[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH 0/2] x86/svm: Add support for Bus Lock Threshold
- To: Alejandro Vallejo <alejandro.garciavallejo@xxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxxx
- From: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
- Date: Tue, 20 Jan 2026 13:21:04 +0000
- Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=citrix.com; dmarc=pass action=none header.from=citrix.com; dkim=pass header.d=citrix.com; arc=none
- Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; 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=OOpw9wumMgg40LcpJzhhw6lrd8Hnq4Geo65K0tCzFkc=; b=Va61nO/WmTexJVzw5KNGNVNOedE3ed5Kfm/qU4I5b1Vu9xyaIl5ia8/awu7zvnEa45RLSTPJUBROcljcuHA5vSOi/ZJc8RjDBTh3osxIR+fXZvbjJCC1w7ZpmTzXbCOuFP6WX5yZBRSkvwaUyTgTupl1+JjBEAknqxAzK55eHXqfaWlHXxJ4HSgdCCNZeMGqp6zKIARj6vSwsFCbviCx7kIH1PgoFPbMFs+49G9AJ2wicQxjpyWg5uoMVG/ohqpgtRXD0wkt9rgapL+HRBpoDK2zdslyV9zZjnbKjNBtaDRBu1jWpWqDa/G5s+ys+CZU/dBfa0SYcO+mAOIDUEeNbw==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=VrOIIGCLu2oBRhuelGVdcj8ZMHoQQEgPHTnPsENNQNZcdlduCAz1PWxcq+lghlNWd4fhwXZC+BJeNBNg4ewYE97TuPAY2VMHHPg4B/bHyc+V3YX+2FfxXz0XiMmhI5j1ZCJY0kOAjmW6Vu79CrYRfWyU+8Kk9p2yd1Aki2WOGlcCBD6P25yZe939kV0CSB91T48fTbZTm1Tet7Iv+mXrMDQBcULJ4PvC87RFyoWkG5tCotaUqQpBbyJnuNGjE83Ttp972ZSI8nNu9uD0HiK07U2CyiwI+DB5bqnh1IOZGhL3O48wOvPByLwQbAtWe6UcGABMR8VS8XwFMfnqNYuxig==
- Authentication-results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=citrix.com;
- Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>, Jan Beulich <jbeulich@xxxxxxxx>, Roger Pau Monné <roger.pau@xxxxxxxxxx>, Jason Andryuk <jason.andryuk@xxxxxxx>, Stefano Stabellini <sstabellini@xxxxxxxxxx>
- Delivery-date: Tue, 20 Jan 2026 13:21:14 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
On 20/01/2026 11:22 am, Alejandro Vallejo wrote:
> On Tue Jan 20, 2026 at 10:53 AM CET, Alejandro Vallejo wrote:
>> Bus Locks are very costly and a VM left unchecked spamming instructions that
>> lock the memory bus (e.g: unaligned atomic CAS) makes system perf take a
>> nosedive. This patch is similar to BLD of VMX, but for SVM. It configures all
>> VMRUNs so they automatically exit at the first encounter of a buslock event,
>> effectively rate-limiting them.
> Does this warrant an entry in the CHANGELOG?
The Intel side got one (back in 4.18 and in the section about Sapphire
Rapids).
~Andrew
|
