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From: David Laight <David.Laight@ACULAB.COM>
To: "'Neil Horman'" <nhorman@tuxdriver.com>,
        Denys Vlasenko <dvlasenk@redhat.com>
CC: "David S. Miller" <davem@davemloft.net>,
        Vlad Yasevich <vyasevich@gmail.com>,
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Subject: RE: [PATCH v2] net: sctp: Don't use 64 kilobyte lookup table for
 four elements
Thread-Topic: [PATCH v2] net: sctp: Don't use 64 kilobyte lookup table for
 four elements
Thread-Index: AQHQ+fS9coWJP1VXkEmk/KIB4r2oOp5R+reA
Date: Mon, 28 Sep 2015 14:12:26 +0000
Message-ID: <063D6719AE5E284EB5DD2968C1650D6D1CBA41B0@AcuExch.aculab.com>
References: <1443443644-12825-1-git-send-email-dvlasenk@redhat.com>
 <20150928135127.GB5248@hmsreliant.think-freely.org>
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From: Neil Horman
> Sent: 28 September 2015 14:51
> On Mon, Sep 28, 2015 at 02:34:04PM +0200, Denys Vlasenko wrote:
> > Seemingly innocuous sctp_trans_state_to_prio_map[] array
> > is way bigger than it looks, since
> > "[SCTP_UNKNOWN] = 2" expands into "[0xffff] = 2" !
> >
> > This patch replaces it with switch() statement.

What about just adding 1 (and masking) before indexing the array?
That might require a static inline function with a local static array.

Or define the array as (say) [16] and just mask the state before using
it as an index?

	David