[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH] x86: limit issuing of IBPB during context switch
- To: Andrew Cooper <Andrew.Cooper3@xxxxxxxxxx>
- From: Jan Beulich <jbeulich@xxxxxxxx>
- Date: Mon, 25 Jul 2022 14:27:36 +0200
- Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=suse.com; dmarc=pass action=none header.from=suse.com; dkim=pass header.d=suse.com; arc=none
- Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=RbUmj3ceKPymepo19iMVy/3v7AEDccGvYecKu3QwyVM=; b=oDjMnDaf1Y8FM72t6eUM44n1gdQqeXxz7HIHCE3JrJgVUorEfXDhuoWY4nPwIlMD0cWHY9uWJfbZPUxrUzIxVq8RxJH7cOnemAdofZmPf2/tvcbVJrFwOXRn6GpfIvavBMMNSvBWgg07c8SN9E5ZSTyQrDZ8nW6KVUMZSJILlmJfOkNEtZWx0W5R/H2JdXtEMX+ocp0kgYCo6qPVbVXpClWoz9H6+lrAdKB04xKKsw5DicCglgV0DpiO/Jix8sxSA6vZuokfyzFTlJ7juU5VXSA5/+MoioyZn5iIrASFQYwu04aOVmCnaJMrK02GRQ1St4xK+rgMJN16ktPCx167WQ==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=NJ9PwsNLb9gvhZHujDMvCsjIPZhHW6Yg+EexJlS4GOBvJgpzo/PkADswNlYKnzN+viB5EPXFmPoqVj67HXhe5HEzBsavbIH5wIOlwJDq2nbVetmpcaErvpft+BNWXgli/2VPM3K1Hm14kqkUsCi7t8c8+aP2CgOTp+BDMVm2Su61czat3CJqbQZV4Nuhgsj8vzXsdxrbeJVdOc4EmDD2iqJxmKUN+EWmwdJ81MOsBT/G1YLyOGNfnpHPTsVqxeqBQEk2ajRql+ulFqjM1ujGbtUWE4KuhB+mvLNP0fMTf3UnquPMLbJdIaRm3HCcEKnlVu6w0DKNTxiSnUuPMzdjtg==
- Authentication-results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=suse.com;
- Cc: Wei Liu <wl@xxxxxxx>, Roger Pau Monne <roger.pau@xxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>
- Delivery-date: Mon, 25 Jul 2022 12:27:43 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
On 25.07.2022 14:15, Andrew Cooper wrote:
> On 25/07/2022 13:09, Jan Beulich wrote:
>> When the outgoing vCPU had IBPB issued upon entering Xen there's no
>> need for a 2nd barrier during context switch.
>>
>> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
>
> That's already accounted for by opt_ibpb_ctxt_switch conditionally being
> not set.
That option defaults to false only if both PV and HVM have the entry
barrier turned on. In fact, if it wasn't for Dom0 I was first thinking
the global could go away and only the per-domain setting could be
inspected here.
Jan
|
