diff options
| author | Kan Liang <kan.liang@intel.com> | 2018-01-18 13:26:22 -0800 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2018-02-15 09:53:15 -0300 |
| commit | ee023de05f35484691f7d9e5c1f92195ac4d64d2 (patch) | |
| tree | 8a8457fb8ee19410155576a65f6f197c0d53342f | |
| parent | b4b036b4c76341a5034e872aca3727c4988a7304 (diff) | |
perf mmap: Introduce perf_mmap__read_done()
The direction of overwrite mode is backward. The last perf_mmap__read()
will set tail to map->prev. Need to correct the map->prev to head which
is the end of next read.
It will be used later.
Signed-off-by: Kan Liang <kan.liang@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1516310792-208685-8-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| -rw-r--r-- | tools/perf/util/mmap.c | 11 | ||||
| -rw-r--r-- | tools/perf/util/mmap.h | 1 |
2 files changed, 12 insertions, 0 deletions
diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c index 125bfda9d037..4f59eaefc706 100644 --- a/tools/perf/util/mmap.c +++ b/tools/perf/util/mmap.c @@ -338,3 +338,14 @@ int perf_mmap__push(struct perf_mmap *md, bool overwrite, out: return rc; } + +/* + * Mandatory for overwrite mode + * The direction of overwrite mode is backward. + * The last perf_mmap__read() will set tail to map->prev. + * Need to correct the map->prev to head which is the end of next read. + */ +void perf_mmap__read_done(struct perf_mmap *map) +{ + map->prev = perf_mmap__read_head(map); +} diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h index 9ab2b48df65b..95549d4af943 100644 --- a/tools/perf/util/mmap.h +++ b/tools/perf/util/mmap.h @@ -96,4 +96,5 @@ size_t perf_mmap__mmap_len(struct perf_mmap *map); int perf_mmap__read_init(struct perf_mmap *md, bool overwrite, u64 *startp, u64 *endp); +void perf_mmap__read_done(struct perf_mmap *map); #endif /*__PERF_MMAP_H */ |