[PATCH v22 26/31] trace: Convert trace/seq to use copy_splice_read()

From: David Howells
Date: Mon May 22 2023 - 09:55:48 EST


For the splice from the trace seq buffer, just use copy_splice_read().

In the future, something better can probably be done by gifting pages from
seq->buf into the pipe, but that would require changing seq->buf into a
vmap over an array of pages.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Christoph Hellwig <hch@xxxxxx>
cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
cc: Jens Axboe <axboe@xxxxxxxxx>
cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
cc: linux-kernel@xxxxxxxxxxxxxxx
cc: linux-trace-kernel@xxxxxxxxxxxxxxx
cc: linux-fsdevel@xxxxxxxxxxxxxxx
cc: linux-block@xxxxxxxxxxxxxxx
cc: linux-mm@xxxxxxxxx
---
kernel/trace/trace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index ebc59781456a..c210d02fac97 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -5171,7 +5171,7 @@ static const struct file_operations tracing_fops = {
.open = tracing_open,
.read = seq_read,
.read_iter = seq_read_iter,
- .splice_read = generic_file_splice_read,
+ .splice_read = copy_splice_read,
.write = tracing_write_stub,
.llseek = tracing_lseek,
.release = tracing_release,