@@ -4032,6 +4032,9 @@ static int io_write(struct io_kiocb *req, unsigned int issue_flags)
if (ret2 != req->result && ret2 >= 0 && need_complete_io(req)) {
struct io_async_rw *rw;
+ trace_io_uring_short_write(req->ctx, kiocb->ki_pos - ret2,
+ req->result, ret2);
+
/* This is a partial write. The file pos has already been
* updated, setup the async struct to complete the request
* in the worker. Also update bytes_done to account for
@@ -543,6 +543,31 @@ TRACE_EVENT(io_uring_req_failed,
(unsigned long long) __entry->pad2, __entry->error)
);
+TRACE_EVENT(io_uring_short_write,
+
+ TP_PROTO(void *ctx, u64 fpos, u64 wanted, u64 got),
+
+ TP_ARGS(ctx, fpos, wanted, got),
+
+ TP_STRUCT__entry(
+ __field(void *, ctx)
+ __field(u64, fpos)
+ __field(u64, wanted)
+ __field(u64, got)
+ ),
+
+ TP_fast_assign(
+ __entry->ctx = ctx;
+ __entry->fpos = fpos;
+ __entry->wanted = wanted;
+ __entry->got = got;
+ ),
+
+ TP_printk("ring %p, fpos %lld, wanted %lld, got %lld",
+ __entry->ctx, __entry->fpos,
+ __entry->wanted, __entry->got)
+);
+
#endif /* _TRACE_IO_URING_H */
/* This part must be outside protection */
This adds the io_uring_short_write tracepoint to io_uring. A short write is issued if not all pages that are required for a write are in the page cache and the async buffered writes have to return EAGAIN. Signed-off-by: Stefan Roesch <shr@fb.com> --- fs/io_uring.c | 3 +++ include/trace/events/io_uring.h | 25 +++++++++++++++++++++++++ 2 files changed, 28 insertions(+)