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Date:   Mon, 20 Sep 2021 11:18:35 +0530
From:   dikshita@codeaurora.org
To:     Stephen Boyd <swboyd@chromium.org>
Cc:     Stanimir Varbanov <stanimir.varbanov@linaro.org>,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-media@vger.kernel.org, jim.cromie@gmail.com,
        Joe Perches <joe@perches.com>, Jason Baron <jbaron@akamai.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-media-owner@vger.kernel.org,
        Akinobu Mita <akinobu.mita@gmail.com>
Subject: Re: [PATCH v5 2/3] venus: Add a debugfs file for SSR trigger
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On 2021-09-17 11:48, Stephen Boyd wrote:
> Quoting dikshita@codeaurora.org (2021-09-15 23:29:36)
>> On 2021-09-16 01:09, Stephen Boyd wrote:
>> > Quoting dikshita@codeaurora.org (2021-09-15 02:13:09)
>> >>
>> >> So, IMO, we will have to use custom debugfs only.
>> >
>> > Can you use DECLARE_FAULT_ATTR()? Or you need it to be active instead
>> > of
>> > passive, i.e. it shouldn't wait for should_fail() to return true, but
>> > actively trigger something on the remoteproc?
>> >
>> 
>> yes, it doesn't need to wait for should_fail() to return true.
>> the client/user should be able to trigger this subsystem restart(SSR) 
>> at
>> any point of time
>> when a session is running. It's totally client-driven.
>> 
>> >>
>> >> Please feel free to correct me in case my understanding of the
>> >> framework
>> >> is wrong.
>> >>
>> >
>> > I presume the fault injection framework could get a new feature that
>> > lets the fault be injected immediately upon writing the debugfs file.
>> > My goal is to consolidate this sort of logic into one place and then
>> > put
>> > it behind some config option that distros can disable so the kernel
>> > isn't bloated with debug features that end users will never care about.
> 
> So you can modify fault injection framework to support direct injection
> instead of statistical failures?

I am not sure how to do that. Could you pls give me more info?
Also, how is this beneficial than using debugfs?