From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id EB5014619F; Wed, 5 Feb 2025 16:29:36 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id BFC9240289; Wed, 5 Feb 2025 16:29:36 +0100 (CET) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by mails.dpdk.org (Postfix) with ESMTP id 8242C40270 for ; Wed, 5 Feb 2025 16:29:35 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1738769375; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=HeS0vv9wEncZBQlVj/+fvBOEk3Ncn9X4MUr0RyGgmsg=; b=Zml1RTwYjArYSddF3PnDdF1uJfxFpbIZ26F+Vd01cCUJUmhcu1gm4TM9L7dmlUVAGhHYNP ONUpTnwCxvEdwgykaNa/B5kd7gsnLNox7IYhPwom4ITTQAtaRhUCqxa9F9NCsWg26DwNDc mCrt3amD5gBbb9qwnFQpiTgbPmGBzsk= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-128-EtyxytSzMtSx5ULnoD696g-1; Wed, 05 Feb 2025 10:29:32 -0500 X-MC-Unique: EtyxytSzMtSx5ULnoD696g-1 X-Mimecast-MFC-AGG-ID: EtyxytSzMtSx5ULnoD696g Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (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 mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id C262719560A7; Wed, 5 Feb 2025 15:29:30 +0000 (UTC) Received: from [10.39.208.34] (unknown [10.39.208.34]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7067C1800358; Wed, 5 Feb 2025 15:29:29 +0000 (UTC) Message-ID: <48f33e8b-8ba5-49f1-a38c-7e0f6efec30b@redhat.com> Date: Wed, 5 Feb 2025 16:29:26 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC 0/3] Vhost: fix FD entries cleanup To: Chenbo Xia , David Marchand Cc: "dev@dpdk.org" References: <20241224154958.146852-1-maxime.coquelin@redhat.com> <3EE665CF-8BD9-4F3E-8CF4-30F0A285A7CC@nvidia.com> From: Maxime Coquelin Autocrypt: addr=maxime.coquelin@redhat.com; keydata= xsFNBFOEQQIBEADjNLYZZqghYuWv1nlLisptPJp+TSxE/KuP7x47e1Gr5/oMDJ1OKNG8rlNg kLgBQUki3voWhUbMb69ybqdMUHOl21DGCj0BTU3lXwapYXOAnsh8q6RRM+deUpasyT+Jvf3a gU35dgZcomRh5HPmKMU4KfeA38cVUebsFec1HuJAWzOb/UdtQkYyZR4rbzw8SbsOemtMtwOx YdXodneQD7KuRU9IhJKiEfipwqk2pufm2VSGl570l5ANyWMA/XADNhcEXhpkZ1Iwj3TWO7XR uH4xfvPl8nBsLo/EbEI7fbuUULcAnHfowQslPUm6/yaGv6cT5160SPXT1t8U9QDO6aTSo59N jH519JS8oeKZB1n1eLDslCfBpIpWkW8ZElGkOGWAN0vmpLfdyiqBNNyS3eGAfMkJ6b1A24un /TKc6j2QxM0QK4yZGfAxDxtvDv9LFXec8ENJYsbiR6WHRHq7wXl/n8guyh5AuBNQ3LIK44x0 KjGXP1FJkUhUuruGyZsMrDLBRHYi+hhDAgRjqHgoXi5XGETA1PAiNBNnQwMf5aubt+mE2Q5r qLNTgwSo2dpTU3+mJ3y3KlsIfoaxYI7XNsPRXGnZi4hbxmeb2NSXgdCXhX3nELUNYm4ArKBP LugOIT/zRwk0H0+RVwL2zHdMO1Tht1UOFGfOZpvuBF60jhMzbQARAQABzSxNYXhpbWUgQ29x dWVsaW4gPG1heGltZS5jb3F1ZWxpbkByZWRoYXQuY29tPsLBeAQTAQIAIgUCV3u/5QIbAwYL CQgHAwIGFQgCCQoLBBYCAwECHgECF4AACgkQyjiNKEaHD4ma2g/+P+Hg9WkONPaY1J4AR7Uf kBneosS4NO3CRy0x4WYmUSLYMLx1I3VH6SVjqZ6uBoYy6Fs6TbF6SHNc7QbB6Qjo3neqnQR1 71Ua1MFvIob8vUEl3jAR/+oaE1UJKrxjWztpppQTukIk4oJOmXbL0nj3d8dA2QgHdTyttZ1H xzZJWWz6vqxCrUqHU7RSH9iWg9R2iuTzii4/vk1oi4Qz7y/q8ONOq6ffOy/t5xSZOMtZCspu Mll2Szzpc/trFO0pLH4LZZfz/nXh2uuUbk8qRIJBIjZH3ZQfACffgfNefLe2PxMqJZ8mFJXc RQO0ONZvwoOoHL6CcnFZp2i0P5ddduzwPdGsPq1bnIXnZqJSl3dUfh3xG5ArkliZ/++zGF1O wvpGvpIuOgLqjyCNNRoR7cP7y8F24gWE/HqJBXs1qzdj/5Hr68NVPV1Tu/l2D1KMOcL5sOrz 2jLXauqDWn1Okk9hkXAP7+0Cmi6QwAPuBT3i6t2e8UdtMtCE4sLesWS/XohnSFFscZR6Vaf3 gKdWiJ/fW64L6b9gjkWtHd4jAJBAIAx1JM6xcA1xMbAFsD8gA2oDBWogHGYcScY/4riDNKXi lw92d6IEHnSf6y7KJCKq8F+Jrj2BwRJiFKTJ6ChbOpyyR6nGTckzsLgday2KxBIyuh4w+hMq TGDSp2rmWGJjASrOwU0EVPSbkwEQAMkaNc084Qvql+XW+wcUIY+Dn9A2D1gMr2BVwdSfVDN7 0ZYxo9PvSkzh6eQmnZNQtl8WSHl3VG3IEDQzsMQ2ftZn2sxjcCadexrQQv3Lu60Tgj7YVYRM H+fLYt9W5YuWduJ+FPLbjIKynBf6JCRMWr75QAOhhhaI0tsie3eDsKQBA0w7WCuPiZiheJaL 4MDe9hcH4rM3ybnRW7K2dLszWNhHVoYSFlZGYh+MGpuODeQKDS035+4H2rEWgg+iaOwqD7bg CQXwTZ1kSrm8NxIRVD3MBtzp9SZdUHLfmBl/tLVwDSZvHZhhvJHC6Lj6VL4jPXF5K2+Nn/Su CQmEBisOmwnXZhhu8ulAZ7S2tcl94DCo60ReheDoPBU8PR2TLg8rS5f9w6mLYarvQWL7cDtT d2eX3Z6TggfNINr/RTFrrAd7NHl5h3OnlXj7PQ1f0kfufduOeCQddJN4gsQfxo/qvWVB7PaE 1WTIggPmWS+Xxijk7xG6x9McTdmGhYaPZBpAxewK8ypl5+yubVsE9yOOhKMVo9DoVCjh5To5 aph7CQWfQsV7cd9PfSJjI2lXI0dhEXhQ7lRCFpf3V3mD6CyrhpcJpV6XVGjxJvGUale7+IOp sQIbPKUHpB2F+ZUPWds9yyVxGwDxD8WLqKKy0WLIjkkSsOb9UBNzgRyzrEC9lgQ/ABEBAAHC wV8EGAECAAkFAlT0m5MCGwwACgkQyjiNKEaHD4nU8hAAtt0xFJAy0sOWqSmyxTc7FUcX+pbD KVyPlpl6urKKMk1XtVMUPuae/+UwvIt0urk1mXi6DnrAN50TmQqvdjcPTQ6uoZ8zjgGeASZg jj0/bJGhgUr9U7oG7Hh2F8vzpOqZrdd65MRkxmc7bWj1k81tOU2woR/Gy8xLzi0k0KUa8ueB iYOcZcIGTcs9CssVwQjYaXRoeT65LJnTxYZif2pfNxfINFzCGw42s3EtZFteczClKcVSJ1+L +QUY/J24x0/ocQX/M1PwtZbB4c/2Pg/t5FS+s6UB1Ce08xsJDcwyOPIH6O3tccZuriHgvqKP yKz/Ble76+NFlTK1mpUlfM7PVhD5XzrDUEHWRTeTJSvJ8TIPL4uyfzhjHhlkCU0mw7Pscyxn DE8G0UYMEaNgaZap8dcGMYH/96EfE5s/nTX0M6MXV0yots7U2BDb4soLCxLOJz4tAFDtNFtA wLBhXRSvWhdBJZiig/9CG3dXmKfi2H+wdUCSvEFHRpgo7GK8/Kh3vGhgKmnnxhl8ACBaGy9n fxjSxjSO6rj4/MeenmlJw1yebzkX8ZmaSi8BHe+n6jTGEFNrbiOdWpJgc5yHIZZnwXaW54QT UhhSjDL1rV2B4F28w30jYmlRmm2RdN7iCZfbyP3dvFQTzQ4ySquuPkIGcOOHrvZzxbRjzMx1 Mwqu3GQ= In-Reply-To: <3EE665CF-8BD9-4F3E-8CF4-30F0A285A7CC@nvidia.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: EsFuv1YXqIip5eLbrdhvw5deJTI2t1IAMs6qbiESUqE_1738769371 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Hi Chenbo & David, On 2/5/25 8:27 AM, Chenbo Xia wrote: > Hi David, > >> On Feb 4, 2025, at 21:18, David Marchand wrote: >> >> External email: Use caution opening links or attachments >> >> >> Hello vhost maintainers, >> >> On Tue, Dec 24, 2024 at 4:50 PM Maxime Coquelin >> wrote: >>> >>> The vhost FD manager provides a way for the read/write >>> callbacks to request removal of their associated FD from >>> the epoll FD set. Problem is that it is missing a cleanup >>> callback, so the read/write callback requesting the removal >>> have to perform cleanups before the FD is removed from the >>> FD set. It includes closing the FD before it is removed >>> from the epoll FD set. >>> >>> This series introduces a new cleanup callback which, if >>> implemented, is closed right after the FD is removed from >>> FD set. >>> >>> Maxime Coquelin (3): >>> vhost: add cleanup callback to FD entries >>> vhost: fix vhost-user socket cleanup order >>> vhost: improve VDUSE reconnect handler cleanup >>> >>> lib/vhost/fd_man.c | 16 ++++++++++++---- >>> lib/vhost/fd_man.h | 3 ++- >>> lib/vhost/socket.c | 46 ++++++++++++++++++++++++++-------------------- >>> lib/vhost/vduse.c | 16 +++++++++++----- >>> 4 files changed, 51 insertions(+), 30 deletions(-) >> >> I tried this series, and it fixes the error log I reported. >> >> On the other hand, I wonder if we could do something simpler. >> >> The fd is only used by the registered handlers. >> If a handler reports that it does not want to watch this fd anymore, >> then there is no remaining user in the vhost library for this fd. >> >> So my proposal would be to rename the "remove" flag as a "close" flag: >> >> @@ -12,7 +12,7 @@ struct fdset; >> >> #define MAX_FDS 1024 >> >> -typedef void (*fd_cb)(int fd, void *dat, int *remove); >> +typedef void (*fd_cb)(int fd, void *dat, int *close); >> >> struct fdset *fdset_init(const char *name); >> >> And defer closing to fd_man. >> Something like: >> >> @@ -367,9 +367,9 @@ fdset_event_dispatch(void *arg) >> pthread_mutex_unlock(&pfdset->fd_mutex); >> >> if (rcb && events[i].events & (EPOLLIN | >> EPOLLERR | EPOLLHUP)) >> - rcb(fd, dat, &remove1); >> + rcb(fd, dat, &close1); >> if (wcb && events[i].events & (EPOLLOUT | >> EPOLLERR | EPOLLHUP)) >> - wcb(fd, dat, &remove2); >> + wcb(fd, dat, &close2); >> pfdentry->busy = 0; >> /* >> * fdset_del needs to check busy flag. >> @@ -381,8 +381,10 @@ fdset_event_dispatch(void *arg) >> * fdentry not to be busy, so we can't call >> * fdset_del_locked(). >> */ >> - if (remove1 || remove2) >> + if (close1 || close2) { >> fdset_del(pfdset, fd); >> + close(fd); >> + } >> } >> >> if (pfdset->destroy) >> >> >> And the only thing to move out of the socket and vduse handlers is the >> close(fd) call. >> >> Like: >> >> @@ -303,7 +303,7 @@ vhost_user_server_new_connection(int fd, void >> *dat, int *remove __rte_unused) >> } >> >> static void >> -vhost_user_read_cb(int connfd, void *dat, int *remove) >> +vhost_user_read_cb(int connfd, void *dat, int *close) >> { >> struct vhost_user_connection *conn = dat; >> struct vhost_user_socket *vsocket = conn->vsocket; >> @@ -313,8 +313,7 @@ vhost_user_read_cb(int connfd, void *dat, int *remove) >> if (ret < 0) { >> struct virtio_net *dev = get_device(conn->vid); >> >> - close(connfd); >> - *remove = 1; >> + *close = 1; > > I have one concern here is compared with this RFC, the proposal changed the timing > of close connfd，which means on QEMU side, cleaning up resources will happen later. > > Currently I can’t think of issues could be introduced by this change (maybe you and > Maxime could remind me of something :) That's a good point. I just tested David's suggestion with Vhost-user with OVS and QEMU: - guest shutdown + reconnect - live-migration - OVS restart It seems to behave very well. > Besides this, definitely this proposal is cleaner. I agree, I will send a new revision re-using David's proposal. Thanks, Maxime > > Thanks, > Chenbo > >> >> if (dev) >> vhost_destroy_device_notify(dev); >> >> >> Maxime, Chenbo, opinions? >> >> >> -- >> David Marchand >> >