From fd14460cefe4d8b6069e7e10a62d24d51c300633 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Fri, 17 Jan 2020 03:57:59 +0300 Subject: [PATCH] io_uring: optimise use of ctx->drain_next Move setting ctx->drain_next to the only place it could be set, when it got linked non-head requests. The same for checking it, it's interesting only for a head of a link or a non-linked request. No functional changes here. This removes some code from the common path and also removes REQ_F_DRAIN_LINK flag, as it doesn't need it anymore. Signed-off-by: Pavel Begunkov Signed-off-by: Jens Axboe --- fs/io_uring.c | 41 +++++++++++++++++++++-------------------- 1 file changed, 21 insertions(+), 20 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 7715a729271a8..68843a1230003 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -506,7 +506,6 @@ struct io_kiocb { #define REQ_F_LINK 64 /* linked sqes */ #define REQ_F_LINK_TIMEOUT 128 /* has linked timeout */ #define REQ_F_FAIL_LINK 256 /* fail rest of links */ -#define REQ_F_DRAIN_LINK 512 /* link should be fully drained */ #define REQ_F_TIMEOUT 1024 /* timeout request */ #define REQ_F_ISREG 2048 /* regular file */ #define REQ_F_MUST_PUNT 4096 /* must be punted even for NONBLOCK */ @@ -4558,12 +4557,6 @@ static void io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe) { int ret; - if (unlikely(req->ctx->drain_next)) { - req->flags |= REQ_F_IO_DRAIN; - req->ctx->drain_next = 0; - } - req->ctx->drain_next = (req->flags & REQ_F_DRAIN_LINK) != 0; - ret = io_req_defer(req, sqe); if (ret) { if (ret != -EIOCBQUEUED) { @@ -4630,8 +4623,10 @@ err_req: if (*link) { struct io_kiocb *head = *link; - if (sqe_flags & IOSQE_IO_DRAIN) - head->flags |= REQ_F_DRAIN_LINK | REQ_F_IO_DRAIN; + if (sqe_flags & IOSQE_IO_DRAIN) { + head->flags |= REQ_F_IO_DRAIN; + ctx->drain_next = 1; + } if (sqe_flags & IOSQE_IO_HARDLINK) req->flags |= REQ_F_HARDLINK; @@ -4655,18 +4650,24 @@ err_req: io_queue_link_head(head); *link = NULL; } - } else if (sqe_flags & (IOSQE_IO_LINK|IOSQE_IO_HARDLINK)) { - req->flags |= REQ_F_LINK; - if (sqe_flags & IOSQE_IO_HARDLINK) - req->flags |= REQ_F_HARDLINK; - - INIT_LIST_HEAD(&req->link_list); - ret = io_req_defer_prep(req, sqe); - if (ret) - req->flags |= REQ_F_FAIL_LINK; - *link = req; } else { - io_queue_sqe(req, sqe); + if (unlikely(ctx->drain_next)) { + req->flags |= REQ_F_IO_DRAIN; + req->ctx->drain_next = 0; + } + if (sqe_flags & (IOSQE_IO_LINK|IOSQE_IO_HARDLINK)) { + req->flags |= REQ_F_LINK; + if (sqe_flags & IOSQE_IO_HARDLINK) + req->flags |= REQ_F_HARDLINK; + + INIT_LIST_HEAD(&req->link_list); + ret = io_req_defer_prep(req, sqe); + if (ret) + req->flags |= REQ_F_FAIL_LINK; + *link = req; + } else { + io_queue_sqe(req, sqe); + } } return true; -- 2.39.5