diff options
| author | Steven Rostedt (Google) <rostedt@goodmis.org> | 2022-09-27 19:15:24 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-10-26 12:34:30 +0200 |
| commit | bc6d4e9d64845110948546d750f14538aa84d01a (patch) | |
| tree | 720a077e7f11b51f459731f88fd97bef91102b16 /kernel | |
| parent | e8d116738514f5d3cd2a09f812e576be281e7a5f (diff) | |
ring-buffer: Have the shortest_full queue be the shortest not longest
commit 3b19d614b61b93a131f463817e08219c9ce1fee3 upstream.
The logic to know when the shortest waiters on the ring buffer should be
woken up or not has uses a less than instead of a greater than compare,
which causes the shortest_full to actually be the longest.
Link: https://lkml.kernel.org/r/20220927231823.718039222@goodmis.org
Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 2c2b0a78b3739 ("ring-buffer: Add percentage of ring buffer full to wake up reader")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/ring_buffer.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 2e65ebb809c1..07e274e769db 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -975,7 +975,7 @@ int ring_buffer_wait(struct trace_buffer *buffer, int cpu, int full) nr_pages = cpu_buffer->nr_pages; dirty = ring_buffer_nr_dirty_pages(buffer, cpu); if (!cpu_buffer->shortest_full || - cpu_buffer->shortest_full < full) + cpu_buffer->shortest_full > full) cpu_buffer->shortest_full = full; raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); if (!pagebusy && |