perf record: Add --all-cgroups option

The --all-cgroups option is to enable cgroup profiling support.  It
tells kernel to record CGROUP events in the ring buffer so that perf
report can identify task/cgroup association later.

  [root@seventh ~]# perf record --all-cgroups --namespaces /wb/cgtest
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.042 MB perf.data (558 samples) ]
  [root@seventh ~]# perf report --stdio -s cgroup_id,cgroup,pid
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 558  of event 'cycles'
  # Event count (approx.): 458017341
  #
  # Overhead  cgroup id (dev/inode)  Cgroup          Pid:Command
  # ........  .....................  ..........  ...............
  #
      33.15%  4/0xeffffffb           /sub           9615:looper0
      32.83%  4/0xf00002f5           /sub/cgrp2     9620:looper2
      32.79%  4/0xf00002f4           /sub/cgrp1     9619:looper1
       0.35%  4/0xf00002f5           /sub/cgrp2     9618:cgtest
       0.34%  4/0xf00002f4           /sub/cgrp1     9617:cgtest
       0.32%  4/0xeffffffb           /              9615:looper0
       0.11%  4/0xeffffffb           /sub           9617:cgtest
       0.10%  4/0xeffffffb           /sub           9618:cgtest

  #
  # (Tip: Sample related events with: perf record -e '{cycles,instructions}:S')
  #
  [root@seventh ~]#

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200325124536.2800725-8-namhyung@kernel.org
Link: http://lore.kernel.org/lkml/20200402015249.3800462-1-namhyung@kernel.org
[ Extracted the HAVE_FILE_HANDLE from the followup patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index b25e028458e2e664203319110fa646a1f5c143a8..b3f3b3f1c161d23e6a81a1ce6a173b3920e52260 100644 (file)
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -391,7 +391,10 @@ displayed with the weight and local_weight sort keys.  This currently works for
 abort events and some memory events in precise mode on modern Intel CPUs.
 
 --namespaces::
-Record events of type PERF_RECORD_NAMESPACES.
+Record events of type PERF_RECORD_NAMESPACES.  This enables 'cgroup_id' sort key.
+
+--all-cgroups::
+Record events of type PERF_RECORD_CGROUP.  This enables 'cgroup' sort key.
 
 --transaction::
 Record transaction flags for transaction related events.

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 2802de9538ff5fdcf544f0c75e588f92bac67ef7..1ab349abe9046949f57eaefd69e0d1f51910b937 100644 (file)
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1433,6 +1433,15 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
        if (rec->opts.record_namespaces)
                tool->namespace_events = true;
 
+       if (rec->opts.record_cgroup) {
+#ifdef HAVE_FILE_HANDLE
+               tool->cgroup_events = true;
+#else
+               pr_err("cgroup tracking is not supported\n");
+               return -1;
+#endif
+       }
+
        if (rec->opts.auxtrace_snapshot_mode || rec->switch_output.enabled) {
                signal(SIGUSR2, snapshot_sig_handler);
                if (rec->opts.auxtrace_snapshot_mode)
@@ -2363,6 +2372,8 @@ static struct option __record_options[] = {
                        "per thread proc mmap processing timeout in ms"),
        OPT_BOOLEAN(0, "namespaces", &record.opts.record_namespaces,
                    "Record namespaces events"),
+       OPT_BOOLEAN(0, "all-cgroups", &record.opts.record_cgroup,
+                   "Record cgroup events"),
        OPT_BOOLEAN(0, "switch-events", &record.opts.record_switch_events,
                    "Record context switch events"),
        OPT_BOOLEAN_FLAG(0, "all-kernel", &record.opts.all_kernel,

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index b766eb608b97765aaa6ae34aa1e032d96bd47b51..eb880efbce16dcadec399cc4530dd0ba47ee630a 100644 (file)
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1104,6 +1104,11 @@ void perf_evsel__config(struct evsel *evsel, struct record_opts *opts,
        if (opts->record_namespaces)
                attr->namespaces  = track;
 
+       if (opts->record_cgroup) {
+               attr->cgroup = track && !perf_missing_features.cgroup;
+               perf_evsel__set_sample_bit(evsel, CGROUP);
+       }
+
        if (opts->record_switch_events)
                attr->context_switch = track;
 
@@ -1789,7 +1794,11 @@ try_fallback:
         * Must probe features in the order they were added to the
         * perf_event_attr interface.
         */
-       if (!perf_missing_features.branch_hw_idx &&
+        if (!perf_missing_features.cgroup && evsel->core.attr.cgroup) {
+               perf_missing_features.cgroup = true;
+               pr_debug2_peo("Kernel has no cgroup sampling support, bailing out\n");
+               goto out_close;
+        } else if (!perf_missing_features.branch_hw_idx &&
            (evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX)) {
                perf_missing_features.branch_hw_idx = true;
                pr_debug2("switching off branch HW index support\n");

diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 33804740e2ca70610bdafea1723821b7428e679e..53187c501ee8623e255ebb50b2ab7d2b559cf2e6 100644 (file)
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -120,6 +120,7 @@ struct perf_missing_features {
        bool bpf;
        bool aux_output;
        bool branch_hw_idx;
+       bool cgroup;
 };
 
 extern struct perf_missing_features perf_missing_features;

diff --git a/tools/perf/util/record.h b/tools/perf/util/record.h
index 5421fd2ad3831b897066ddfa843d466e4f5a46b5..24316458be203e482dfeb40ebc4f5e29145353ed 100644 (file)
--- a/tools/perf/util/record.h
+++ b/tools/perf/util/record.h
@@ -34,6 +34,7 @@ struct record_opts {
        bool          auxtrace_snapshot_on_exit;
        bool          auxtrace_sample_mode;
        bool          record_namespaces;
+       bool          record_cgroup;
        bool          record_switch_events;
        bool          all_kernel;
        bool          all_user;