Commit-ID: 4fda3459e3c2e5ca35d304646aeeb811242537b2 Gitweb: https://git.kernel.org/tip/4fda3459e3c2e5ca35d304646aeeb811242537b2 Author: Kan Liang <kan.li...@linux.intel.com> AuthorDate: Tue, 6 Mar 2018 10:36:01 -0500 Committer: Arnaldo Carvalho de Melo <a...@redhat.com> CommitDate: Thu, 8 Mar 2018 10:05:50 -0300
perf mmap: Store mmap scope in struct perf_mmap() There is too much boilerplate in the perf_mmap__read*() interfaces. The 'start' and 'end' variables should be stored in struct perf_mmap at initialization. They will be used later. The old 'startp' and 'endp' pointers are used by perf_mmap__read_event() now. They cannot be removed. So the old 'startp/endp' and new 'md->start/md->end' will exist simultaneously now. The old one will be removed later. Signed-off-by: Kan Liang <kan.li...@linux.intel.com> Suggested-by: Arnaldo Carvalho de Melo <a...@redhat.com> Acked-by: Jiri Olsa <jo...@kernel.org> Cc: Andi Kleen <a...@linux.intel.com> Cc: Namhyung Kim <namhy...@kernel.org> Cc: Wang Nan <wangn...@huawei.com> Link: http://lkml.kernel.org/r/1520350567-80082-2-git-send-email-kan.li...@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/util/mmap.c | 12 ++++++++---- tools/perf/util/mmap.h | 2 ++ 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c index 4f27c464ce0b..09acaf7392bb 100644 --- a/tools/perf/util/mmap.c +++ b/tools/perf/util/mmap.c @@ -250,13 +250,15 @@ int perf_mmap__read_init(struct perf_mmap *md, bool overwrite, *startp = overwrite ? head : old; *endp = overwrite ? old : head; + md->start = md->overwrite ? head : old; + md->end = md->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) { + if (!md->overwrite) { WARN_ONCE(1, "failed to keep up with mmap data. (warn only once)\n"); md->prev = head; @@ -268,8 +270,10 @@ 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 71137977af28..9359e934ab14 100644 --- a/tools/perf/util/mmap.h +++ b/tools/perf/util/mmap.h @@ -20,6 +20,8 @@ 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);
