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Sun, 8 May 2022 15:32:17 +0000 Received: from SG2PR01MB2411.apcprd01.prod.exchangelabs.com ([fe80::f50a:7a05:5565:fda2]) by SG2PR01MB2411.apcprd01.prod.exchangelabs.com ([fe80::f50a:7a05:5565:fda2%5]) with mapi id 15.20.5227.023; Sun, 8 May 2022 15:32:17 +0000 From: Hao Xu To: io-uring@vger.kernel.org Cc: Jens Axboe , Pavel Begunkov Subject: [PATCH 4/4] io_uring: implement multishot mode for accept Date: Sun, 8 May 2022 23:32:03 +0800 Message-ID: X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220508153203.5544-1-haoxu.linux@gmail.com> References: <20220508153203.5544-1-haoxu.linux@gmail.com> Content-Transfer-Encoding: 8bit Content-Type: text/plain X-TMN: [2gYRLntLoMy68tBtpK6luDs+dwdPP2ag] X-ClientProxiedBy: HK2PR04CA0051.apcprd04.prod.outlook.com (2603:1096:202:14::19) To SG2PR01MB2411.apcprd01.prod.exchangelabs.com (2603:1096:4:4f::14) X-Microsoft-Original-Message-ID: <20220508153203.5544-5-haoxu.linux@gmail.com> MIME-Version: 1.0 Sender: Hao Xu X-MS-Exchange-MessageSentRepresentingType: 2 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: db8bec4c-1a77-4abd-a5e1-08da3107ee49 X-MS-TrafficTypeDiagnostic: TY2PR0101MB3104:EE_ X-Microsoft-Antispam: BCL:0; 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Then the client will read the data and then close the connection. Here I test 10000 clients connect one server, data size 128 bytes. And each client has a go routine for it, so they come to the server in short time. test 20 times before/after this patchset, time spent:(unit cycle, which is the return value of clock()) before: 1930136+1940725+1907981+1947601+1923812+1928226+1911087+1905897+1941075 +1934374+1906614+1912504+1949110+1908790+1909951+1941672+1969525+1934984 +1934226+1914385)/20.0 = 1927633.75 after: 1858905+1917104+1895455+1963963+1892706+1889208+1874175+1904753+1874112 +1874985+1882706+1884642+1864694+1906508+1916150+1924250+1869060+1889506 +1871324+1940803)/20.0 = 1894750.45 (1927633.75 - 1894750.45) / 1927633.75 = 1.65% Signed-off-by: Hao Xu --- fs/io_uring.c | 42 +++++++++++++++++++++++++++++++++++++----- 1 file changed, 37 insertions(+), 5 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index e0d12af04cd1..f21172913336 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1146,6 +1146,7 @@ static const struct io_op_def io_op_defs[] = { .unbound_nonreg_file = 1, .pollin = 1, .poll_exclusive = 1, + .ioprio = 1, /* used for flags */ }, [IORING_OP_ASYNC_CANCEL] = { .audit_skip = 1, @@ -5706,6 +5707,7 @@ static int io_recv(struct io_kiocb *req, unsigned int issue_flags) static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_accept *accept = &req->accept; + unsigned flags; if (sqe->len || sqe->buf_index) return -EINVAL; @@ -5714,19 +5716,26 @@ static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2)); accept->flags = READ_ONCE(sqe->accept_flags); accept->nofile = rlimit(RLIMIT_NOFILE); + flags = READ_ONCE(sqe->ioprio); + if (flags & ~IORING_ACCEPT_MULTISHOT) + return -EINVAL; accept->file_slot = READ_ONCE(sqe->file_index); - if (accept->file_slot && (accept->flags & SOCK_CLOEXEC)) + if (accept->file_slot && ((accept->flags & SOCK_CLOEXEC) || + flags & IORING_ACCEPT_MULTISHOT)) return -EINVAL; if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK)) return -EINVAL; if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK)) accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK; + if (flags & IORING_ACCEPT_MULTISHOT) + req->flags |= REQ_F_APOLL_MULTISHOT; return 0; } static int io_accept(struct io_kiocb *req, unsigned int issue_flags) { + struct io_ring_ctx *ctx = req->ctx; struct io_accept *accept = &req->accept; bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0; @@ -5734,6 +5743,7 @@ static int io_accept(struct io_kiocb *req, unsigned int issue_flags) struct file *file; int ret, fd; +retry: if (!fixed) { fd = __get_unused_fd_flags(accept->flags, accept->nofile); if (unlikely(fd < 0)) @@ -5745,8 +5755,12 @@ static int io_accept(struct io_kiocb *req, unsigned int issue_flags) if (!fixed) put_unused_fd(fd); ret = PTR_ERR(file); - if (ret == -EAGAIN && force_nonblock) - return -EAGAIN; + if (ret == -EAGAIN && force_nonblock) { + if ((req->flags & IO_APOLL_MULTI_POLLED) == + IO_APOLL_MULTI_POLLED) + ret = 0; + return ret; + } if (ret == -ERESTARTSYS) ret = -EINTR; req_set_fail(req); @@ -5757,8 +5771,26 @@ static int io_accept(struct io_kiocb *req, unsigned int issue_flags) ret = io_install_fixed_file(req, file, issue_flags, accept->file_slot - 1); } - __io_req_complete(req, issue_flags, ret, 0); - return 0; + + if (!(req->flags & REQ_F_APOLL_MULTISHOT)) { + __io_req_complete(req, issue_flags, ret, 0); + return 0; + } + if (ret >= 0) { + bool filled; + + spin_lock(&ctx->completion_lock); + filled = io_fill_cqe_aux(ctx, req->cqe.user_data, ret, + IORING_CQE_F_MORE); + io_commit_cqring(ctx); + spin_unlock(&ctx->completion_lock); + if (!filled) + return -ECANCELED; + io_cqring_ev_posted(ctx); + goto retry; + } + + return ret; } static int io_connect_prep_async(struct io_kiocb *req) -- 2.25.1