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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A8DCC433EF for ; Sat, 16 Oct 2021 23:26:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5B05260F8F for ; Sat, 16 Oct 2021 23:26:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241203AbhJPX2O (ORCPT ); Sat, 16 Oct 2021 19:28:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40100 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241073AbhJPX2M (ORCPT ); Sat, 16 Oct 2021 19:28:12 -0400 Received: from mail-ed1-x533.google.com (mail-ed1-x533.google.com [IPv6:2a00:1450:4864:20::533]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 59E8CC061765 for ; Sat, 16 Oct 2021 16:26:03 -0700 (PDT) Received: by mail-ed1-x533.google.com with SMTP id ec8so54079832edb.6 for ; Sat, 16 Oct 2021 16:26:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:content-language:to:cc :references:from:subject:in-reply-to:content-transfer-encoding; bh=oLDt9YO0peltku8K38kIEtLG2pmoKcgOtOdF1celThM=; b=gCOAqEBwBfSEmLi8txbmsXjPXF5pjRR4z09AtCUwuDgIm8zSHAABZRnSWcPfSzKbq0 voXMEsOfHhtUtR6IrQwCCncuWj8CywvNfpIwj5yv71P29zXGbj8Zv5tonicsWxKIhldB FBMON73FVjUrjZ1ZRawr/+2/ofQlBGNoir62S45Xh8Zc3UcUjgPhvpy0QuSlSUbFFqMT FPz2nGcIC95cPcAi5yfcYmqbWdHBry2te5HD2dNyCaiZSriXnhn9tw4FsEJcl973t5Ck KCt2lWved3HfN2NpPdnPccyMblwC1TE2VKQKIyjTGnopeejWQPZXlrhOEjI9+iEGLjh9 VAPA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent :content-language:to:cc:references:from:subject:in-reply-to :content-transfer-encoding; bh=oLDt9YO0peltku8K38kIEtLG2pmoKcgOtOdF1celThM=; b=r2wAly3OEzNI3aJGxZ+VjjQbBJH/ot9ZrzBC/ljbAZdlAGzpPH5flh4pFig9Nm/F5W tdTDoPOKXupTFo6/T9gOd2PqUiEW9seljqBe3hyKNHCZnboUVlcK/cSAVRdIXn5w5Q9V 3NK2w+E9Ah/+Wiv3z0DRKyct5vVdGKyvYFYfpx/hXEEYmH8NsKWYFN1FVvk1y+QZycap JGkl0u19COEV/CE6x3nvsWf2uP2RhKGXa4LFEy0tuo7uXZOSEQ5MKDSLPEdSMXvcC2dW B3e5XqSp8vYm8ByZB31rq/ifYWv2pZzGFDjAcfCbZgUwpVEyuR3p63ivtQBrRBEcpfbo LULw== X-Gm-Message-State: AOAM532dU4xrK3kl1d//Un2/4tcmbhrD8EqqXV74DpCbOb6SdGcAPXPE s3QzeWwKcKFGi2LwzzwisCg= X-Google-Smtp-Source: ABdhPJy4+RIljhCAwJan/m8cEVyn0kowbMHJH3f5+2kM3eZtcFC1Ee2CnmBmeeaSIdGOBmmOVRIHnw== X-Received: by 2002:a17:907:75f5:: with SMTP id jz21mr17915575ejc.345.1634426761905; Sat, 16 Oct 2021 16:26:01 -0700 (PDT) Received: from [192.168.8.197] ([185.69.145.201]) by smtp.gmail.com with ESMTPSA id oz11sm6586239ejc.72.2021.10.16.16.26.01 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 16 Oct 2021 16:26:01 -0700 (PDT) Message-ID: <869d5110-973b-6c70-604d-48d6108c0379@gmail.com> Date: Sun, 17 Oct 2021 00:25:22 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.1.2 Content-Language: en-US To: Noah Goldstein Cc: "open list:IO_URING" , Jens Axboe References: <2c2536c5896d70994de76e387ea09a0402173a3f.1634144845.git.asml.silence@gmail.com> From: Pavel Begunkov Subject: Re: [PATCH 8/8] io_uring: rearrange io_read()/write() In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 10/16/21 23:52, Noah Goldstein wrote: > On Thu, Oct 14, 2021 at 10:13 AM Pavel Begunkov wrote: >> - /* If the file doesn't support async, just async punt */ >> - if (force_nonblock && !io_file_supports_nowait(req, WRITE)) >> - goto copy_iov; >> + /* file path doesn't support NOWAIT for non-direct_IO */ >> + if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) && > > You can drop this 'force_nonblock' no? Indeed > >> + (req->flags & REQ_F_ISREG)) >> + goto copy_iov; >> >> - /* file path doesn't support NOWAIT for non-direct_IO */ >> - if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) && >> - (req->flags & REQ_F_ISREG)) >> - goto copy_iov; >> + kiocb->ki_flags |= IOCB_NOWAIT; >> + } else { >> + /* Ensure we clear previously set non-block flag */ >> + kiocb->ki_flags &= ~IOCB_NOWAIT; >> + } >> >> ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), req->result); >> if (unlikely(ret)) > > ... > > What swapping order of conditions below: > if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN) > > The ret2 check will almost certainly be faster than 2x deref. Makes sense. Want to send a patch? -- Pavel Begunkov