From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Osipenko Subject: Re: [RFC PATCH v11 6/9] media: tegra: Add Tegra210 Video input driver Date: Thu, 30 Apr 2020 17:02:19 +0300 Message-ID: <4da289e6-036f-853b-beb4-379d6462adb0@gmail.com> References: <1588197606-32124-1-git-send-email-skomatineni@nvidia.com> <1588197606-32124-7-git-send-email-skomatineni@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Content-Language: en-US Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sowjanya Komatineni , thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, jonathanh-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org, frankc-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org, hverkuil-qWit8jRvyhVmR6Xm/wNWPw@public.gmane.org, sakari.ailus-X3B1VOXEql0@public.gmane.org, helen.koike-ZGY8ohtN/8qB+jHODAdFcQ@public.gmane.org Cc: sboyd-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-media-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-clk-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-tegra@vger.kernel.org 30.04.2020 16:56, Dmitry Osipenko пишет: > 30.04.2020 01:00, Sowjanya Komatineni пишет: >> +static int chan_capture_kthread_finish(void *data) >> +{ >> + struct tegra_vi_channel *chan = data; >> + struct tegra_channel_buffer *buf; >> + >> + set_freezable(); >> + >> + while (1) { >> + try_to_freeze(); > > I guess it won't be great to freeze in the middle of a capture process, so: > if (list_empty(&chan->done)) > try_to_freeze(); And here should be some locking protection in order not race with the chan_capture_kthread_start because kthread_finish could freeze before kthread_start. >> + wait_event_interruptible(chan->done_wait, >> + !list_empty(&chan->done) || >> + kthread_should_stop()); >> + >> + /* dequeue buffers and finish capture */ >> + buf = dequeue_buf_done(chan); >> + while (buf) { >> + tegra_channel_capture_done(chan, buf); >> + buf = dequeue_buf_done(chan); >> + } >> + >> + if (kthread_should_stop()) >> + break; >> + } >> + >> + return 0; >> +} > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D76A6C4724C for ; 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[91.78.208.152]) by smtp.googlemail.com with ESMTPSA id v8sm4886684lfp.85.2020.04.30.07.02.20 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 30 Apr 2020 07:02:20 -0700 (PDT) Subject: Re: [RFC PATCH v11 6/9] media: tegra: Add Tegra210 Video input driver From: Dmitry Osipenko To: Sowjanya Komatineni , thierry.reding@gmail.com, jonathanh@nvidia.com, frankc@nvidia.com, hverkuil@xs4all.nl, sakari.ailus@iki.fi, helen.koike@collabora.com Cc: sboyd@kernel.org, linux-media@vger.kernel.org, devicetree@vger.kernel.org, linux-clk@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org References: <1588197606-32124-1-git-send-email-skomatineni@nvidia.com> <1588197606-32124-7-git-send-email-skomatineni@nvidia.com> Message-ID: <4da289e6-036f-853b-beb4-379d6462adb0@gmail.com> Date: Thu, 30 Apr 2020 17:02:19 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 30.04.2020 16:56, Dmitry Osipenko пишет: > 30.04.2020 01:00, Sowjanya Komatineni пишет: >> +static int chan_capture_kthread_finish(void *data) >> +{ >> + struct tegra_vi_channel *chan = data; >> + struct tegra_channel_buffer *buf; >> + >> + set_freezable(); >> + >> + while (1) { >> + try_to_freeze(); > > I guess it won't be great to freeze in the middle of a capture process, so: > if (list_empty(&chan->done)) > try_to_freeze(); And here should be some locking protection in order not race with the chan_capture_kthread_start because kthread_finish could freeze before kthread_start. >> + wait_event_interruptible(chan->done_wait, >> + !list_empty(&chan->done) || >> + kthread_should_stop()); >> + >> + /* dequeue buffers and finish capture */ >> + buf = dequeue_buf_done(chan); >> + while (buf) { >> + tegra_channel_capture_done(chan, buf); >> + buf = dequeue_buf_done(chan); >> + } >> + >> + if (kthread_should_stop()) >> + break; >> + } >> + >> + return 0; >> +} >