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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9A562C54791 for ; Wed, 13 Mar 2024 15:19:22 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rkQNd-0000bS-2X; Wed, 13 Mar 2024 11:18:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rkQNV-0000XL-SS for qemu-devel@nongnu.org; Wed, 13 Mar 2024 11:18:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rkQNU-0000A9-2b for qemu-devel@nongnu.org; Wed, 13 Mar 2024 11:18:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1710343126; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=VEcRcqvX/jSNb5WHXXkOefOm59FO7Mwz4RJzG7a5dIA=; b=CC72/GFnnZyLi6HGyzZ6zITBgsluYlACVRwZIVAKPW9LQBW2r4AyvWd7H3+q+lRZntsbre PWWTpciLmCOo96VdqQ5q0bImWjXgWhRkBUuoqaJ8O+SY/RAhFf9tAcwyfw3Q9wRMJv4d1e qO2gQv8NpFraAxXdzbV4PW7+ucTha1Y= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-515-p4MHQAUkMNeec_dJf0Movw-1; Wed, 13 Mar 2024 11:18:41 -0400 X-MC-Unique: p4MHQAUkMNeec_dJf0Movw-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 93089882380; Wed, 13 Mar 2024 15:18:41 +0000 (UTC) Received: from localhost (unknown [10.39.192.186]) by smtp.corp.redhat.com (Postfix) with ESMTP id 09D33492BC9; Wed, 13 Mar 2024 15:18:40 +0000 (UTC) Date: Wed, 13 Mar 2024 11:18:39 -0400 From: Stefan Hajnoczi To: Prasad Pandit Cc: kwolf@redhat.com, qemu-block@nongnu.org, qemu-devel@nongnu.org, mtosatti@redhat.com, Prasad Pandit Subject: Re: [PATCH v3] linux-aio: add IO_CMD_FDSYNC command support Message-ID: <20240313151839.GA545171@fedora> References: <20240313084935.1412274-1-ppandit@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="3pj7XjJpTo2Dtv0N" Content-Disposition: inline In-Reply-To: <20240313084935.1412274-1-ppandit@redhat.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.9 Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.971, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org --3pj7XjJpTo2Dtv0N Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Mar 13, 2024 at 02:19:35PM +0530, Prasad Pandit wrote: > From: Prasad Pandit >=20 > Libaio defines IO_CMD_FDSYNC command to sync all outstanding > asynchronous I/O operations, by flushing out file data to the > disk storage. >=20 > Enable linux-aio to submit such aio request. This helps to > reduce latency induced via pthread_create calls by > thread-pool (aio=3Dthreads). >=20 > Signed-off-by: Prasad Pandit > --- > block/file-posix.c | 7 +++++++ > block/linux-aio.c | 22 +++++++++++++++++++++- > 2 files changed, 28 insertions(+), 1 deletion(-) >=20 > v3: check if host kernel supports aio_fsync call > -> https://lists.nongnu.org/archive/html/qemu-devel/2024-03/msg03210.ht= ml >=20 > diff --git a/block/file-posix.c b/block/file-posix.c > index 35684f7e21..a30494d1a8 100644 > --- a/block/file-posix.c > +++ b/block/file-posix.c > @@ -2453,6 +2453,8 @@ static inline bool raw_check_linux_io_uring(BDRVRaw= State *s) > #endif > =20 > #ifdef CONFIG_LINUX_AIO > +extern bool laio_has_fdsync(int); Please declare this in include/block/raw-aio.h alongside the other laio API= s. > + > static inline bool raw_check_linux_aio(BDRVRawState *s) > { > Error *local_err =3D NULL; > @@ -2599,6 +2601,11 @@ static int coroutine_fn raw_co_flush_to_disk(Block= DriverState *bs) > if (raw_check_linux_io_uring(s)) { > return luring_co_submit(bs, s->fd, 0, NULL, QEMU_AIO_FLUSH); > } > +#endif > +#ifdef CONFIG_LINUX_AIO > + if (raw_check_linux_aio(s) && laio_has_fdsync(s->fd)) { FDSYNC support should be probed at open() time and the result should be stored in a new bool field like s->laio_supports_fdsync. That way the cost of laio_has_fdsync() on every flush request is avoided. > + return laio_co_submit(s->fd, 0, NULL, QEMU_AIO_FLUSH, 0); > + } > #endif > return raw_thread_pool_submit(handle_aiocb_flush, &acb); > } > diff --git a/block/linux-aio.c b/block/linux-aio.c > index ec05d946f3..ed20a503e9 100644 > --- a/block/linux-aio.c > +++ b/block/linux-aio.c > @@ -67,6 +67,7 @@ struct LinuxAioState { > int event_max; > }; > =20 > +bool laio_has_fdsync(int); > static void ioq_submit(LinuxAioState *s); > =20 > static inline ssize_t io_event_ret(struct io_event *ev) > @@ -384,6 +385,9 @@ static int laio_do_submit(int fd, struct qemu_laiocb = *laiocb, off_t offset, > case QEMU_AIO_READ: > io_prep_preadv(iocbs, fd, qiov->iov, qiov->niov, offset); > break; > + case QEMU_AIO_FLUSH: > + io_prep_fdsync(iocbs, fd); > + break; > /* Currently Linux kernel does not support other operations */ > default: > fprintf(stderr, "%s: invalid AIO request type 0x%x.\n", > @@ -412,7 +416,7 @@ int coroutine_fn laio_co_submit(int fd, uint64_t offs= et, QEMUIOVector *qiov, > AioContext *ctx =3D qemu_get_current_aio_context(); > struct qemu_laiocb laiocb =3D { > .co =3D qemu_coroutine_self(), > - .nbytes =3D qiov->size, > + .nbytes =3D qiov ? qiov->size : 0, > .ctx =3D aio_get_linux_aio(ctx), > .ret =3D -EINPROGRESS, > .is_read =3D (type =3D=3D QEMU_AIO_READ), > @@ -486,3 +490,19 @@ void laio_cleanup(LinuxAioState *s) > } > g_free(s); > } > + > +bool laio_has_fdsync(int fd) > +{ > + struct iocb cb; > + struct iocb *cbs[] =3D {&cb, NULL}; > + > + io_context_t ctx =3D 0; > + io_setup(1, &ctx); > + > + /* check if host kernel supports IO_CMD_FDSYNC */ > + io_prep_fdsync(&cb, fd); > + int ret =3D io_submit(ctx, 1, cbs); > + > + io_destroy(ctx); > + return (ret =3D=3D -EINVAL) ? false : true; > +} > --=20 > 2.44.0 >=20 --3pj7XjJpTo2Dtv0N Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmXxw88ACgkQnKSrs4Gr c8j0NQf/VwFpzFlbG/Tvc2MT31vBtldKT7wUdmYOWL+YrYAw8X5EOL3MNB4zpQtF ia18/G8zHB+Y+9cdnH4zroxQkAM3uSdBlPibBhk8oEuAW/P/YOVgn1jmEiSLBK8N Kd1ZJJxGKBj9yJSMjYjZaOTop4Mn8+OPAV9qxD1VzpXEseJTzg+lKf/0zMc+zcuc 0Qyy8cE30SEG2aCFCpcd56SL/ni9ncjdN8o4r03knOTTlOX+OAIAO0aM1oNOlpHy 0xPIdsecW99quqh/4RpzWnRu6z9a0URa4g2/NEWFLzoW25tgd/lN9SxKCX9brCig bU3VxkjP7w67HcvOOVeak04rlnmwMQ== =VgQO -----END PGP SIGNATURE----- --3pj7XjJpTo2Dtv0N--