From patchwork Wed Nov 6 22:00:31 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Begunkov X-Patchwork-Id: 11231241 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id ADCBC1747 for ; Wed, 6 Nov 2019 22:01:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 895142178F for ; Wed, 6 Nov 2019 22:01:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="NdwS0vWK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727498AbfKFWBF (ORCPT ); Wed, 6 Nov 2019 17:01:05 -0500 Received: from mail-wr1-f66.google.com ([209.85.221.66]:45984 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727109AbfKFWBE (ORCPT ); Wed, 6 Nov 2019 17:01:04 -0500 Received: by mail-wr1-f66.google.com with SMTP id h3so358243wrx.12; Wed, 06 Nov 2019 14:01:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=cjBwOeb8uc0MDJbK7bfIy9wsXovx5I/DEExGIwddhw0=; b=NdwS0vWKjCCVqCrvrHJ0NErzmoIQ6gfSUWyhGCWwSZ59H5nyORRnrHw8lO2aymdFwZ rFH+adVXaJydrXYlP16hJSfNqioKykjwlrpa+iM4QoE1t+YwOajr8RP7ojjVp+nEgjYO NyX/eZNXAEf7KIJyslPtib4aNDkDEc1xhwZ6MPBlnhDaVX+V42lHNxt3Wbj/Ydau2nI3 kTDL8ScMA8/ZT2AUuYFRHLONfuAXDJpZpBLwW0yR3EmRhryTvbfTTKOxhZ9xtgxpDBfc bdcS5aFXouHcdrsKkja2bK0IbPee+dt2foBmqBzCiS0HYzWqpjEyp6rlGw3iKXMcj6dB NUkw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=cjBwOeb8uc0MDJbK7bfIy9wsXovx5I/DEExGIwddhw0=; b=SetJIgICKuMFa+ViTi0OSMJlMqN8ibHu1TauPgLgIRrfCnBKOV1aCfw65NMS95+gNh c2AoDGN2i2s1XdazyKhYyI4Y8nK4ij5txfqLWc+UHDCAdJuyyls+o1/zq0RBuUHCajzy wmVErb9CCH8m6x6dF/1zze5/EiO35gm0KLUQcI4du3Vx+M540x5g2qzpzCl9Z5xJuY6K ySj/5H/qZfpio6aFNWmRflBLujHCiovecrgKgLP+5KK8/RvhEkZpK9CYf0WGaU2DwRy4 5/tUbgGG912UNSVCL+UqsrQXhu4Y11thkxp91FkeB9NKKA+sSwbeWZZMG2PJJDG3dBdK AlQw== X-Gm-Message-State: APjAAAU5u3uWP4HGOz2TalQdAIjzTyHGqi+4syyN4OWG0iDShCqnOfq2 lKWWulWM8nf4+g2FkUH5hrw= X-Google-Smtp-Source: APXvYqx2Zhw/zgEk4M+BDdHsG5T/mcQoTo26kYlctLBWpKDvfGvZlD1k0+2LwWTBP6ON+ZLjTCZGUw== X-Received: by 2002:a5d:660b:: with SMTP id n11mr4943196wru.146.1573077661887; Wed, 06 Nov 2019 14:01:01 -0800 (PST) Received: from localhost.localdomain ([109.126.141.164]) by smtp.gmail.com with ESMTPSA id c24sm62159wrb.27.2019.11.06.14.01.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 06 Nov 2019 14:01:01 -0800 (PST) From: Pavel Begunkov To: Jens Axboe , io-uring@vger.kernel.org, linux-block@vger.kernel.org Subject: [PATCH v2 2/3] io_uring: Use submit info inlined into req Date: Thu, 7 Nov 2019 01:00:31 +0300 Message-Id: X-Mailer: git-send-email 2.23.0 In-Reply-To: References: MIME-Version: 1.0 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Stack allocated struct sqe_submit is passed down to the submission path along with a request (a.k.a. struct io_kiocb), and will be copied into req->submit for async requests. As space for it is already allocated, fill req->submit in the first place instead of using on-stack one. As a result: 1. sqe->submit is the only place for sqe_submit and is always valid, so we don't need to track which one to use. 2. don't need to copy in case of async 3. allows to simplify the code by not carrying it as an argument all the way down 4. allows to reduce number of function arguments / potentially improve spilling The downside is that stack is most probably be cached, that's not true for just allocated memory for a request. Another concern is cache pollution. Though, a request would be touched and fetched along with req->submit at some point anyway, so shouldn't be a problem. Signed-off-by: Pavel Begunkov --- fs/io_uring.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 0289bb3cc697..f863304e451a 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2456,7 +2456,6 @@ static int __io_queue_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req, sqe_copy = kmemdup(s->sqe, sizeof(*sqe_copy), GFP_KERNEL); if (sqe_copy) { s->sqe = sqe_copy; - memcpy(&req->submit, s, sizeof(*s)); if (req->work.flags & IO_WQ_WORK_NEEDS_FILES) { ret = io_grab_files(ctx, req); if (ret) { @@ -2591,13 +2590,11 @@ static void io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req, } s->sqe = sqe_copy; - memcpy(&req->submit, s, sizeof(*s)); trace_io_uring_link(ctx, req, prev); list_add_tail(&req->list, &prev->link_list); } else if (s->sqe->flags & IOSQE_IO_LINK) { req->flags |= REQ_F_LINK; - memcpy(&req->submit, s, sizeof(*s)); INIT_LIST_HEAD(&req->link_list); *link = req; } else { @@ -2702,18 +2699,18 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr, } for (i = 0; i < nr; i++) { - struct sqe_submit s; struct io_kiocb *req; + unsigned int sqe_flags; req = io_get_req(ctx, statep); if (unlikely(!req)) break; - if (!io_get_sqring(ctx, &s)) { + if (!io_get_sqring(ctx, &req->submit)) { __io_free_req(req); break; } - if (io_sqe_needs_user(s.sqe) && !*mm) { + if (io_sqe_needs_user(req->submit.sqe) && !*mm) { mm_fault = mm_fault || !mmget_not_zero(ctx->sqo_mm); if (!mm_fault) { use_mm(ctx->sqo_mm); @@ -2721,7 +2718,9 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr, } } - if (link && (s.sqe->flags & IOSQE_IO_DRAIN)) { + sqe_flags = req->submit.sqe->flags; + + if (link && (sqe_flags & IOSQE_IO_DRAIN)) { if (!shadow_req) { shadow_req = io_get_req(ctx, NULL); if (unlikely(!shadow_req)) @@ -2729,24 +2728,25 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr, shadow_req->flags |= (REQ_F_IO_DRAIN | REQ_F_SHADOW_DRAIN); refcount_dec(&shadow_req->refs); } - shadow_req->sequence = s.sequence; + shadow_req->sequence = req->submit.sequence; } out: - s.ring_file = ring_file; - s.ring_fd = ring_fd; - s.has_user = *mm != NULL; - s.in_async = async; - s.needs_fixed_file = async; - trace_io_uring_submit_sqe(ctx, s.sqe->user_data, true, async); - io_submit_sqe(ctx, req, &s, statep, &link); + req->submit.ring_file = ring_file; + req->submit.ring_fd = ring_fd; + req->submit.has_user = *mm != NULL; + req->submit.in_async = async; + req->submit.needs_fixed_file = async; + trace_io_uring_submit_sqe(ctx, req->submit.sqe->user_data, + true, async); + io_submit_sqe(ctx, req, &req->submit, statep, &link); submitted++; /* * If previous wasn't linked and we have a linked command, * that's the end of the chain. Submit the previous link. */ - if (!(s.sqe->flags & IOSQE_IO_LINK) && link) { + if (!(sqe_flags & IOSQE_IO_LINK) && link) { io_queue_link_head(ctx, link, &link->submit, shadow_req); link = NULL; shadow_req = NULL;