From patchwork Tue Dec 5 06:48:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arseniy Krasnov X-Patchwork-Id: 13479465 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=salutedevices.com header.i=@salutedevices.com header.b="HO6bmvvR" Received: from mx1.sberdevices.ru (mx2.sberdevices.ru [45.89.224.132]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1F9BE116; Mon, 4 Dec 2023 22:56:33 -0800 (PST) Received: from p-infra-ksmg-sc-msk02 (localhost [127.0.0.1]) by mx1.sberdevices.ru (Postfix) with ESMTP id 61C7A120021; Tue, 5 Dec 2023 09:56:29 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.sberdevices.ru 61C7A120021 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=salutedevices.com; s=mail; t=1701759389; bh=izyPkWgOH/PKLqqgIrJIIPmLvVHmTElrER66eD1o/RA=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type:From; b=HO6bmvvR++UiZ/lG/iAvqEKY2T2AADiCeT6CPfNgkdVW7Y7aSbYzrDFLUcTXGVhTY v9Sr5kG2W/kkUiK7ce+SpZraKr7ICiVi/ZlM8OigL2a/lPDkLJbKPW1ShaejSfhgk9 h4cKD4Sioio7dUITkvB2A7AsJu06WtQ5nUcaLeJbtCyjUSkJVjrjlOzPxepeqwnFy0 Pf4XgkGE+g0cSdlh4EPmN79yHkTolcrHoDhvUeQkqGqcUEQ2uR0HmDjHfhoxC1sx9d jEX2BqCVmACcQcXe3Y9XU5vO+FT6IHo2AvvIoF7TDlWyzPrtg2BANvuAbGrUd/8HrQ 4nk/4aD8cAaLg== Received: from p-i-exch-sc-m01.sberdevices.ru (p-i-exch-sc-m01.sberdevices.ru [172.16.192.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.sberdevices.ru (Postfix) with ESMTPS; Tue, 5 Dec 2023 09:56:28 +0300 (MSK) Received: from localhost.localdomain (100.64.160.123) by p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.40; Tue, 5 Dec 2023 09:56:28 +0300 From: Arseniy Krasnov To: Stefan Hajnoczi , Stefano Garzarella , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "Michael S. Tsirkin" , Jason Wang , Bobby Eshleman CC: , , , , , , Subject: [PATCH net-next v6 0/4] send credit update during setting SO_RCVLOWAT Date: Tue, 5 Dec 2023 09:48:02 +0300 Message-ID: <20231205064806.2851305-1-avkrasnov@salutedevices.com> X-Mailer: git-send-email 2.35.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: p-i-exch-sc-m02.sberdevices.ru (172.16.192.103) To p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) X-KSMG-Rule-ID: 10 X-KSMG-Message-Action: clean X-KSMG-AntiSpam-Lua-Profiles: 181836 [Dec 05 2023] X-KSMG-AntiSpam-Version: 6.0.0.2 X-KSMG-AntiSpam-Envelope-From: avkrasnov@salutedevices.com X-KSMG-AntiSpam-Rate: 0 X-KSMG-AntiSpam-Status: not_detected X-KSMG-AntiSpam-Method: none X-KSMG-AntiSpam-Auth: dkim=none X-KSMG-AntiSpam-Info: LuaCore: 5 0.3.5 98d108ddd984cca1d7e65e595eac546a62b0144b, {Tracking_uf_ne_domains}, {Tracking_from_domain_doesnt_match_to}, d41d8cd98f00b204e9800998ecf8427e.com:7.1.1;salutedevices.com:7.1.1;127.0.0.199:7.1.2;p-i-exch-sc-m01.sberdevices.ru:7.1.1,5.0.1;100.64.160.123:7.1.2;lore.kernel.org:7.1.1;git.kernel.org:7.1.1, FromAlignment: s, ApMailHostAddress: 100.64.160.123 X-MS-Exchange-Organization-SCL: -1 X-KSMG-AntiSpam-Interceptor-Info: scan successful X-KSMG-AntiPhishing: Clean, bases: 2023/12/05 03:34:00 X-KSMG-LinksScanning: Clean, bases: 2023/12/05 03:34:00 X-KSMG-AntiVirus: Kaspersky Secure Mail Gateway, version 2.0.1.6960, bases: 2023/12/05 03:59:00 #22607474 X-KSMG-AntiVirus-Status: Clean, skipped X-Patchwork-Delegate: kuba@kernel.org Hello, DESCRIPTION This patchset fixes old problem with hungup of both rx/tx sides and adds test for it. This happens due to non-default SO_RCVLOWAT value and deferred credit update in virtio/vsock. Link to previous old patchset: https://lore.kernel.org/netdev/39b2e9fd-601b-189d-39a9-914e5574524c@sberdevices.ru/ Here is what happens step by step: TEST INITIAL CONDITIONS 1) Vsock buffer size is 128KB. 2) Maximum packet size is also 64KB as defined in header (yes it is hardcoded, just to remind about that value). 3) SO_RCVLOWAT is default, e.g. 1 byte. STEPS SENDER RECEIVER 1) sends 128KB + 1 byte in a single buffer. 128KB will be sent, but for 1 byte sender will wait for free space at peer. Sender goes to sleep. 2) reads 64KB, credit update not sent 3) sets SO_RCVLOWAT to 64KB + 1 4) poll() -> wait forever, there is only 64KB available to read. So in step 4) receiver also goes to sleep, waiting for enough data or connection shutdown message from the sender. Idea to fix it is that rx kicks tx side to continue transmission (and may be close connection) when rx changes number of bytes to be woken up (e.g. SO_RCVLOWAT) and this value is bigger than number of available bytes to read. I've added small test for this, but not sure as it uses hardcoded value for maximum packet length, this value is defined in kernel header and used to control deferred credit update. And as this is not available to userspace, I can't control test parameters correctly (if one day this define will be changed - test may become useless). Head for this patchset is: https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=f1be1e04c76bb9c44789d3575bba4418cf0ea359 Link to v1: https://lore.kernel.org/netdev/20231108072004.1045669-1-avkrasnov@salutedevices.com/ Link to v2: https://lore.kernel.org/netdev/20231119204922.2251912-1-avkrasnov@salutedevices.com/ Link to v3: https://lore.kernel.org/netdev/20231122180510.2297075-1-avkrasnov@salutedevices.com/ Link to v4: https://lore.kernel.org/netdev/20231129212519.2938875-1-avkrasnov@salutedevices.com/ Link to v5: https://lore.kernel.org/netdev/20231130130840.253733-1-avkrasnov@salutedevices.com/ Changelog: v1 -> v2: * Patchset rebased and tested on new HEAD of net-next (see hash above). * New patch is added as 0001 - it removes return from SO_RCVLOWAT set callback in 'af_vsock.c' when transport callback is set - with that we can set 'sk_rcvlowat' only once in 'af_vsock.c' and in future do not copy-paste it to every transport. It was discussed in v1. * See per-patch changelog after ---. v2 -> v3: * See changelog after --- in 0003 only (0001 and 0002 still same). v3 -> v4: * Patchset rebased and tested on new HEAD of net-next (see hash above). * See per-patch changelog after ---. v4 -> v5: * Change patchset tag 'RFC' -> 'net-next'. * See per-patch changelog after ---. v5 -> v6: * New patch 0003 which sends credit update during reading bytes from socket. * See per-patch changelog after ---. Arseniy Krasnov (4): vsock: update SO_RCVLOWAT setting callback virtio/vsock: send credit update during setting SO_RCVLOWAT virtio/vsock: fix logic which reduces credit update messages vsock/test: two tests to check credit update logic drivers/vhost/vsock.c | 1 + include/linux/virtio_vsock.h | 1 + include/net/af_vsock.h | 2 +- net/vmw_vsock/af_vsock.c | 9 +- net/vmw_vsock/hyperv_transport.c | 4 +- net/vmw_vsock/virtio_transport.c | 1 + net/vmw_vsock/virtio_transport_common.c | 39 +++++- net/vmw_vsock/vsock_loopback.c | 1 + tools/testing/vsock/vsock_test.c | 175 ++++++++++++++++++++++++ 9 files changed, 226 insertions(+), 7 deletions(-)