Commit e29386c8 authored by Jiri Olsa's avatar Jiri Olsa Committed by Arnaldo Carvalho de Melo
Browse files

perf record: Add --buildid-mmap option to enable PERF_RECORD_MMAP2's build id 



Add --buildid-mmap option to enable build id in PERF_RECORD_MMAP2 events.

It will only work if there's kernel support for that and it disables
build id cache (implies --no-buildid).

It's also possible to enable it permanently via config option in
~/.perfconfig file:

  [record]
  build-id=mmap

Also added build_id bit in the verbose output for perf_event_attr:

  # perf record --buildid-mmap -vv
  ...
  perf_event_attr:
    type                             1
    size                             120
    ...
    build_id                         1

Adding also missing text_poke bit.

Committer testing:

  $ perf record -h build

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -B, --no-buildid      do not collect buildids in perf.data
      -N, --no-buildid-cache
                            do not update the buildid cache
          --buildid-all     Record build-id of all DSOs regardless of hits
          --buildid-mmap    Record build-id in map events

  $

  $ perf record --buildid-mmap sleep 1
  Failed: no support to record build id in mmap events, update your kernel.
  $

After adding the needed kernel bits in a test kernel:

  $ perf record -vv --buildid-mmap sleep 1 |& grep -m1 build
  Enabling build id in mmap2 events.
  $ perf evlist -v
  cycles:u: size: 120, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, read_format: ID, disabled: 1, inherit: 1, exclude_kernel: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1, build_id: 1
  $

Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: default avatarIan Rogers <irogers@google.com>
Acked-by: default avatarNamhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Budankov <abudankov@huawei.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20201214105457.543111-16-jolsa@kernel.org


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 4183a8d7

tools/perf/Documentation/perf-config.txt

+2 −1
Original line number Diff line number Diff line
@@ -552,11 +552,12 @@ kmem.*:: 


record.*::

	record.build-id::

		This option can be 'cache', 'no-cache' or 'skip'.

		This option can be 'cache', 'no-cache', 'skip' or 'mmap'.

		'cache' is to post-process data and save/update the binaries into

		the build-id cache (in ~/.debug). This is the default.

		But if this option is 'no-cache', it will not update the build-id cache.

		'skip' skips post-processing and does not update the cache.

		'mmap' skips post-processing and reads build-ids from MMAP events.



	record.call-graph::

		This is identical to 'call-graph.record-mode', except it is

tools/perf/Documentation/perf-record.txt

+3 −0
Original line number Diff line number Diff line
@@ -485,6 +485,9 @@ Specify vmlinux path which has debuginfo. 
--buildid-all::

Record build-id of all DSOs regardless whether it's actually hit or not.



--buildid-mmap::

Record build ids in mmap2 events, disables build id cache (implies --no-buildid).



--aio[=n]::

Use <n> control blocks in asynchronous (Posix AIO) trace writing mode (default: 1, max: 4).

Asynchronous mode is supported only when linking Perf tool with libc library

tools/perf/builtin-record.c

+20 −0
Original line number Diff line number Diff line
@@ -102,6 +102,7 @@ struct record { 
	bool			no_buildid_cache;

	bool			no_buildid_cache_set;

	bool			buildid_all;

	bool			buildid_mmap;

	bool			timestamp_filename;

	bool			timestamp_boundary;

	struct switch_output	switch_output;
@@ -2135,6 +2136,8 @@ static int perf_record_config(const char *var, const char *value, void *cb) 
			rec->no_buildid_cache = true;

		else if (!strcmp(value, "skip"))

			rec->no_buildid = true;

		else if (!strcmp(value, "mmap"))

			rec->buildid_mmap = true;

		else

			return -1;

		return 0;
@@ -2552,6 +2555,8 @@ static struct option __record_options[] = { 
		   "file", "vmlinux pathname"),

	OPT_BOOLEAN(0, "buildid-all", &record.buildid_all,

		    "Record build-id of all DSOs regardless of hits"),

	OPT_BOOLEAN(0, "buildid-mmap", &record.buildid_mmap,

		    "Record build-id in map events"),

	OPT_BOOLEAN(0, "timestamp-filename", &record.timestamp_filename,

		    "append timestamp to output filename"),

	OPT_BOOLEAN(0, "timestamp-boundary", &record.timestamp_boundary,
@@ -2655,6 +2660,21 @@ int cmd_record(int argc, const char **argv) 


	}



	if (rec->buildid_mmap) {

		if (!perf_can_record_build_id()) {

			pr_err("Failed: no support to record build id in mmap events, update your kernel.\n");

			err = -EINVAL;

			goto out_opts;

		}

		pr_debug("Enabling build id in mmap2 events.\n");

		/* Enable mmap build id synthesizing. */

		symbol_conf.buildid_mmap2 = true;

		/* Enable perf_event_attr::build_id bit. */

		rec->opts.build_id = true;

		/* Disable build id cache. */

		rec->no_buildid = true;

	}



	if (rec->opts.kcore)

		rec->data.is_dir = true;

tools/perf/util/evsel.c

+6 −4
Original line number Diff line number Diff line
@@ -1172,6 +1172,8 @@ void evsel__config(struct evsel *evsel, struct record_opts *opts, 
	attr->mmap     = track;

	attr->mmap2    = track && !perf_missing_features.mmap2;

	attr->comm     = track;

	attr->build_id = track && opts->build_id;



	/*

	 * ksymbol is tracked separately with text poke because it needs to be

	 * system wide and enabled immediately.

tools/perf/util/perf_api_probe.c

+10 −0
Original line number Diff line number Diff line
@@ -98,6 +98,11 @@ static void perf_probe_text_poke(struct evsel *evsel) 
	evsel->core.attr.text_poke = 1;

}



static void perf_probe_build_id(struct evsel *evsel)

{

	evsel->core.attr.build_id = 1;

}



bool perf_can_sample_identifier(void)

{

	return perf_probe_api(perf_probe_sample_identifier);
@@ -172,3 +177,8 @@ bool perf_can_aux_sample(void) 


	return true;

}



bool perf_can_record_build_id(void)

{

	return perf_probe_api(perf_probe_build_id);

}