From nobody Mon May 6 12:41:04 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org ARC-Seal: i=1; a=rsa-sha256; t=1566555410; cv=none; d=zoho.com; s=zohoarc; b=n7QDEWaxjgonvSr+HdsOfCMQxjaBF67qOQX+eyWWsFjHEItiHo6vPuIjbiB1e3iw8e3l2jLstLfIAZnDxOU1e+npxRNzdv2pkKFxedjBeRHaKD7Vj97vC7AFWfjwU4GdOU7HFYtCg9IOr4Zr6QdwVygyuOlrI+yH+rK9BTTQxzo= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1566555410; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To:ARC-Authentication-Results; bh=dSs87nYLFNnPh4SotLS5BkKO9kKGwqZQVsZRjFHjgBk=; b=O0ftKIo8ckRoon9aTmWxPCXIemfZvWTZb7btVHgOjUFQ3VCFWEiEcltL+vfO3/snyZnt10+i4sqX9w3BwPEjOENqrp2W24tnTerXy8QJOXYUxV3+s2mfwPosQD9Ski4xvioMcC2g61HoNeEQGucu7xGwd3FlpCGJN7rU8zSQSgU= ARC-Authentication-Results: i=1; mx.zoho.com; dkim=fail; spf=none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1566555410826474.8681949398833; Fri, 23 Aug 2019 03:16:50 -0700 (PDT) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1i16bh-0004LN-25; Fri, 23 Aug 2019 10:15:45 +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 1i16bg-0004LC-5D for xen-devel@lists.xenproject.org; Fri, 23 Aug 2019 10:15:44 +0000 Received: from esa3.hc3370-68.iphmx.com (unknown [216.71.145.155]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id f5d7b4c2-c58e-11e9-ade4-12813bfff9fa; Fri, 23 Aug 2019 10:15:43 +0000 (UTC) X-Inumbo-ID: f5d7b4c2-c58e-11e9-ade4-12813bfff9fa DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=citrix.com; s=securemail; t=1566555343; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=X1XvM8CMt3Oe1WMwqnuj+nuos2M8xn2yAGimqZ6nzIE=; b=gRGNoskI4kUyNpDFS1k46JSHrXmv2qB8b1MYFsAmRWBmA9kI8QdvB6s1 f2f1L4RmwJzPBd/ENxceYfG4jefYZECFEx/B0A+ZroWIJotqIp4H47yDc v4DqkNjZBbtHkPm/nFxjlQuyGFzQsN9P31D0+B/sXBIdVaIhFBzAjZixY o=; Authentication-Results: esa3.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none; spf=None smtp.pra=anthony.perard@citrix.com; spf=Pass smtp.mailfrom=anthony.perard@citrix.com; spf=None smtp.helo=postmaster@mail.citrix.com Received-SPF: none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Received-SPF: None (esa3.hc3370-68.iphmx.com: no sender authenticity information available from domain of anthony.perard@citrix.com) identity=pra; client-ip=162.221.158.21; receiver=esa3.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="anthony.perard@citrix.com"; x-conformance=sidf_compatible Received-SPF: Pass (esa3.hc3370-68.iphmx.com: domain of anthony.perard@citrix.com designates 162.221.158.21 as permitted sender) identity=mailfrom; client-ip=162.221.158.21; receiver=esa3.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="anthony.perard@citrix.com"; x-conformance=sidf_compatible; x-record-type="v=spf1"; x-record-text="v=spf1 ip4:209.167.231.154 ip4:178.63.86.133 ip4:195.66.111.40/30 ip4:85.115.9.32/28 ip4:199.102.83.4 ip4:192.28.146.160 ip4:192.28.146.107 ip4:216.52.6.88 ip4:216.52.6.188 ip4:162.221.158.21 ip4:162.221.156.83 ~all" Received-SPF: None (esa3.hc3370-68.iphmx.com: no sender authenticity information available from domain of postmaster@mail.citrix.com) identity=helo; client-ip=162.221.158.21; receiver=esa3.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="postmaster@mail.citrix.com"; x-conformance=sidf_compatible IronPort-SDR: NWMLEnhoWu1IGDRVUxUzlhnxVQXUUvE0LXTYSHLVN2dfjQGP8cAZrA8Z/TMkiFe9+qvAxxwuDh GVBZJchi8a1f/hL98sIzSu853Sn8XzdzuO+Q+dHVIlYqFXrXM8uqSncWNxJ1I4NmjUnmoV/u9c uY52GiGvycKH6fQkM/Lc6Xyp9sWRhAdt+h9fXfZLvjhEPzRLSyOROMkqNyi4eOxSyB9FYTRerc mWY5ZsTjqOJmSqfgV0bF50b2xglWligVaJIvxN6BQku8+Kl3b5MkCapEV27paO5z3ASXl6q28f VKk= X-SBRS: 2.7 X-MesageID: 4640483 X-Ironport-Server: esa3.hc3370-68.iphmx.com X-Remote-IP: 162.221.158.21 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.64,420,1559534400"; d="scan'208";a="4640483" From: Anthony PERARD To: Date: Fri, 23 Aug 2019 11:15:33 +0100 Message-ID: <20190823101534.465-2-anthony.perard@citrix.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190823101534.465-1-anthony.perard@citrix.com> References: <20190823101534.465-1-anthony.perard@citrix.com> MIME-Version: 1.0 Subject: [Xen-devel] [PATCH v2 1/2] xen-bus: Fix backend state transition on device reset X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Anthony PERARD , xen-devel@lists.xenproject.org, Stefano Stabellini , qemu-stable@nongnu.org, Paul Durrant Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) When a frontend wants to reset its state and the backend one, it starts with setting "Closing", then waits for the backend (QEMU) to do the same. But when QEMU is setting "Closing" to its state, it triggers an event (xenstore watch) that re-execute xen_device_backend_changed() and set the backend state to "Closed". QEMU should wait for the frontend to set "Closed" before doing the same. Before setting "Closed" to the backend_state, we are also going to check if there is a frontend. If that the case, when the backend state is set to "Closing" the frontend should react and sets its state to "Closing" then "Closed". The backend should wait for that to happen. Fixes: b6af8926fb858c4f1426e5acb2cfc1f0580ec98a Signed-off-by: Anthony PERARD Reviewed-by: Paul Durrant --- Cc: qemu-stable@nongnu.org --- Notes: v2: - use a helper - Add InitWait and Initialised to the list of active state hw/xen/xen-bus.c | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) diff --git a/hw/xen/xen-bus.c b/hw/xen/xen-bus.c index e40500242d..62c127b926 100644 --- a/hw/xen/xen-bus.c +++ b/hw/xen/xen-bus.c @@ -516,6 +516,23 @@ static void xen_device_backend_set_online(XenDevice *x= endev, bool online) xen_device_backend_printf(xendev, "online", "%u", online); } =20 +/* + * Tell from the state whether the frontend is likely alive, + * i.e. it will react to a change of state of the backend. + */ +static bool xen_device_state_is_active(enum xenbus_state state) +{ + switch (state) { + case XenbusStateInitWait: + case XenbusStateInitialised: + case XenbusStateConnected: + case XenbusStateClosing: + return true; + default: + return false; + } +} + static void xen_device_backend_changed(void *opaque) { XenDevice *xendev =3D opaque; @@ -539,11 +556,11 @@ static void xen_device_backend_changed(void *opaque) =20 /* * If the toolstack (or unplug request callback) has set the backend - * state to Closing, but there is no active frontend (i.e. the - * state is not Connected) then set the backend state to Closed. + * state to Closing, but there is no active frontend then set the + * backend state to Closed. */ if (xendev->backend_state =3D=3D XenbusStateClosing && - xendev->frontend_state !=3D XenbusStateConnected) { + !xen_device_state_is_active(state)) { xen_device_backend_set_state(xendev, XenbusStateClosed); } =20 --=20 Anthony PERARD _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel From nobody Mon May 6 12:41:04 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org ARC-Seal: i=1; a=rsa-sha256; t=1566555411; cv=none; d=zoho.com; s=zohoarc; b=DBdMtAZfU3hexEO/uc8SEp34adOR5fxcWN+3Dpmqlt9vpn4IvR+E32CYed5AfgO6eiLVwsTaii8yzy1s8vJWD5Zm31vDx9UcT+QlM1ch5eT+xUaxUI5It429yVIyoEU4R3t9Sn+rNzJ7MkG58uvQiKD7Zm/MgW1VPf+OdUTg4ik= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1566555411; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To:ARC-Authentication-Results; bh=TMH+wsodQqUTeAq0RAEWEWHOF/COaOpusG+apRz6Z5I=; b=QJDqXVzeDHtN7M8l84H1PxId9Mcpt/VO+4CNaSI9pTzdYCMbRjNz89Vj8HIHPU1repKcxU1GTz0s72axynuJtbryfPxr8oxVss5aRPmsEIOUtLMyPc/tK/ZX3vjlmemHoR7/uIWbKGGO/PthH2z5J0m4owN6OqShfbDY01bhecQ= ARC-Authentication-Results: i=1; mx.zoho.com; dkim=fail; spf=none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1566555410864967.9709319618205; Fri, 23 Aug 2019 03:16:50 -0700 (PDT) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1i16bi-0004LU-BT; Fri, 23 Aug 2019 10:15:46 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1i16bg-0004LH-Fb for xen-devel@lists.xenproject.org; Fri, 23 Aug 2019 10:15:44 +0000 Received: from esa5.hc3370-68.iphmx.com (unknown [216.71.155.168]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id f6c72802-c58e-11e9-b95f-bc764e2007e4; Fri, 23 Aug 2019 10:15:43 +0000 (UTC) X-Inumbo-ID: f6c72802-c58e-11e9-b95f-bc764e2007e4 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=citrix.com; s=securemail; t=1566555343; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=DO7MoqGCq5qbArgpzvN9mrrcRAyCtPBqzcT7RIE96GA=; b=JLQchPz5y1Ran5JwpZqbC0ij+J7QMXEGx0X5nxfUY+gcuCSQmn9rfFAp DJBsLXB9f1KWM3x4jn7hCQXS0WK2gKZ71DTVDdhlO237HQz9YLsIvwzMi BHFjZx4frfdtMkal6T6q7aeid2PWvvIrDPkqJ9evXCfX1tcShNRTKxO5B Y=; Authentication-Results: esa5.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none; spf=None smtp.pra=anthony.perard@citrix.com; spf=Pass smtp.mailfrom=anthony.perard@citrix.com; spf=None smtp.helo=postmaster@mail.citrix.com Received-SPF: none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Received-SPF: None (esa5.hc3370-68.iphmx.com: no sender authenticity information available from domain of anthony.perard@citrix.com) identity=pra; client-ip=162.221.158.21; receiver=esa5.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="anthony.perard@citrix.com"; x-conformance=sidf_compatible Received-SPF: Pass (esa5.hc3370-68.iphmx.com: domain of anthony.perard@citrix.com designates 162.221.158.21 as permitted sender) identity=mailfrom; client-ip=162.221.158.21; receiver=esa5.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="anthony.perard@citrix.com"; x-conformance=sidf_compatible; x-record-type="v=spf1"; x-record-text="v=spf1 ip4:209.167.231.154 ip4:178.63.86.133 ip4:195.66.111.40/30 ip4:85.115.9.32/28 ip4:199.102.83.4 ip4:192.28.146.160 ip4:192.28.146.107 ip4:216.52.6.88 ip4:216.52.6.188 ip4:162.221.158.21 ip4:162.221.156.83 ~all" Received-SPF: None (esa5.hc3370-68.iphmx.com: no sender authenticity information available from domain of postmaster@mail.citrix.com) identity=helo; client-ip=162.221.158.21; receiver=esa5.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="postmaster@mail.citrix.com"; x-conformance=sidf_compatible IronPort-SDR: v8P0wpMEi2lEQzdfPnrao0+KylUCNC2SltQiJLyCRaJB/kQ7xkxNq5rE7G/31lWGW305AnybbM Z5UA8PzCKcInMvhzQvCq6I693L/5BRmr6uUQkfU7J12Io7VrjpuX+pBu4HecD/kQmruj8CoO5n N8xmScIB/SPvU2oBRybd5L2ehHrMrj23Sw4RCq7l0ipbTryt4NPBu+sjDR63KZRpcv5RavYdc2 UYVcwMtjayz7xla6MXFDDVkJzCAbnS8d/NmvVXmLPa3TaTmz72/FkSth1JtgDUY/OEJ1ecxlyu cOI= X-SBRS: 2.7 X-MesageID: 4814135 X-Ironport-Server: esa5.hc3370-68.iphmx.com X-Remote-IP: 162.221.158.21 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.64,420,1559534400"; d="scan'208";a="4814135" From: Anthony PERARD To: Date: Fri, 23 Aug 2019 11:15:34 +0100 Message-ID: <20190823101534.465-3-anthony.perard@citrix.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190823101534.465-1-anthony.perard@citrix.com> References: <20190823101534.465-1-anthony.perard@citrix.com> MIME-Version: 1.0 Subject: [Xen-devel] [PATCH v2 2/2] xen-bus: Avoid rewriting identical values to xenstore X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Anthony PERARD , xen-devel@lists.xenproject.org, Stefano Stabellini , Paul Durrant Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) When QEMU receives a xenstore watch event suggesting that the "state" of the frontend changed, it records this in its own state but it also re-write the value back into xenstore even so there were no change. This triggers an unnecessary xenstore watch event which QEMU will process again (and maybe the frontend as well). Also QEMU could potentially write an already old value. Signed-off-by: Anthony PERARD Reviewed-by: Paul Durrant --- Notes: v2: - fix coding style - only change frontend_set_state() and use 'publish' instead of 'export= '. hw/xen/xen-bus.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/hw/xen/xen-bus.c b/hw/xen/xen-bus.c index 62c127b926..a04478ad4f 100644 --- a/hw/xen/xen-bus.c +++ b/hw/xen/xen-bus.c @@ -698,7 +698,8 @@ int xen_device_frontend_scanf(XenDevice *xendev, const = char *key, } =20 static void xen_device_frontend_set_state(XenDevice *xendev, - enum xenbus_state state) + enum xenbus_state state, + bool publish) { const char *type =3D object_get_typename(OBJECT(xendev)); =20 @@ -710,7 +711,9 @@ static void xen_device_frontend_set_state(XenDevice *xe= ndev, xs_strstate(state)); =20 xendev->frontend_state =3D state; - xen_device_frontend_printf(xendev, "state", "%u", state); + if (publish) { + xen_device_frontend_printf(xendev, "state", "%u", state); + } } =20 static void xen_device_frontend_changed(void *opaque) @@ -726,7 +729,7 @@ static void xen_device_frontend_changed(void *opaque) state =3D XenbusStateUnknown; } =20 - xen_device_frontend_set_state(xendev, state); + xen_device_frontend_set_state(xendev, state, false); =20 if (state =3D=3D XenbusStateInitialising && xendev->backend_state =3D=3D XenbusStateClosed && @@ -1169,7 +1172,7 @@ static void xen_device_realize(DeviceState *dev, Erro= r **errp) xen_device_frontend_printf(xendev, "backend-id", "%u", xenbus->backend_id); =20 - xen_device_frontend_set_state(xendev, XenbusStateInitialising); + xen_device_frontend_set_state(xendev, XenbusStateInitialising, true); =20 xendev->exit.notify =3D xen_device_exit; qemu_add_exit_notifier(&xendev->exit); --=20 Anthony PERARD _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel