Messages in this thread | | | From | "Liang, Kan" <> | Subject | RE: [PATCH V3 04/12] perf mmap: introduce perf_mmap__read_done | Date | Thu, 11 Jan 2018 21:27:20 +0000 |
| |
> On Thu, Dec 21, 2017 at 10:08:46AM -0800, kan.liang@intel.com wrote: > > From: Kan Liang <kan.liang@intel.com> > > > > The direction of overwrite mode is backward. The last mmap__read_event > > 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> > > --- > > tools/perf/util/mmap.c | 11 +++++++++++ > > tools/perf/util/mmap.h | 1 + > > 2 files changed, 12 insertions(+) > > > > diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c > > index a844a2f..4aaeb64 100644 > > --- a/tools/perf/util/mmap.c > > +++ b/tools/perf/util/mmap.c > > @@ -343,3 +343,14 @@ 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 mmap__read_event will set tail to map->prev. > > you mean perf_mmap__read function in this comment, right? >
Right. Will fix it in V4.
Thanks, Kan
> jirka > > > + * 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 abe9b9f..2df27c1 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 *map, bool overwrite, > > u64 *start, u64 *end); > > +void perf_mmap__read_done(struct perf_mmap *map); > > #endif /*__PERF_MMAP_H */ > > -- > > 2.5.5 > >
| |