diff options
| -rw-r--r-- | tools/perf/util/mmap.c | 33 |
1 files changed, 15 insertions, 18 deletions
diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c index 3f262e707a41..5f8cb1583e53 100644 --- a/tools/perf/util/mmap.c +++ b/tools/perf/util/mmap.c @@ -267,18 +267,6 @@ static int backward_rb_find_range(void *buf, int mask, u64 head, u64 *start, u64 return -1; } -static int rb_find_range(void *data, int mask, u64 head, u64 old, - u64 *start, u64 *end, bool backward) -{ - if (!backward) { - *start = old; - *end = head; - return 0; - } - - return backward_rb_find_range(data, mask, head, start, end); -} - int perf_mmap__push(struct perf_mmap *md, bool backward, void *to, int push(void *to, void *buf, size_t size)) { @@ -290,19 +278,28 @@ int perf_mmap__push(struct perf_mmap *md, bool backward, void *buf; int rc = 0; - if (rb_find_range(data, md->mask, head, old, &start, &end, backward)) - return -1; + start = backward ? head : old; + end = backward ? old : head; if (start == end) return 0; size = end - start; if (size > (unsigned long)(md->mask) + 1) { - WARN_ONCE(1, "failed to keep up with mmap data. (warn only once)\n"); + if (!backward) { + WARN_ONCE(1, "failed to keep up with mmap data. (warn only once)\n"); - md->prev = head; - perf_mmap__consume(md, backward); - return 0; + md->prev = head; + perf_mmap__consume(md, backward); + return 0; + } + + /* + * Backward ring buffer is full. We still have a chance to read + * most of data from it. + */ + if (backward_rb_find_range(data, md->mask, head, &start, &end)) + return -1; } if ((start & md->mask) + size != (end & md->mask)) { |