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Subject: Re: [RFC PATCH v6 6/9] media: tegra: Add Tegra210 Video input driver
To:     Sowjanya Komatineni <skomatineni@nvidia.com>,
        thierry.reding@gmail.com, jonathanh@nvidia.com, frankc@nvidia.com,
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From:   Dmitry Osipenko <digetx@gmail.com>
Message-ID: <86bbcd55-fa13-5a35-e38b-c23745eafb87@gmail.com>
Date:   Mon, 6 Apr 2020 23:37:00 +0300
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06.04.2020 23:20, Sowjanya Komatineni пишет:
> 
> On 4/6/20 1:02 PM, Dmitry Osipenko wrote:
>> External email: Use caution opening links or attachments
>>
>>
>> 04.04.2020 04:25, Sowjanya Komatineni пишет:
>> ...
>>> +static int chan_capture_kthread_start(void *data)
>>> +{
>>> +     struct tegra_vi_channel *chan = data;
>>> +     struct tegra_channel_buffer *buf;
>>> +     int err = 0;
>>> +     int caps_inflight;
>>> +
>>> +     set_freezable();
>>> +
>>> +     while (1) {
>>> +             try_to_freeze();
>>> +
>>> +             wait_event_interruptible(chan->start_wait,
>>> +                                      !list_empty(&chan->capture) ||
>>> +                                      kthread_should_stop());
>> Is it really okay that list_empty() isn't protected with a lock?
>>
>> Why wait_event is "interruptible"?
> 
> To allow it to sleep until wakeup on thread it to avoid constant
> checking for condition even when no buffers are ready, basically to
> prevent blocking.

So the "interrupt" is for getting event about kthread_should_stop(),
correct?