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Subject: Re: [PATCH] sched: make struct task_struct::state 32-bit
To:     Alexey Dobriyan <adobriyan@gmail.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
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From:   Valentin Schneider <valentin.schneider@arm.com>
Message-ID: <64003dcd-d954-b76d-856a-214ff11ac000@arm.com>
Date:   Tue, 3 Sep 2019 17:31:46 +0100
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On 03/09/2019 17:23, Alexey Dobriyan wrote:
> 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.
> 

Yeah I figured, then had a minute of silence for those forsaken bytes.