From 1c849b481b3e4f8c36f297cd3aa88ef52a19cee9 Mon Sep 17 00:00:00 2001 From: Stefan Roesch Date: Thu, 16 Jun 2022 14:22:19 -0700 Subject: io_uring: Add tracepoint for short writes 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 Link: https://lore.kernel.org/r/20220616212221.2024518-13-shr@fb.com Signed-off-by: Jens Axboe --- include/trace/events/io_uring.h | 25 +++++++++++++++++++++++++ io_uring/rw.c | 3 +++ 2 files changed, 28 insertions(+) diff --git a/include/trace/events/io_uring.h b/include/trace/events/io_uring.h index 95a8cfaad15a..c5b21ff0ac85 100644 --- a/include/trace/events/io_uring.h +++ b/include/trace/events/io_uring.h @@ -630,6 +630,31 @@ TRACE_EVENT(io_uring_task_work_run, __entry->tctx, __entry->count, __entry->loops) ); +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 */ diff --git a/io_uring/rw.c b/io_uring/rw.c index 1f4a8ff98254..2b784795103c 100644 --- a/io_uring/rw.c +++ b/io_uring/rw.c @@ -933,6 +933,9 @@ int io_write(struct io_kiocb *req, unsigned int issue_flags) if (ret2 != req->cqe.res && ret2 >= 0 && need_complete_io(req)) { struct io_async_rw *rw; + trace_io_uring_short_write(req->ctx, kiocb->ki_pos - ret2, + req->cqe.res, 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 -- cgit