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From: Oleksandr Grytsov <al1img@gmail.com>
Date: Wed, 23 Aug 2017 17:51:20 +0300
Message-ID: <CACvf2oUJtxVTuV0qu4z4kV=aSOH5O_8v=UjH_3tr4wCJdXuEjw@mail.gmail.com>
Subject: Re: [PATCH RESEND1 00/12] ALSA: vsnd: Add Xen para-virtualized
 frontend driver
To: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Cc: Oleksandr Andrushchenko <andr2000@gmail.com>, clemens@ladisch.de,
        alsa-devel@alsa-project.org, xen-devel@lists.xen.org,
        linux-kernel@vger.kernel.org, tiwai@suse.com,
        Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
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Hi,

Thank you for detailed explanation.

We understand that emulated interrupt on the frontend side is completely not
acceptable and definitely we need to provide some feedback mechanism from
Dom0 to DomU.

In our case it is technically impossible to provide precise period interrupt
(mostly because our backend is a user space application).
The best we can implement it is provide number of frames (time, bytes etc.)
consumed by real HW. This info will be outdated due to different delays but
we can provide precise timestamps when this info was acquired.

Would this info be useful to update the frontend driver state?

If you have in mind any other solution we would appreciate.

-- 
Best Regards,
Oleksandr Grytsov.