From patchwork Thu Dec 5 14:01:22 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Durrant X-Patchwork-Id: 11274815 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3FFCA930 for ; Thu, 5 Dec 2019 14:02:58 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1A38F21823 for ; Thu, 5 Dec 2019 14:02:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="e/zfhcrU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1A38F21823 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=amazon.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1icrhd-0007C2-8i; Thu, 05 Dec 2019 14:01:57 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1icrhc-0007Bm-EY for xen-devel@lists.xenproject.org; Thu, 05 Dec 2019 14:01:56 +0000 X-Inumbo-ID: c87cec05-1767-11ea-8227-12813bfff9fa Received: from smtp-fw-9102.amazon.com (unknown [207.171.184.29]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id c87cec05-1767-11ea-8227-12813bfff9fa; Thu, 05 Dec 2019 14:01:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1575554511; x=1607090511; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=3V/slw6i8lEhvkIzZyT6X8o1Z4Oo4kiWfC2gC+XC92E=; b=e/zfhcrUs8YBDAcPMluZdoedp8ptazW6MdTWmvv2n3Gp2I5YgJvGgH2M OB/zj+lT2rtlUaewmWpgAYpSIZJnmQ+tu6XhvuLlyCvjbaVLY9DczknB4 nEiD7Aw0hg3TGgQKqVC5m1fHPhyoA9TCsGiKtgHHwbEUG5FChFofWLHA1 8=; IronPort-SDR: jZ7e9uzRrTtrcEfwO8IvA3gzi/yT0CgX020KZM87+W0LUhDIm/3rcRxMA2UpgNXRQmt4BPG2e6 WcmrHkejHKfA== X-IronPort-AV: E=Sophos;i="5.69,281,1571702400"; d="scan'208";a="11809799" Received: from sea32-co-svc-lb4-vlan3.sea.corp.amazon.com (HELO email-inbound-relay-1d-f273de60.us-east-1.amazon.com) ([10.47.23.38]) by smtp-border-fw-out-9102.sea19.amazon.com with ESMTP; 05 Dec 2019 14:01:42 +0000 Received: from EX13MTAUEA001.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan2.iad.amazon.com [10.40.159.162]) by email-inbound-relay-1d-f273de60.us-east-1.amazon.com (Postfix) with ESMTPS id F0512A283A; Thu, 5 Dec 2019 14:01:41 +0000 (UTC) Received: from EX13D32EUC001.ant.amazon.com (10.43.164.159) by EX13MTAUEA001.ant.amazon.com (10.43.61.243) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Thu, 5 Dec 2019 14:01:41 +0000 Received: from EX13MTAUWC001.ant.amazon.com (10.43.162.135) by EX13D32EUC001.ant.amazon.com (10.43.164.159) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Thu, 5 Dec 2019 14:01:39 +0000 Received: from u2f063a87eabd5f.cbg10.amazon.com (10.125.106.135) by mail-relay.amazon.com (10.43.162.232) with Microsoft SMTP Server id 15.0.1367.3 via Frontend Transport; Thu, 5 Dec 2019 14:01:38 +0000 From: Paul Durrant To: , Date: Thu, 5 Dec 2019 14:01:22 +0000 Message-ID: <20191205140123.3817-4-pdurrant@amazon.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191205140123.3817-1-pdurrant@amazon.com> References: <20191205140123.3817-1-pdurrant@amazon.com> MIME-Version: 1.0 Precedence: Bulk Subject: [Xen-devel] [PATCH 3/4] xen/interface: don't discard pending work in FRONT/BACK_RING_ATTACH X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Juergen Gross , Paul Durrant , Stefano Stabellini , Boris Ostrovsky Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Currently these macros will skip over any requests/responses that are added to the shared ring whilst it is detached. This, in general, is not a desirable semantic since most frontend implementations will eventually block waiting for a response which would either never appear or never be processed. NOTE: These macros are currently unused. BACK_RING_ATTACH(), however, will be used in a subsequent patch. Signed-off-by: Paul Durrant --- Cc: Boris Ostrovsky Cc: Juergen Gross Cc: Stefano Stabellini --- include/xen/interface/io/ring.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/xen/interface/io/ring.h b/include/xen/interface/io/ring.h index 3f40501fc60b..405adfed87e6 100644 --- a/include/xen/interface/io/ring.h +++ b/include/xen/interface/io/ring.h @@ -143,14 +143,14 @@ struct __name##_back_ring { \ #define FRONT_RING_ATTACH(_r, _s, __size) do { \ (_r)->sring = (_s); \ (_r)->req_prod_pvt = (_s)->req_prod; \ - (_r)->rsp_cons = (_s)->rsp_prod; \ + (_r)->rsp_cons = (_s)->req_prod; \ (_r)->nr_ents = __RING_SIZE(_s, __size); \ } while (0) #define BACK_RING_ATTACH(_r, _s, __size) do { \ (_r)->sring = (_s); \ (_r)->rsp_prod_pvt = (_s)->rsp_prod; \ - (_r)->req_cons = (_s)->req_prod; \ + (_r)->req_cons = (_s)->rsp_prod; \ (_r)->nr_ents = __RING_SIZE(_s, __size); \ } while (0)