On Fri, 22 May 2026 13:09:05 -0400
Steven Rostedt <[email protected]> wrote:
> @@ -7187,6 +7190,8 @@ int ring_buffer_read_page(struct trace_buffer *buffer,
> local_set(&reader->entries, 0);
> reader->read = 0;
> data_page->data = dpage;
> + if (!missed_events && rb_data_page_commit(dpage) &
> RB_MISSED_EVENTS)
> + missed_events = -1;
>
> /*
> * Use the real_end for the data size,
> @@ -7204,10 +7209,12 @@ int ring_buffer_read_page(struct trace_buffer *buffer,
> * Set a flag in the commit field if we lost events
> */
> if (missed_events) {
> - /* If there is room at the end of the page to save the
> + /*
> + * If there is room at the end of the page to save the
> * missed events, then record it there.
> */
> - if (buffer->subbuf_size - commit >= sizeof(missed_events)) {
> + if (missed_events > 0 &&
> + buffer->subbuf_size - commit >= sizeof(missed_events)) {
> memcpy(&dpage->data[commit], &missed_events,
> sizeof(missed_events));
> local_add(RB_MISSED_STORED, &dpage->commit);
After this line, we "add" RB_MISSED_EVENTS instead of set.
In this case, does it clear the RB_MISSED_EVENTS bit because
it already sets RB_MISSED_EVENTS.
commit += sizeof(missed_events);
}
local_add(RB_MISSED_EVENTS, &bpage->commit);
^^^ here.
Thanks,
--
Masami Hiramatsu (Google) <[email protected]>
