linux-kernel - Re: [RFC PATCH v6 6/9] media: tegra: Add Tegra210 Video input driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <86bbcd55-fa13-5a35-e38b-c23745eafb87@gmail.com>
Date:   Mon, 6 Apr 2020 23:37:00 +0300
From:   Dmitry Osipenko <digetx@...il.com>
To:     Sowjanya Komatineni <skomatineni@...dia.com>,
        thierry.reding@...il.com, jonathanh@...dia.com, frankc@...dia.com,
        hverkuil@...all.nl, sakari.ailus@....fi, helen.koike@...labora.com
Cc:     sboyd@...nel.org, linux-media@...r.kernel.org,
        devicetree@...r.kernel.org, linux-clk@...r.kernel.org,
        linux-tegra@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [RFC PATCH v6 6/9] media: tegra: Add Tegra210 Video input driver

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?