[tip:perf/core] perf evlist: Introduce backward_mmap array for evlist

From: tip-bot for Wang Nan
Date: Sat Jul 16 2016 - 16:48:43 EST


Commit-ID: b2cb615d8aaba520fe351ff456f6c7730828b3fe
Gitweb: http://git.kernel.org/tip/b2cb615d8aaba520fe351ff456f6c7730828b3fe
Author: Wang Nan <wangnan0@xxxxxxxxxx>
AuthorDate: Thu, 14 Jul 2016 08:34:39 +0000
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Fri, 15 Jul 2016 17:27:48 -0300

perf evlist: Introduce backward_mmap array for evlist

Add backward_mmap to evlist, free it together with normal mmap.

Improve perf_evlist__pick_pc(), search backward_mmap if evlist->mmap is
not available.

This patch doesn't alloc this array. It will be allocated conditionally
in the following commits.

Signed-off-by: Wang Nan <wangnan0@xxxxxxxxxx>
Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: He Kuang <hekuang@xxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Nilay Vaish <nilayvaish@xxxxxxxxx>
Cc: Zefan Li <lizefan@xxxxxxxxxx>
Cc: pi3orama@xxxxxxx
Link: http://lkml.kernel.org/r/1468485287-33422-8-git-send-email-wangnan0@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-record.c | 10 +++++++---
tools/perf/util/evlist.c | 12 ++++++++----
tools/perf/util/evlist.h | 1 +
3 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index d15517e..dbcb223 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -509,7 +509,7 @@ static int record__mmap_read_evlist(struct record *rec, struct perf_evlist *evli
if (!evlist)
return 0;

- maps = evlist->mmap;
+ maps = backward ? evlist->backward_mmap : evlist->mmap;
if (!maps)
return 0;

@@ -696,8 +696,12 @@ perf_event__synth_time_conv(const struct perf_event_mmap_page *pc __maybe_unused
static const struct perf_event_mmap_page *
perf_evlist__pick_pc(struct perf_evlist *evlist)
{
- if (evlist && evlist->mmap && evlist->mmap[0].base)
- return evlist->mmap[0].base;
+ if (evlist) {
+ if (evlist->mmap && evlist->mmap[0].base)
+ return evlist->mmap[0].base;
+ if (evlist->backward_mmap && evlist->backward_mmap[0].base)
+ return evlist->backward_mmap[0].base;
+ }
return NULL;
}

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 54ae0a0..24927e1 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -123,6 +123,7 @@ static void perf_evlist__purge(struct perf_evlist *evlist)
void perf_evlist__exit(struct perf_evlist *evlist)
{
zfree(&evlist->mmap);
+ zfree(&evlist->backward_mmap);
fdarray__exit(&evlist->pollfd);
}

@@ -973,17 +974,20 @@ static void perf_evlist__munmap_nofree(struct perf_evlist *evlist)
{
int i;

- if (evlist->mmap == NULL)
- return;
+ if (evlist->mmap)
+ for (i = 0; i < evlist->nr_mmaps; i++)
+ perf_mmap__munmap(&evlist->mmap[i]);

- for (i = 0; i < evlist->nr_mmaps; i++)
- perf_mmap__munmap(&evlist->mmap[i]);
+ if (evlist->backward_mmap)
+ for (i = 0; i < evlist->nr_mmaps; i++)
+ perf_mmap__munmap(&evlist->backward_mmap[i]);
}

void perf_evlist__munmap(struct perf_evlist *evlist)
{
perf_evlist__munmap_nofree(evlist);
zfree(&evlist->mmap);
+ zfree(&evlist->backward_mmap);
}

static struct perf_mmap *perf_evlist__alloc_mmap(struct perf_evlist *evlist)
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 9e680c6..07a1ad0 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -61,6 +61,7 @@ struct perf_evlist {
} workload;
struct fdarray pollfd;
struct perf_mmap *mmap;
+ struct perf_mmap *backward_mmap;
struct thread_map *threads;
struct cpu_map *cpus;
struct perf_evsel *selected;