Em Mon, Mar 05, 2018 at 02:10:53PM -0500, kan.li...@linux.intel.com escreveu:
> From: Kan Liang <kan.li...@linux.intel.com>
>
> There are too many boilerplates for the perf_mmap__read*() interfaces.
>
> Some of the data (e.g. 'start', 'end', 'overwrite') should be stored in
> struct perf_mmap at initialization. They will be used later.
>
> No functional change.
>
> Signed-off-by: Kan Liang <kan.li...@linux.intel.com>
> ---
> tools/perf/util/mmap.c | 11 ++++++++---
> tools/perf/util/mmap.h | 3 +++
> 2 files changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c
> index 4f27c46..642b479 100644
> --- a/tools/perf/util/mmap.c
> +++ b/tools/perf/util/mmap.c
> @@ -250,11 +250,14 @@ int perf_mmap__read_init(struct perf_mmap *md, bool
> overwrite,
>
> *startp = overwrite ? head : old;
> *endp = overwrite ? old : head;
Why did you keep the above and haven't removed the startp/endp args? to
ease the conversion somehow? I'll look at the other patches, but I think
we should change the function signature here and in the callers all at
once.
Sometimes this is ok, and probably this is one case.
- Arnaldo
> + md->overwrite = overwrite;
> + md->start = overwrite ? head : old;
> + md->end = overwrite ? old : head;
>
> - if (*startp == *endp)
> + if (md->start == md->end)
> return -EAGAIN;
>
> - size = *endp - *startp;
> + size = md->end - md->start;
> if (size > (unsigned long)(md->mask) + 1) {
> if (!overwrite) {
> WARN_ONCE(1, "failed to keep up with mmap data. (warn
> only once)\n");
> @@ -268,8 +271,10 @@ int perf_mmap__read_init(struct perf_mmap *md, bool
> overwrite,
> * Backward ring buffer is full. We still have a chance to read
> * most of data from it.
> */
> - if (overwrite_rb_find_range(data, md->mask, head, startp, endp))
> + if (overwrite_rb_find_range(data, md->mask, head, &md->start,
> &md->end))
> return -EINVAL;
> + *startp = md->start;
> + *endp = md->end;
> }
>
> return 0;
> diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h
> index ec7d3a24..9359e93 100644
> --- a/tools/perf/util/mmap.h
> +++ b/tools/perf/util/mmap.h
> @@ -20,6 +20,9 @@ struct perf_mmap {
> int fd;
> refcount_t refcnt;
> u64 prev;
> + u64 start;
> + u64 end;
> + bool overwrite;
> struct auxtrace_mmap auxtrace_mmap;
> char event_copy[PERF_SAMPLE_MAX_SIZE] __aligned(8);
> };
> --
> 2.4.11
