[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v2 2/6] gnttab: allow setting max version per-domain
- To: Roger Pau Monne <roger.pau@xxxxxxxxxx>
- From: Jan Beulich <jbeulich@xxxxxxxx>
- Date: Fri, 15 Oct 2021 11:48:33 +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=hxyHKNc/iXTt0TtTxZAJo9ZsPSW3psvBcn7Q+Jb4ATA=; b=JRLe43yvYr0T1DTQGiDp273CswCv767jN2w80KmPgi0zSsMyKEwbwCn2cllXrZVWzJXsKm1vRqQ7TWp7lH7AlabE52KHyaW4LmADiIWY4E96GZh27oZ4fXrK8V1UF8ZPjaY8enkd4SJF4j2uIAgvOsZ4YxoCPDrR3yBPpW55b1c3jmm0gZvpVU0GuHWUDrONiH5+EaiF57DcHvIerXUeMHohTRKjC5ZD4V+G514jvEVELAGnp0iQ0UqsYGl+yqY5wiqIrQPDTnP+E0W0oU5ha8XISu7P8SUX+yiDflskRtzgFzArOIAW+UUPrvjJSr6AmHKeHd+BCX5LfKR84Wqbeg==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=ZtoIcMEppkhWYmP6Nc2S5/INRZUWcdBXj0pM34Rf9FFsFY9uRNLCnSSQTBUjF3WszVoJNKVPR9bGsI+cQC7AgFW4JJWuRNqkXFJCQMHRZx2ALV0WYpxunesSX9BEGQ9aiy661XknJbFC2ztwvgL+tBN20GqSOsVrJa9iC+JK7NQ4NsG/tb4G8P+6Iu7RqBIqGJW5FYdbVWqnpHTwl/jxHn1hourZIy1s2D969i1Uo3rkfHadV3v5xnqT39i7McK7OK21dty4aGix+Qwm5lYBrmehuLK529Ge6xhrc50mM9iPu31wKV2O8jdhBkA+FX+OI74brcZ+z6CNb6mDslzroA==
- Authentication-results: lists.xenproject.org; dkim=none (message not signed) header.d=none;lists.xenproject.org; dmarc=none action=none header.from=suse.com;
- Cc: Ian Jackson <iwj@xxxxxxxxxxxxxx>, Wei Liu <wl@xxxxxxx>, Andrew Cooper <andrew.cooper3@xxxxxxxxxx>, George Dunlap <george.dunlap@xxxxxxxxxx>, Julien Grall <julien@xxxxxxx>, Stefano Stabellini <sstabellini@xxxxxxxxxx>, Anthony PERARD <anthony.perard@xxxxxxxxxx>, Juergen Gross <jgross@xxxxxxxx>, Christian Lindig <christian.lindig@xxxxxxxxxx>, David Scott <dave@xxxxxxxxxx>, Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxxx
- Delivery-date: Fri, 15 Oct 2021 09:48:47 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
On 15.10.2021 11:39, Jan Beulich wrote:
> On 22.09.2021 10:21, Roger Pau Monne wrote:
>> --- a/xen/include/public/domctl.h
>> +++ b/xen/include/public/domctl.h
>> @@ -87,14 +87,22 @@ struct xen_domctl_createdomain {
>> /*
>> * Various domain limits, which impact the quantity of resources
>> * (global mapping space, xenheap, etc) a guest may consume. For
>> - * max_grant_frames and max_maptrack_frames, < 0 means "use the
>> - * default maximum value in the hypervisor".
>> + * max_grant_frames, max_maptrack_frames and max_gnttab_version < 0
>> + * means "use the default maximum value in the hypervisor".
>> */
>> uint32_t max_vcpus;
>> uint32_t max_evtchn_port;
>> int32_t max_grant_frames;
>> int32_t max_maptrack_frames;
>>
>> +/* Grant version, use low 4 bits. */
>> +#define XEN_DOMCTL_GRANT_version_mask 0xf
>> +#define XEN_DOMCTL_GRANT_version_default 0xf
>> +
>> +#define XEN_DOMCTLGRANT_MAX XEN_DOMCTL_GRANT_version_mask
>> +
>> + uint32_t grant_opts;
>
> As it now seems unlikely that this will make 4.16, please don't forget
> to bump the interface version for 4.17. With that and preferably with
> the nit above addressed, hypervisor parts:
> Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
Actually no, I'm afraid there is an issue with migration: If the tool
stack remembers the "use default" setting and hands this to the new
host, that host's default may be different from the source host's. It
is the effective max-version that needs passing on in this case, which
in turn requires a means to obtain the value.
Jan
|
