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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Andrzej Hajda' <andrzej.hajda@intel.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "intel-gfx@lists.freedesktop.org" <intel-gfx@lists.freedesktop.org>,
        "dri-devel@lists.freedesktop.org" <dri-devel@lists.freedesktop.org>
CC:     Jani Nikula <jani.nikula@linux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
        Andi Shyti <andi.shyti@linux.intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Arnd Bergmann <arnd@arndb.de>
Subject: RE: [PATCH 1/5] linux/minmax.h: add non-atomic version of xchg
Thread-Topic: [PATCH 1/5] linux/minmax.h: add non-atomic version of xchg
Thread-Index: AQHZC+X/n2yHksRnF0Csd/+tl8P8Ka5qAX6g
Date:   Mon, 12 Dec 2022 09:38:12 +0000
Message-ID: <f58ab17e5c6c4a4e8b0d687b44618c51@AcuMS.aculab.com>
References: <20221209154843.4162814-1-andrzej.hajda@intel.com>
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From: Andrzej Hajda <andrzej.hajda@intel.com>
> Sent: 09 December 2022 15:49
> 
> The pattern of setting variable with new value and returning old
> one is very common in kernel. Usually atomicity of the operation
> is not required, so xchg seems to be suboptimal and confusing in
> such cases. Since name xchg is already in use and __xchg is used
> in architecture code, proposition is to name the macro exchange.

Dunno, if it is non-atomic then two separate assignment statements
is decidedly more obvious and needs less brain cells to process.
Otherwise someone will assume 'something clever' is going on
and the operation is atomic.

	David

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