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Date: Fri, 23 Sep 2016 09:21:17 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Nicolai Stange <nicstange@gmail.com>
Cc: Juergen Gross <jgross@suse.com>, Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Davidlohr Bueso <dave@stgolabs.net>,
        Richard Weinberger <richard@nod.at>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] smp: smp_call_on_cpu(): use INIT_WORK_ONSTACK() for
 automatic work_struct
Message-ID: <20160923072117.GK2794@worktop>
References: <20160922181758.3449-1-nicstange@gmail.com>
 <20160922184415.GB5012@twins.programming.kicks-ass.net>
 <87mviz7nkn.fsf@gmail.com>
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On Thu, Sep 22, 2016 at 09:15:52PM +0200, Nicolai Stange wrote:

> One minor question regarding your patch though: it hasn't got a
> destroy_work_on_stack(). Isn't one needed because of
>   INIT_WORK_ONSTACK() -> __INIT_WORK() -> __init_work() ->
>   debug_object_init_on_stack() ?
> At least work_on_cpu() destroys its local work_struct that way...

I wasn't aware of destroy_work_on_stack(), and I'm not familiar enough
with the debug objects stuff to see hwo important it is to call.

Also, there's more INIT_WORK_ONSTACK usage lacking
destroy_work_on_stack() calls.

Maybe it would be good to do a patch fixing them all up and adding a
comment with INIT_WORK_ONSTACK() that says it ought to be paired with
destroy_work_on_stack().