netdev - [PATCH next v2 10/11] block: Use a boolean expression instead of max() on booleans

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Message-ID: <9561641946f1404b931d97a576bfbb28@AcuMS.aculab.com>
Date: Sun, 25 Feb 2024 16:56:16 +0000
From: David Laight <David.Laight@...LAB.COM>
To: "'linux-kernel@...r.kernel.org'" <linux-kernel@...r.kernel.org>, "'Linus
 Torvalds'" <torvalds@...ux-foundation.org>, 'Netdev'
	<netdev@...r.kernel.org>, "'dri-devel@...ts.freedesktop.org'"
	<dri-devel@...ts.freedesktop.org>
CC: 'Jens Axboe' <axboe@...nel.dk>, "'Matthew Wilcox (Oracle)'"
	<willy@...radead.org>, 'Christoph Hellwig' <hch@...radead.org>,
	"'linux-btrfs@...r.kernel.org'" <linux-btrfs@...r.kernel.org>, "'Andrew
 Morton'" <akpm@...ux-foundation.org>, 'Andy Shevchenko'
	<andriy.shevchenko@...ux.intel.com>, "'David S . Miller'"
	<davem@...emloft.net>, 'Dan Carpenter' <dan.carpenter@...aro.org>, "'Jani
 Nikula'" <jani.nikula@...ux.intel.com>
Subject: [PATCH next v2 10/11] block: Use a boolean expression instead of
 max() on booleans

blk_stack_limits() contains:
	t->zoned = max(t->zoned, b->zoned);
These are bool, so can be replaced by bitwise or.
However it generates:
error: comparison of constant '0' with boolean expression is always true [-Werror=bool-compare]
inside the signedness check that max() does unless a '+ 0' is added.
It is a shame the compiler generates this warning for code that will
be optimised away.

Change so that the extra '+ 0' can be removed.

Signed-off-by: David Laight <david.laight@...lab.com>
---
 block/blk-settings.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Changes for v2:
- Typographical and spelling corrections to the commit messages.
  Patches unchanged.

diff --git a/block/blk-settings.c b/block/blk-settings.c
index 06ea91e51b8b..9ca21fea039d 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -688,7 +688,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
 						   b->max_secure_erase_sectors);
 	t->zone_write_granularity = max(t->zone_write_granularity,
 					b->zone_write_granularity);
-	t->zoned = max(t->zoned, b->zoned);
+	t->zoned = t->zoned | b->zoned;
 	return ret;
 }
 EXPORT_SYMBOL(blk_stack_limits);
-- 
2.17.1

-
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