[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v3 03/11] x86/vlapic: introduce an EOI callback mechanism
- To: Jan Beulich <jbeulich@xxxxxxxx>
- From: Roger Pau Monné <roger.pau@xxxxxxxxxx>
- Date: Thu, 8 Apr 2021 12:56:25 +0200
- 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=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=4plYT3kwfqlsfaN5Z7x8AP7vWs9lfN2zMHdNyb3d314=; b=TzpPYLn+3SeHt35mkCLOuFAAYnp9eBszkxbS6cbcqfsx/Y6RVEr+/9LjbEIHWTBMOsNwh/ROzpD7o/O3B7MbOimOtUI9L7xbayBoiJFhhPFacPqwgdp91ceUTN21enx90IRLYZ9j+COamR9LsXrvM+ptL7hKTURiAAz+8zw1Qqh01EBZv81WSB49Rf/5ii2OqGJbHyDhMG17SH3OTiYqewLZdGV+CpouyxhyKzptvXala3jeseYqRGKBqUOZkZUfPMTvmrDDQ3HQVihBSDsfLjyTdFYEHEiNAMl2dcOTkjM6HHqhR0+eBgWLEHvi1XDQQpGq/FqZovpKe08iPyRBWQ==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=itKeXGxj7cmzLSVZ5li35DVyAA0VGKMXt+z1Z2wkJVszXt094rHVP0xnT2V0zI5DUc2oSVEPxKe0hDQQaQ4PJYjvhHGdpNr2tHQCGNBzxsv/8RTcNKP947wTteMnyIkRErNRcQcaNcAgOoJXit3eWBLMiS9HPTX9xsHojqGVH/nwnJKu36yTMNJLS1qXf5JLhfyUVmVziuuWwkRMRrlOWEfCuh6T08RFFPhhCe00DnqhjAxOfDxKY6PCAw0o9QSSlJcfwUVlh9RvIJloCLLUlV73gw5C5SDkAnqM3IwoSs0DXYKQrHd+BIdBWfiU8uHCh82MRr13KVP42a07TKZoJA==
- Authentication-results: esa3.hc3370-68.iphmx.com; dkim=pass (signature verified) header.i=@citrix.onmicrosoft.com
- Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>, Wei Liu <wl@xxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxxx>
- Delivery-date: Thu, 08 Apr 2021 10:56:39 +0000
- Ironport-hdrordr: A9a23:I3WvCqGsP6Z/w0hipLqFOpHXdLJzesId70hD6mlYVQFVfsuEl8 qngfQc0lvOhCwMXWw78OrsBICrSxrnlaJdy48XILukQU3aqHKlRbsSibfK7h/BP2nF9uBb3b p9aKQWMrfNJHVzkMqS2maFOvk6xt3vys6VrMP/61socg1wcaFn6G5Ce2OmO2l7XhNPC5Z8NL f03LslmxOadX4abtu2CxA+NoCum/TxmI/7ehlDPhY76WC15g+A0qLwEBSTw34lIlFy6IolmF KlryXJop+Nntv+4R/a2m/V4f1t6abc4+oGPuOgoIw4Lj3tjyyheYhuXaaT1QpF3N2H2RIRv/ Tn5zsmIsRv+1PdF1vF3ifF6k3b/xsFr1/k1FOCjnPoraXCNUwHIvsEv611WF/9ySMbzbZB+Z MO5U21nd5rKCmFuyLH693BR3hR5zGJiEtnq8E/pThiS4cEAYUhy7A3zQduP7orOjn104wjGP kGNrCn2N9mNWmXaH3UpQBUsaWRd0V2Gh+HR34LsdCO3w5Xm2hkz1AZyNZ3pAZ5yK4A
- Ironport-sdr: f/BYWX0BW8RZdqw1vOdUiXB05Bxsit6SFSV+MA+Tu+1ty6PQnJ1hz1cBanBAXRbxFVDAFEIONJ 3wFhwftaaSc60vrg/eF21/U8bYzIHXM5r9Qofdjq/yEVJh4LbI3Zou1o3L/9icsG2Kw43vHENa eOA3X15V4uUn5PlP13koiSkiWefRjxzx+A4SE5ms8ZcUtKEdJ5x6q0dkhxypJymhMkERoYf2Zy /8PPi3w9ZN1jf+ucNx65e2yBrb62jZe4E16Lp+RKwOdqmE/4NmDxJkYApz80kq6D8uoCTbfTeb wZU=
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
On Thu, Apr 08, 2021 at 12:49:44PM +0200, Jan Beulich wrote:
> On 08.04.2021 11:12, Roger Pau Monné wrote:
> > On Thu, Apr 08, 2021 at 08:20:15AM +0200, Jan Beulich wrote:
> >> On 07.04.2021 18:27, Roger Pau Monné wrote:
> >>> On Wed, Apr 07, 2021 at 04:55:43PM +0200, Jan Beulich wrote:
> >>>> On 31.03.2021 12:32, Roger Pau Monne wrote:
> >>>>> Add a new vlapic_set_irq_callback helper in order to inject a vector
> >>>>> and set a callback to be executed when the guest performs the end of
> >>>>> interrupt acknowledgment.
> >>>>>
> >>>>> Such functionality will be used to migrate the current ad hoc handling
> >>>>> done in vlapic_handle_EOI for the vectors that require some logic to
> >>>>> be executed when the end of interrupt is performed.
> >>>>>
> >>>>> The setter of the callback will be in charge for setting the callback
> >>>>> again on resume. That is the reason why vlapic_set_callback is not a
> >>>>> static function.
> >>>>
> >>>> I'm struggling with your use of "resume" here: Resuming from S3
> >>>> doesn't require re-doing anything that's kept in memory, does it?
> >>>> So what meaning does the word have here?
> >>>
> >>> Right, I can see the confusion. Resume here means a guest being
> >>> migrated or restored, not Xen itself being resumed. Callbacks are not
> >>> part of the exported guest state, and hence any emulated device that
> >>> requires a callback will have to register it as part of loading the
> >>> saved state.
> >>>
> >>>> Apart from this, and with the xzalloc_array() change requested
> >>>> by Andrew, this looks good to me.
> >>
> >> In which case with this change and "resume" replaced suitably in the
> >> description
> >
> > I've worded it as:
> >
> > "The setter of the callback will be in charge for setting the callback
> > again on guest restore or resume, as callbacks are not saved as part
> > of the vlapic state. That is the reason why vlapic_set_callback is not
> > a static function."
>
> Hmm, you still mention "resume", which makes me continue to wonder
> what you're thinking of beyond guest restore.
Urg, yes, let me remove that resume.
Thanks, Roger.
|
