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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Kent Overstreet' <kent.overstreet@gmail.com>
CC:     'Marcelo Ricardo Leitner' <marcelo.leitner@gmail.com>,
        "'linux-kernel@vger.kernel.org'" <linux-kernel@vger.kernel.org>,
        "'linux-sctp@vger.kernel.org'" <linux-sctp@vger.kernel.org>,
        'Eric Biggers' <ebiggers@kernel.org>,
        'Catalin Marinas' <catalin.marinas@arm.com>,
        "'Andrew Morton'" <akpm@linux-foundation.org>,
        'Neil Horman' <nhorman@tuxdriver.com>
Subject: RE: [PATCH 00/13] lib/generic-radix-tree: genradix bug fix and
 optimisations.
Thread-Topic: [PATCH 00/13] lib/generic-radix-tree: genradix bug fix and
 optimisations.
Thread-Index: AdZ67b0yl7qlbV/xQHyOe3+CAeHrEgAABLWAAAIsYaD///zZAP/+9nJQ//3Y1HA=
Date:   Wed, 26 Aug 2020 08:37:39 +0000
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From: David Laight
> Sent: 26 August 2020 08:36
...
> I'm going to try marking the lookup functions with '__attribute__ ((pure))'.
> That should help the sctp code that does repeated SCTP_SI().
> In reality I want to mark them __attribute__ ((const)) - including the
> inline wrappers, but that isn't allowed if they read memory.

Neither pure nor const makes any difference.
Even to code that like:
	if (SCTP_SO(...)->ext)
		SCTP_SO(...)->ext->foo = 0;

	David

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