perf record: Stop intercepting events, use postprocessing to get build-ids

We want to stream events as fast as possible to perf.data, and
also in the future we want to have splice working, when no
interception will be possible.

Using build_id__mark_dso_hit_ops to create the list of DSOs that
back MMAPs we also optimize disk usage in the build-id cache by
only caching DSOs that had hits.

Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1265223128-11786-6-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 38 insertions, 26 deletions

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index aa8a03120bbd..74cbc64a3a3c 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -385,8 +385,9 @@ static struct thread *perf_session__register_idle_thread(struct perf_session *se
 	return thread;
 }
 
-int perf_session__process_events(struct perf_session *self,
-				 struct perf_event_ops *ops)
+int __perf_session__process_events(struct perf_session *self,
+				   u64 data_offset, u64 data_size,
+				   u64 file_size, struct perf_event_ops *ops)
 {
 	int err, mmap_prot, mmap_flags;
 	u64 head, shift;
@@ -396,32 +397,11 @@ int perf_session__process_events(struct perf_session *self,
 	uint32_t size;
 	char *buf;
 
-	if (perf_session__register_idle_thread(self) == NULL)
-		return -ENOMEM;
-
 	perf_event_ops__fill_defaults(ops);
 
 	page_size = sysconf(_SC_PAGESIZE);
 
-	head = self->header.data_offset;
-
-	if (!symbol_conf.full_paths) {
-		char bf[PATH_MAX];
-
-		if (getcwd(bf, sizeof(bf)) == NULL) {
-			err = -errno;
-out_getcwd_err:
-			pr_err("failed to get the current directory\n");
-			goto out_err;
-		}
-		self->cwd = strdup(bf);
-		if (self->cwd == NULL) {
-			err = -ENOMEM;
-			goto out_getcwd_err;
-		}
-		self->cwdlen = strlen(self->cwd);
-	}
-
+	head = data_offset;
 	shift = page_size * (head / page_size);
 	offset += shift;
 	head -= shift;
@@ -486,10 +466,10 @@ more:
 
 	head += size;
 
-	if (offset + head >= self->header.data_offset + self->header.data_size)
+	if (offset + head >= data_offset + data_size)
 		goto done;
 
-	if (offset + head < self->size)
+	if (offset + head < file_size)
 		goto more;
 done:
 	err = 0;
@@ -497,6 +477,38 @@ out_err:
 	return err;
 }
 
+int perf_session__process_events(struct perf_session *self,
+				 struct perf_event_ops *ops)
+{
+	int err;
+
+	if (perf_session__register_idle_thread(self) == NULL)
+		return -ENOMEM;
+
+	if (!symbol_conf.full_paths) {
+		char bf[PATH_MAX];
+
+		if (getcwd(bf, sizeof(bf)) == NULL) {
+			err = -errno;
+out_getcwd_err:
+			pr_err("failed to get the current directory\n");
+			goto out_err;
+		}
+		self->cwd = strdup(bf);
+		if (self->cwd == NULL) {
+			err = -ENOMEM;
+			goto out_getcwd_err;
+		}
+		self->cwdlen = strlen(self->cwd);
+	}
+
+	err = __perf_session__process_events(self, self->header.data_offset,
+					     self->header.data_size,
+					     self->size, ops);
+out_err:
+	return err;
+}
+
 bool perf_session__has_traces(struct perf_session *self, const char *msg)
 {
 	if (!(self->sample_type & PERF_SAMPLE_RAW)) {