 
 SEE ALSO
 --------
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 1d41e996a994..575b0b595081 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -780,6 +780,12 @@ static int record__auxtrace_init(struct record *rec)
 {
 	int err;
 
+	if ((rec->opts.auxtrace_snapshot_opts || rec->opts.auxtrace_sample_opts)
+	    && record__threads_enabled(rec)) {
+		pr_err("AUX area tracing options are not available in threaded streaming mode.\n");
+		return -EINVAL;
+	}
+
 	if (!rec->itr) {
 		rec->itr = auxtrace_record__init(rec->evlist, &err);
 		if (err)
@@ -2008,6 +2014,11 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
 		return PTR_ERR(session);
 	}
 
+	if (record__threads_enabled(rec) && perf_data__is_pipe(&rec->data)) {
+		pr_err("Threaded trace streaming is not available in pipe mode.\n");
+		return -1;
+	}
+
 	fd = perf_data__fd(data);
 	rec->session = session;
 
@@ -2680,12 +2691,22 @@ static int switch_output_setup(struct record *rec)
 	 * --switch-output=signal, as we'll send a SIGUSR2 from the side band
 	 *  thread to its parent.
 	 */
-	if (rec->switch_output_event_set)
+	if (rec->switch_output_event_set) {
+		if (record__threads_enabled(rec)) {
+			pr_warning("WARNING: --switch-output-event option is not available in threaded streaming mode.\n");
+			return 0;
+		}
 		goto do_signal;
+	}
 
 	if (!s->set)
 		return 0;
 
+	if (record__threads_enabled(rec)) {
+		pr_warning("WARNING: --switch-output option is not available in threaded streaming mode.\n");
+		return 0;
+	}
+
 	if (!strcmp(s->str, "signal")) {
 do_signal:
 		s->signal = true;
@@ -2964,8 +2985,8 @@ static struct option __record_options[] = {
 		     "Set affinity mask of trace reading thread to NUMA node cpu mask or cpu of processed mmap buffer",
 		     record__parse_affinity),
 #ifdef HAVE_ZSTD_SUPPORT
-	OPT_CALLBACK_OPTARG('z', "compression-level", &record.opts, &comp_level_default,
-			    "n", "Compressed records using specified level (default: 1 - fastest compression, 22 - greatest compression)",
+	OPT_CALLBACK_OPTARG('z', "compression-level", &record.opts, &comp_level_default, "n",
+			    "Compress records using specified level (default: 1 - fastest compression, 22 - greatest compression)",
 			    record__parse_comp_level),
 #endif
 	OPT_CALLBACK(0, "max-size", &record.output_max_size,
@@ -2984,6 +3005,8 @@ 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_BOOLEAN(0, "threads", &record.opts.threads,
+		    "write collected trace data into per-CPU trace files using parallel threads"),
 	OPT_END()
 };
 
@@ -3046,8 +3069,17 @@ int cmd_record(int argc, const char **argv)
 	if (rec->opts.kcore || record__threads_enabled(rec))
 		rec->data.is_dir = true;
 
-	if (record__threads_enabled(rec))
+	if (record__threads_enabled(rec)) {
+		if (rec->opts.affinity != PERF_AFFINITY_SYS) {
+			pr_err("--affinity option is mutually exclusive to threaded streaming mode.\n");
+			goto out_opts;
+		}
 		rec->opts.affinity = PERF_AFFINITY_CPU;
+		if (record__aio_enabled(rec)) {
+			pr_err("Asynchronous streaming mode (--aio) is mutually exclusive to threaded streaming mode.\n");
+			goto out_opts;
+		}
+	}
 
 	if (rec->opts.comp_level != 0) {
 		pr_debug("Compression enabled, disabling build id collection at the end of the session.\n");
@@ -3082,6 +3114,11 @@ int cmd_record(int argc, const char **argv)
 		}
 	}
 
+	if (rec->timestamp_filename && record__threads_enabled(rec)) {
+		rec->timestamp_filename = false;
+		pr_warning("WARNING: --timestamp-filename option is not available in threaded streaming mode.\n");
+	}
+
 	/*
 	 * Allow aliases to facilitate the lookup of symbols for address
 	 * filters. Refer to auxtrace_parse_filters().
-- 
2.24.1

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ