From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [dm-devel] [PATCH] sched: make struct task_struct::state 32-bit
Date: Mon, 2 Sep 2019 23:51:55 -0700
Message-ID: <20190903065155.GA28322@infradead.org>
References: <20190902210558.GA23013@avx2>
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To: Alexey Dobriyan <adobriyan@gmail.com>
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On Tue, Sep 03, 2019 at 12:05:58AM +0300, Alexey Dobriyan wrote:
> 32-bit accesses are shorter than 64-bit accesses on x86_64.
> Nothing uses 64-bitness of ->state.
> 
> Space savings are ~2KB on F30 kernel config.

I guess we'd save even more when moving from a volatile to
WRITE_ONCE/READ_ONCE..