From patchwork Thu Sep 8 15:56:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Begunkov X-Patchwork-Id: 12970296 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E47C9C6FA86 for ; Thu, 8 Sep 2022 15:59:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231237AbiIHP7J (ORCPT ); Thu, 8 Sep 2022 11:59:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32880 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230407AbiIHP7G (ORCPT ); Thu, 8 Sep 2022 11:59:06 -0400 Received: from mail-ej1-x631.google.com (mail-ej1-x631.google.com [IPv6:2a00:1450:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 68F7DF827F for ; Thu, 8 Sep 2022 08:59:05 -0700 (PDT) Received: by mail-ej1-x631.google.com with SMTP id l14so15622663eja.7 for ; Thu, 08 Sep 2022 08:59:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date; bh=v9r22If6h69B1ae0T4+KgnzjvLRV9orbZ+tGlc/KePA=; b=liAwAX8RYVmIYFl6pJUImMIE+VXAw+4dzJsTJf1gNfbORPKRWuIBeWkBPO+55D7cMh kBJ8q5YwVjJC0al34icZSRvxrh2xFkBn6KLCUl2W3T32T2ncdJA/I1bzUWGq8sQ1azi0 hVe+ablw54+cytgjz6vinvq/TBu9ggpGdeFUJyJybQjB+K9u1XsYRmDTTLJjvJx7ZQTF i6cGG8p0lfPWVAxudV+ySR7GN/2p5ledFsg6yDuwJnDFHnzn5qeo6V2dicp5KU3ALuee rcHRXTUN9zi93X1R+tFZb90mORhMQZOPodtDKpLkyVALCWizipH38LtpnID8gGz3mQaI h2nQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date; bh=v9r22If6h69B1ae0T4+KgnzjvLRV9orbZ+tGlc/KePA=; b=RqKmOecGsqkEs0mLbWQNJiZ/TsSDU/yQX5wFenkkr+wL6PBjIjr3x6EriL/GC+Mpyg G9Wcof/Imh2b/dtj35AU67NEjfHRur+whnOhsfnNPC3j6b3n5LzTwNqm0UGj527YptHv vsG5ab73w+QHuop80m/ocynGq65ESm/8zivyHvzSKDXA/MYOuAKbHOOd7dhVBI1wHjZs xXuQnQvB+1iHcBgzK5tPMATB/NI/1hvCjO3M9XGSrsaDuTTn5dIsv+pUMraP3C5/ovqJ uW+O5ZnZ3OVTSccvo5v5f8ca45Ue4oOak2PaiOsGuGCi8p0VAZ9Inior7iz0cxLndOlI HHQg== X-Gm-Message-State: ACgBeo28dt8eE+nomE5Zs55wKzAa81nI0thKSELSLxqoKbONgu7Rwk1R cKy3EBP4ZLaIY7GQfdpLq95lry+gxRI= X-Google-Smtp-Source: AA6agR5p1ZvUb4chugFj7qMOaj7gPWy6tcbc/XUwuvKD+NYoAkJzE/QVCXD6LhxTNuUx86ndtArrhw== X-Received: by 2002:a17:907:94c2:b0:73d:c534:1ac0 with SMTP id dn2-20020a17090794c200b0073dc5341ac0mr6598776ejc.461.1662652743423; Thu, 08 Sep 2022 08:59:03 -0700 (PDT) Received: from 127.0.0.1localhost.com ([2620:10d:c092:600::2:cfb9]) by smtp.gmail.com with ESMTPSA id q26-20020a1709060e5a00b0073872f367cesm1392503eji.112.2022.09.08.08.59.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 08 Sep 2022 08:59:03 -0700 (PDT) From: Pavel Begunkov To: io-uring@vger.kernel.org Cc: Jens Axboe , asml.silence@gmail.com, Dylan Yudaken Subject: [PATCH 5/6] io_uring: add fast path for io_run_local_work() Date: Thu, 8 Sep 2022 16:56:56 +0100 Message-Id: X-Mailer: git-send-email 2.37.2 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org We'll grab uring_lock and call __io_run_local_work() with several atomics inside even if there are no task works. Skip it if ->work_llist is empty. Signed-off-by: Pavel Begunkov Reviewed-by: Dylan Yudaken --- io_uring/io_uring.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 2fb5f1e78fb2..85b795e4dc6a 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -1208,6 +1208,9 @@ int io_run_local_work(struct io_ring_ctx *ctx) bool locked; int ret; + if (llist_empty(&ctx->work_llist)) + return 0; + locked = mutex_trylock(&ctx->uring_lock); ret = __io_run_local_work(ctx, locked); if (locked)