tracing: update file->f_pos when splice(2) it
Impact: Cleanup
These two lines:
if (unlikely(*ppos))
return -ESPIPE;
in tracing_buffers_splice_read() are not needed, VFS layer
has disabled seek(2).
We remove these two lines, and then we can update file->f_pos.
And tracing_buffers_read() updates file->f_pos, this fix
make tracing_buffers_splice_read() updates file->f_pos too.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <49D46670.4010503@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 8e189ff..9462976 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3428,13 +3428,6 @@
int size, i;
size_t ret;
- /*
- * We can't seek on a buffer input
- */
- if (unlikely(*ppos))
- return -ESPIPE;
-
-
for (i = 0; i < PIPE_BUFFERS && len; i++, len -= size) {
struct page *page;
int r;
@@ -3474,6 +3467,7 @@
spd.partial[i].offset = 0;
spd.partial[i].private = (unsigned long)ref;
spd.nr_pages++;
+ *ppos += size;
}
spd.nr_pages = i;