diff options
| -rw-r--r-- | tools/perf/util/mmap.c | 12 | ||||
| -rw-r--r-- | 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); |