perf tools: Improve support for sessions with multiple events

By creating an perf_evlist out of the attributes in the perf.data file
header, so that we can use evlists and evsels when reading recorded
sessions in addition to when we record sessions.

More work is needed to allow tools to allow the user to select which
events are wanted when browsing sessions, be it just one or a subset of
them, aggregated or showed at the same time but with different
indications on the UI to allow seeing workloads thru different views at
the same time.

But the overall goal/trend is to more uniformly use evsels and evlists.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-annotate.c

@@ -19,6 +19,8 @@
 #include "perf.h"
 #include "util/debug.h"
 
+#include "util/evlist.h"
+#include "util/evsel.h"
 #include "util/annotate.h"
 #include "util/event.h"
 #include "util/parse-options.h"
@@ -38,9 +40,13 @@ static bool		print_line;
 
 static const char *sym_hist_filter;
 
-static int hists__add_entry(struct hists *self, struct addr_location *al)
+static int perf_evlist__add_sample(struct perf_evlist *evlist,
+				   struct perf_sample *sample,
+				   struct addr_location *al)
 {
+	struct perf_evsel *evsel;
 	struct hist_entry *he;
+	int ret;
 
 	if (sym_hist_filter != NULL &&
 	    (al->sym == NULL || strcmp(sym_hist_filter, al->sym->name) != 0)) {
@@ -53,23 +59,35 @@ static int hists__add_entry(struct hists *self, struct addr_location *al)
 		return 0;
 	}
 
-	he = __hists__add_entry(self, al, NULL, 1);
+	evsel = perf_evlist__id2evsel(evlist, sample->id);
+	if (evsel == NULL) {
+		/*
+		 * FIXME: Propagate this back, but at least we're in a builtin,
+		 * where exit() is allowed. ;-)
+		 */
+		ui__warning("Invalid %s file, contains samples with id not in "
+			    "its header!\n", input_name);
+		exit_browser(0);
+		exit(1);
+	}
+
+	he = __hists__add_entry(&evsel->hists, al, NULL, 1);
 	if (he == NULL)
 		return -ENOMEM;
 
+	ret = 0;
 	if (he->ms.sym != NULL) {
-		/*
-		 * All aggregated on the first sym_hist.
-		 */
 		struct annotation *notes = symbol__annotation(he->ms.sym);
 		if (notes->src == NULL &&
-		    symbol__alloc_hist(he->ms.sym, 1) < 0)
+		    symbol__alloc_hist(he->ms.sym, evlist->nr_entries) < 0)
 			return -ENOMEM;
 
-		return hist_entry__inc_addr_samples(he, 0, al->addr);
+		ret = hist_entry__inc_addr_samples(he, evsel->idx, al->addr);
 	}
 
-	return 0;
+	evsel->hists.stats.total_period += sample->period;
+	hists__inc_nr_events(&evsel->hists, PERF_RECORD_SAMPLE);
+	return ret;
 }
 
 static int process_sample_event(union perf_event *event,
@@ -85,7 +103,7 @@ static int process_sample_event(union perf_event *event,
 		return -1;
 	}
 
-	if (!al.filtered && hists__add_entry(&session->hists, &al)) {
+	if (!al.filtered && perf_evlist__add_sample(session->evlist, sample, &al)) {
 		pr_warning("problem incrementing symbol count, "
 			   "skipping event\n");
 		return -1;
@@ -100,7 +118,7 @@ static int hist_entry__tty_annotate(struct hist_entry *he, int evidx)
 				    print_line, full_paths, 0, 0);
 }
 
-static void hists__find_annotations(struct hists *self)
+static void hists__find_annotations(struct hists *self, int evidx)
 {
 	struct rb_node *nd = rb_first(&self->entries), *next;
 	int key = KEY_RIGHT;
@@ -123,8 +141,7 @@ static void hists__find_annotations(struct hists *self)
 		}
 
 		if (use_browser > 0) {
-			/* For now all is aggregated on the first */
-			key = hist_entry__tui_annotate(he, 0);
+			key = hist_entry__tui_annotate(he, evidx);
 			switch (key) {
 			case KEY_RIGHT:
 				next = rb_next(nd);
@@ -139,8 +156,7 @@ static void hists__find_annotations(struct hists *self)
 			if (next != NULL)
 				nd = next;
 		} else {
-			/* For now all is aggregated on the first */
-			hist_entry__tty_annotate(he, 0);
+			hist_entry__tty_annotate(he, evidx);
 			nd = rb_next(nd);
 			/*
 			 * Since we have a hist_entry per IP for the same
@@ -166,6 +182,8 @@ static int __cmd_annotate(void)
 {
 	int ret;
 	struct perf_session *session;
+	struct perf_evsel *pos;
+	u64 total_nr_samples;
 
 	session = perf_session__new(input_name, O_RDONLY, force, false, &event_ops);
 	if (session == NULL)
@@ -186,12 +204,36 @@ static int __cmd_annotate(void)
 	if (verbose > 2)
 		perf_session__fprintf_dsos(session, stdout);
 
-	hists__collapse_resort(&session->hists);
-	hists__output_resort(&session->hists);
-	hists__find_annotations(&session->hists);
-out_delete:
-	perf_session__delete(session);
+	total_nr_samples = 0;
+	list_for_each_entry(pos, &session->evlist->entries, node) {
+		struct hists *hists = &pos->hists;
+		u32 nr_samples = hists->stats.nr_events[PERF_RECORD_SAMPLE];
+
+		if (nr_samples > 0) {
+			total_nr_samples += nr_samples;
+			hists__collapse_resort(hists);
+			hists__output_resort(hists);
+			hists__find_annotations(hists, pos->idx);
+		}
+	}
 
+	if (total_nr_samples == 0) {
+		ui__warning("The %s file has no samples!\n", input_name);
+		goto out_delete;
+	}
+out_delete:
+	/*
+	 * Speed up the exit process, for large files this can
+	 * take quite a while.
+	 *
+	 * XXX Enable this when using valgrind or if we ever
+	 * librarize this command.
+	 *
+	 * Also experiment with obstacks to see how much speed
+	 * up we'll get here.
+	 *
+	 * perf_session__delete(session);
+	 */
 	return ret;
 }