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Subject: Re: [PATCH RFC v6 16/21] dept: Distinguish each work from another
To:     Byungchul Park <byungchul.park@lge.com>,
        <torvalds@linux-foundation.org>
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References: <1651652269-15342-1-git-send-email-byungchul.park@lge.com>
 <1651652269-15342-17-git-send-email-byungchul.park@lge.com>
From:   Sergey Shtylyov <s.shtylyov@omp.ru>
Organization: Open Mobile Platform
Message-ID: <24e4d6db-9dc9-f113-f655-9af3a51723d4@omp.ru>
Date:   Wed, 4 May 2022 14:23:39 +0300
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Hello!

On 5/4/22 11:17 AM, Byungchul Park wrote:

> Workqueue already provides concurrency control. By that, any wait in a
> work doesn't prevents events in other works with the control enabled.
> Thus, each work would better be considered a different context.
> 
> So let Dept assign a different context id to each work.
> 
> Signed-off-by: Byungchul Park <byungchul.park@lge.com>
[...]
> diff --git a/kernel/dependency/dept.c b/kernel/dependency/dept.c
> index 18e5951..6707313 100644
> --- a/kernel/dependency/dept.c
> +++ b/kernel/dependency/dept.c
> @@ -1844,6 +1844,16 @@ void dept_enirq_transition(unsigned long ip)
>  	dept_exit(flags);
>  }
>  
> +/*
> + * Assign a different context id to each work.
> + */
> +void dept_work_enter(void)
> +{
> +	struct dept_task *dt = dept_task();
> +
> +	dt->cxt_id[DEPT_CXT_PROCESS] += (1UL << DEPT_CXTS_NR);

   Parens around << unnecessary...

[...]

MBR, Sergey