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Date:   Tue, 3 Sep 2019 19:23:03 +0300
From:   Alexey Dobriyan <adobriyan@gmail.com>
To:     Valentin Schneider <valentin.schneider@arm.com>
Cc:     mingo@redhat.com, peterz@infradead.org,
        linux-kernel@vger.kernel.org, rcu@vger.kernel.org,
        linux-block@vger.kernel.org, dm-devel@redhat.com, axboe@kernel.dk,
        aarcange@redhat.com
Subject: Re: [PATCH] sched: make struct task_struct::state 32-bit
Message-ID: <20190903162303.GA2173@avx2>
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 <7b94004e-4a65-462b-cd6b-5cbd23d607bf@arm.com>
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On Tue, Sep 03, 2019 at 12:02:38AM +0100, Valentin Schneider wrote:
> struct task_struct {
> 	struct thread_info         thread_info;          /*     0    24 */
> 	volatile int               state;                /*    24     4 */
> 
> 	/* XXX 4 bytes hole, try to pack */
> 
> 	void *                     stack;                /*    32     8 */
> 
> Though seeing as this is also the boundary of the randomized layout we can't
> really do much better without changing the boundary itself. So much for
> cacheline use :/

Cacheline use of task_struct is pretty hopeless because of all the ifdefs.