From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Matthew Wilcox <matthew@wil.cx>,
Linux Kernel list <linux-kernel@vger.kernel.org>,
linux-scsi <linux-scsi@vger.kernel.org>,
Russell King <rmk@arm.linux.org.uk>
Subject: Re: SCSI breakage on non-cache coherent architectures
Date: Tue, 20 Nov 2007 06:55:16 +1100 [thread overview]
Message-ID: <1195502116.6970.5.camel@pasglop> (raw)
In-Reply-To: <1195484964.3283.4.camel@localhost.localdomain>
> I'd like to be rid of it inside the command for various reasons: every
> command has one of these, and they're expensive in the allocation (at 96
> bytes). There's no reason we have to allocate and free that amount of
> space with every command. In theory, the number of these is bounded at
> the queue depth, in practice, there's usually only one, and this DMA
> alignment issue does requires most drivers to double copy.
Do you have a plan for short term here ? I'd like something fixed
for .25, so I may have to introduce a __dma_aligned macro of some sort
to deal with that in the meantime...
Ben.
next prev parent reply other threads:[~2007-11-19 19:55 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-11-19 5:35 SCSI breakage on non-cache coherent architectures Benjamin Herrenschmidt
2007-11-19 8:38 ` David Miller
2007-11-19 19:51 ` Benjamin Herrenschmidt
2007-11-19 22:31 ` David Miller
2007-11-20 0:34 ` Benjamin Herrenschmidt
2007-11-20 0:46 ` David Miller
2007-11-20 0:55 ` Benjamin Herrenschmidt
2007-11-20 0:57 ` David Miller
2007-11-20 2:10 ` Roland Dreier
2007-11-20 2:35 ` Benjamin Herrenschmidt
2007-11-20 3:14 ` Benjamin Herrenschmidt
2007-11-20 19:35 ` James Bottomley
2007-11-20 8:29 ` Thomas Bogendoerfer
2007-11-20 14:36 ` James Bottomley
2007-11-20 20:05 ` Roland Dreier
2007-11-20 21:10 ` James Bottomley
2007-11-20 22:39 ` Benjamin Herrenschmidt
2007-11-20 23:09 ` James Bottomley
2007-11-19 12:32 ` Matthew Wilcox
2007-11-19 15:09 ` James Bottomley
2007-11-19 19:54 ` Benjamin Herrenschmidt
2007-11-19 19:55 ` Benjamin Herrenschmidt [this message]
2007-11-19 19:53 ` Benjamin Herrenschmidt
2007-11-19 21:43 ` Roland Dreier
2007-11-19 21:55 ` Benjamin Herrenschmidt
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