[PATCH 5.4 126/154] ring-buffer: Fix bytes_dropped calculation issue

Greg Kroah-Hartman
2025-04-08T12:07:50Z

From: Feng Yang <yangfeng@kylinos.cn>

[ Upstream commit c73f0b69648501978e8b3e8fa7eef7f4197d0481 ]

The calculation of bytes-dropped and bytes_dropped_nested is reversed.
Although it does not affect the final calculation of total_dropped,
it should still be modified.

Link: https://lore.kernel.org/20250223070106.6781-1-yangfeng59949@163.com
Fixes: 6c43e554a2a5 ("ring-buffer: Add ring buffer startup selftest")
Signed-off-by: Feng Yang <yangfeng@kylinos.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
kernel/trace/ring_buffer.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 2011219c11a91..b12838d4c3270 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -5195,9 +5195,9 @@ static __init int rb_write_something(struct rb_test_data *data, bool nested)
/* Ignore dropped events before test starts. */
if (started) {
if (nested)
- data->bytes_dropped += len;
- else
data->bytes_dropped_nested += len;
+ else
+ data->bytes_dropped += len;
}
return len;
}
--
2.39.5