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>

3 files changed, 12 insertions, 1 deletions

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index b766eb608b97..eb880efbce16 100644
--- 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 33804740e2ca..53187c501ee8 100644
--- 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 5421fd2ad383..24316458be20 100644
--- 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;