From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6DE1DC433E0 for ; Mon, 25 Jan 2021 12:12:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1576B22C9E for ; Mon, 25 Jan 2021 12:12:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727830AbhAYMKx (ORCPT ); Mon, 25 Jan 2021 07:10:53 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42870 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727782AbhAYMKU (ORCPT ); Mon, 25 Jan 2021 07:10:20 -0500 Received: from mail-wr1-x436.google.com (mail-wr1-x436.google.com [IPv6:2a00:1450:4864:20::436]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 929F2C0611C3 for ; Mon, 25 Jan 2021 03:46:20 -0800 (PST) Received: by mail-wr1-x436.google.com with SMTP id h9so1798306wrr.9 for ; Mon, 25 Jan 2021 03:46:20 -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=RwFviHiQikljVa9q/UTl1Bb7vNvtLuFAVTzKv8c7E2U=; b=eMjiPbRYLZbmgRXb8BuxkP23SdGgv0OZtbWTN/5a1qDYaFypXtp4JFosajYlDJumwu 6B6jV+Kuf9zX9QVYVra4212xwIIJkrO4Vky4sNOHw7VUT59NxQYvfzhGo+OX+Rni2P3Q v5cJncO/+mxUCfXSEqi2Czgzwlsa/N+M+x/YLnOklCpwqJ5I64UNrieiCz+GAU9QWBks b4NM84WgAVOMiRxGefBT0Y3HOBjPEK0U5QoOSVAEZl0+l3tetX5CNfmlS/3k00EPvQQe C+DD2kHRjlGb9v1lh4QCVL3d0E8EDuJFTJZAKYJXv83Fdy9x/7mFq/wf5+T15NCFwzQp f0YQ== 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=RwFviHiQikljVa9q/UTl1Bb7vNvtLuFAVTzKv8c7E2U=; b=MkEX2F1tn5rwWFLKqma5rRkGkWO+9ZzQxnGGfE1lwJIFgAdbjWZ4hmyYMOg+lDGTSo 9DypZ9bSupD2xxept4epAvmavDsLjH8fY5jB8AVHt0NHfE+tCb040K4b9jpn3+mxsDKl lstnmIeEDRWgjwmOcvzUWZ60SmrCpYv27NPJBVUKDNYKeTGAd0fnSgUGDOM/KMDfOV1d 8ZhWNnbqcqsnbotKSUpEUyKPsBrwd/kDIuwFGCXWCNxwN88xnKSvDCcyRqjdTQlKLABM be5aqLXJv4Fw9woK6KeObM1RvwzZqO7jOp5j4n29QYVOtToO0bRTxtnuTAZHyMirMYmW 2uEw== X-Gm-Message-State: AOAM532u1nHZEB+HX0wWCVHHJwvGysnGC1QYkuf0BUDUSqlFBCIGbjSa 41pgcVK+46h7O95anVsMMuV7DKsc/1A= X-Google-Smtp-Source: ABdhPJzPOz4bbce8gZfGB0x9+cyS1kEuakP6tTYadqIAYty5TJIGrzY9J38SZnI4EehRxV95Gxa/yg== X-Received: by 2002:a5d:420d:: with SMTP id n13mr499649wrq.320.1611575179410; Mon, 25 Jan 2021 03:46:19 -0800 (PST) Received: from localhost.localdomain ([85.255.234.11]) by smtp.gmail.com with ESMTPSA id a6sm12571433wru.66.2021.01.25.03.46.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Jan 2021 03:46:18 -0800 (PST) From: Pavel Begunkov To: Jens Axboe , io-uring@vger.kernel.org Subject: [PATCH 6/8] io_uring: replace list with array for compl batch Date: Mon, 25 Jan 2021 11:42:25 +0000 Message-Id: X-Mailer: git-send-email 2.24.0 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Reincarnation of an old patch that replaces a list in struct io_compl_batch with an array. It's needed to avoid hooking requests via their compl.list, because it won't be always available in the future. It's also nice to split io_submit_flush_completions() to avoid free under locks and remove unlock/lock with a long comment describing when it can be done. Signed-off-by: Pavel Begunkov --- fs/io_uring.c | 35 +++++++++++------------------------ 1 file changed, 11 insertions(+), 24 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 08d0c8b60c2a..fcd8df43b6bf 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -260,10 +260,11 @@ struct io_sq_data { }; #define IO_IOPOLL_BATCH 8 +#define IO_COMPL_BATCH 32 struct io_comp_state { unsigned int nr; - struct list_head list; + struct io_kiocb *reqs[IO_COMPL_BATCH]; }; struct io_submit_state { @@ -1338,7 +1339,6 @@ static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) init_llist_head(&ctx->rsrc_put_llist); submit_state = &ctx->submit_state; - INIT_LIST_HEAD(&submit_state->comp.list); submit_state->comp.nr = 0; submit_state->file_refs = 0; submit_state->free_reqs = 0; @@ -1901,33 +1901,20 @@ static void io_req_complete_nostate(struct io_kiocb *req, long res, static void io_submit_flush_completions(struct io_comp_state *cs, struct io_ring_ctx *ctx) { + int i, nr = cs->nr; + spin_lock_irq(&ctx->completion_lock); - while (!list_empty(&cs->list)) { - struct io_kiocb *req; + for (i = 0; i < nr; i++) { + struct io_kiocb *req = cs->reqs[i]; - req = list_first_entry(&cs->list, struct io_kiocb, compl.list); - list_del(&req->compl.list); __io_cqring_fill_event(req, req->result, req->compl.cflags); - - /* - * io_free_req() doesn't care about completion_lock unless one - * of these flags is set. REQ_F_WORK_INITIALIZED is in the list - * because of a potential deadlock with req->work.fs->lock - * We defer both, completion and submission refs. - */ - if (req->flags & (REQ_F_FAIL_LINK|REQ_F_LINK_TIMEOUT - |REQ_F_WORK_INITIALIZED)) { - spin_unlock_irq(&ctx->completion_lock); - io_double_put_req(req); - spin_lock_irq(&ctx->completion_lock); - } else { - io_double_put_req(req); - } } io_commit_cqring(ctx); spin_unlock_irq(&ctx->completion_lock); io_cqring_ev_posted(ctx); + for (i = 0; i < nr; i++) + io_double_put_req(cs->reqs[i]); cs->nr = 0; } @@ -6565,8 +6552,8 @@ static void __io_queue_sqe(struct io_kiocb *req, struct io_comp_state *cs) } else if (likely(!ret)) { /* drop submission reference */ if (req->flags & REQ_F_COMPLETE_INLINE) { - list_add_tail(&req->compl.list, &cs->list); - if (++cs->nr >= 32) + cs->reqs[cs->nr++] = req; + if (cs->nr == IO_COMPL_BATCH) io_submit_flush_completions(cs, req->ctx); req = NULL; } else { @@ -6705,7 +6692,7 @@ static int io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, static void io_submit_state_end(struct io_submit_state *state, struct io_ring_ctx *ctx) { - if (!list_empty(&state->comp.list)) + if (state->comp.nr) io_submit_flush_completions(&state->comp, ctx); if (state->plug_started) blk_finish_plug(&state->plug); -- 2.24.0