[PATCH v15 08/12] perf tools: Drop evlist->backward

[Wang Nan]

We are going to use evlist->backward_mmap as a container for backward
ring buffer. Since a evlist can hold normal and backward ring buffers
together, evlist->backward is useless and misleading. Drop this
indicator.

Signed-off-by: Wang Nan <wangnan0@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: He Kuang <hekuang@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Zefan Li <lizefan@xxxxxxxxxx>
Cc: Nilay Vaish <nilayvaish@xxxxxxxxx>
Cc: pi3orama@xxxxxxx
---
 tools/perf/builtin-record.c             | 11 +++++------
 tools/perf/tests/backward-ring-buffer.c |  1 -
 tools/perf/util/evlist.c                |  5 +----
 tools/perf/util/evlist.h                |  1 -
 4 files changed, 6 insertions(+), 12 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index b2b3b60..f89a4a6 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -119,11 +119,10 @@ backward_rb_find_range(void *buf, int mask, u64 head, u64 *start, u64 *end)
 }
 
 static int
-rb_find_range(struct perf_evlist *evlist,
-	      void *data, int mask, u64 head, u64 old,
-	      u64 *start, u64 *end)
+rb_find_range(void *data, int mask, u64 head, u64 old,
+	      u64 *start, u64 *end, bool backward)
 {
-	if (!evlist->backward) {
+	if (!backward) {
 		*start = old;
 		*end = head;
 		return 0;
@@ -143,8 +142,8 @@ static int record__mmap_read(struct record *rec, struct perf_evlist *evlist, int
 	void *buf;
 	int rc = 0;
 
-	if (rb_find_range(evlist, data, md->mask, head,
-			  old, &start, &end))
+	if (rb_find_range(data, md->mask, head,
+			  old, &start, &end, false))
 		return -1;
 
 	if (start == end)
diff --git a/tools/perf/tests/backward-ring-buffer.c b/tools/perf/tests/backward-ring-buffer.c
index 3558db7..e18fd03 100644
--- a/tools/perf/tests/backward-ring-buffer.c
+++ b/tools/perf/tests/backward-ring-buffer.c
@@ -101,7 +101,6 @@ int test__backward_ring_buffer(int subtest __maybe_unused)
 		return TEST_FAIL;
 	}
 
-	evlist->backward = true;
 	err = perf_evlist__create_maps(evlist, &opts.target);
 	if (err < 0) {
 		pr_debug("Not enough memory to create thread/cpu maps\n");
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 6741ced..6fb693c 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -44,7 +44,6 @@ void perf_evlist__init(struct perf_evlist *evlist, struct cpu_map *cpus,
 	perf_evlist__set_maps(evlist, cpus, threads);
 	fdarray__init(&evlist->pollfd, 64);
 	evlist->workload.pid = -1;
-	evlist->backward = false;
 }
 
 struct perf_evlist *perf_evlist__new(void)
@@ -853,9 +852,7 @@ union perf_event *perf_evlist__mmap_read_backward(struct perf_evlist *evlist, in
 
 union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx)
 {
-	if (!evlist->backward)
-		return perf_evlist__mmap_read_forward(evlist, idx);
-	return perf_evlist__mmap_read_backward(evlist, idx);
+	return perf_evlist__mmap_read_forward(evlist, idx);
 }
 
 void perf_mmap__read_catchup(struct perf_mmap *md)
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 8acac5f..72b9ff7 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -50,7 +50,6 @@ struct perf_evlist {
 	bool		 overwrite;
 	bool		 enabled;
 	bool		 has_user_cpus;
-	bool		 backward;
 	size_t		 mmap_len;
 	int		 id_pos;
 	int		 is_pos;
-- 
1.8.3.4