[PATCH v21 4/9] ring-buffer: Show commit numbers in buffer_meta file
From: Steven Rostedt <rostedt@kernel.org>
Date: 2026-05-22 17:10:27
Also in:
lkml
Subsystem:
the rest, tracing · Maintainers:
Linus Torvalds, Steven Rostedt, Masami Hiramatsu
From: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> In addition to the index number, show the commit numbers of each data page in the per_cpu buffer_meta file. This is useful for understanding the current status of the persistent ring buffer. (Note that this file is shown only for persistent ring buffer and its backup instance) Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> --- kernel/trace/ring_buffer.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index dc603d9c9414..88e613e78632 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c@@ -2231,6 +2231,7 @@ static int rbm_show(struct seq_file *m, void *v) struct ring_buffer_per_cpu *cpu_buffer = m->private; struct ring_buffer_cpu_meta *meta = cpu_buffer->ring_meta; unsigned long val = (unsigned long)v; + struct buffer_data_page *dpage; if (val == 1) { seq_printf(m, "head_buffer: %d\n",
@@ -2243,7 +2244,9 @@ static int rbm_show(struct seq_file *m, void *v) } val -= 2; - seq_printf(m, "buffer[%ld]: %d\n", val, meta->buffers[val]); + dpage = rb_range_buffer(cpu_buffer, val); + seq_printf(m, "buffer[%ld]: %d (commit: %ld)\n", + val, meta->buffers[val], dpage ? local_read(&dpage->commit) : -1); return 0; }
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2.53.0