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| author | Mark Brown <broonie@kernel.org> | 2021-09-01 17:30:37 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2021-09-01 17:30:37 +0100 |
| commit | 0f2ef911de0bdf3a0ea1d9b28e9126d3e018bbd5 (patch) | |
| tree | 7d0bc8977cc78fcf949e0b6635a0635841ff0297 /kernel/trace/ring_buffer.c | |
| parent | 222039a2503e0839f859e18e6f09acb9997480d1 (diff) | |
| parent | 38b7673000949ca784fcb8a9feb70d2a802befa6 (diff) | |
| download | linux-0f2ef911de0bdf3a0ea1d9b28e9126d3e018bbd5.tar.bz2 | |
Merge tag 'asoc-v5.15' into asoc-5.15
ASoC: Updates for v5.15
Quite a quiet release this time, mostly a combination of cleanups
and a good set of new drivers.
- Lots of cleanups and improvements to the Intel drivers,
including some new systems support.
- New support for AMD Vangoh, CUI CMM-4030D-261, Mediatek
Mt8195, Renesas RZ/G2L Mediatek Mt8195, RealTek RT101P,
Renesas RZ/G2L,, Rockchip RK3568 S/PDIF.
Diffstat (limited to 'kernel/trace/ring_buffer.c')
| -rw-r--r-- | kernel/trace/ring_buffer.c | 28 |
1 files changed, 24 insertions, 4 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index d1463eac11a3..e592d1df6f88 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -3880,10 +3880,30 @@ static bool rb_per_cpu_empty(struct ring_buffer_per_cpu *cpu_buffer) if (unlikely(!head)) return true; - return reader->read == rb_page_commit(reader) && - (commit == reader || - (commit == head && - head->read == rb_page_commit(commit))); + /* Reader should exhaust content in reader page */ + if (reader->read != rb_page_commit(reader)) + return false; + + /* + * If writers are committing on the reader page, knowing all + * committed content has been read, the ring buffer is empty. + */ + if (commit == reader) + return true; + + /* + * If writers are committing on a page other than reader page + * and head page, there should always be content to read. + */ + if (commit != head) + return false; + + /* + * Writers are committing on the head page, we just need + * to care about there're committed data, and the reader will + * swap reader page with head page when it is to read data. + */ + return rb_page_commit(commit) == 0; } /** |