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From: Jani Nikula <jani.nikula@linux.intel.com>
To: David Laight <David.Laight@ACULAB.COM>, "'linux-kernel@vger.kernel.org'"
 <linux-kernel@vger.kernel.org>, 'Linus
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Cc: 'Jens Axboe' <axboe@kernel.dk>, "'Matthew Wilcox (Oracle)'"
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 <davem@davemloft.net>, 'Dan Carpenter' <dan.carpenter@linaro.org>
Subject: RE: [PATCH next 10/11] block: Use a boolean expression instead of
 max() on booleans
In-Reply-To: <963d1126612347dd8c398a9449170e16@AcuMS.aculab.com>
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Date: Mon, 29 Jan 2024 11:47:37 +0200
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On Mon, 29 Jan 2024, David Laight <David.Laight@ACULAB.COM> wrote:
> From: Jani Nikula
>> Sent: 29 January 2024 09:08
>> 
>> On Sun, 28 Jan 2024, David Laight <David.Laight@ACULAB.COM> wrote:
>> > blk_stack_limits() contains:
>> > 	t->zoned = max(t->zoned, b->zoned);
>> > These are bool, so it is just a bitwise or.
>> 
>> Should be a logical or, really. And || in code.
>
> Not really, bitwise is fine for bool (especially for 'or')
> and generates better code.

Logical operations for booleans are more readable for humans than
bitwise. And semantically correct.

With a = b || c you know what happens regardless of the types in
question. a = b | c you have to look up the types to know what's going
on.

To me, better code only matters if it's a hotpath.

That said, not my are of maintenance, so *shrug*.


BR,
Jani.


-- 
Jani Nikula, Intel