All of lore.kernel.org
 help / color / mirror / Atom feed
From: Anton Blanchard <anton@samba.org>
To: Matthew Wilcox <willy@debian.org>
Cc: davidm@hpl.hp.com, linux-ia64@vger.kernel.org,
	linux-scsi@vger.kernel.org
Subject: Re: bogus barriers in sym53c8xx_2?
Date: Wed, 20 Aug 2003 13:43:18 +1000	[thread overview]
Message-ID: <20030820034318.GC25341@krispykreme> (raw)
In-Reply-To: <20030820032611.GI19630@parcelfarce.linux.theplanet.co.uk>


> I'm sure Gerard must have written it originally.  It's there
> in the earliest version of the sym2 driver I can find --
> sym-2.1.16a-for-linux-2.4.13.patch.gz.  A similar barrier is there in
> the sym1 driver (drivers/scsi/sym53c8xx_defs.h).  It seems to have been
> introduced around 2.4.3 (symbios driver version 1.6b -> 1.7.3a-20010304)
> 
> So you're looking for a patch which looks something like this:
> 
> - #define __READ_BARRIER()	__asm__ volatile("mf.a; mf" : : : "memory")
> - #define __WRITE_BARRIER()	__asm__ volatile("mf.a; mf" : : : "memory")
> + #define __READ_BARRIER()	__asm__ volatile("mf" : : : "memory")
> + #define __WRITE_BARRIER()	__asm__ volatile("mf" : : : "memory")
> 
> Or really, might be better to just define them to rmb() and wmb()?

I suspect so, the powerpc ones are overkill too:

#define __READ_BARRIER()        __asm__ volatile("eieio; sync" : : : "memory")
#define __WRITE_BARRIER()       __asm__ volatile("eieio; sync" : : : "memory")

Anton

  reply	other threads:[~2003-08-20  3:47 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <200308192349.h7JNnrEK017626@napali.hpl.hp.com>
2003-08-20  3:26 ` bogus barriers in sym53c8xx_2? Matthew Wilcox
2003-08-20  3:43   ` Anton Blanchard [this message]
2003-08-21 19:34     ` David Mosberger
2003-08-19 23:49 David Mosberger
2003-08-20  3:26 ` Matthew Wilcox
2003-08-20  3:43 ` Anton Blanchard
2003-08-21 19:34 ` David Mosberger

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20030820034318.GC25341@krispykreme \
    --to=anton@samba.org \
    --cc=davidm@hpl.hp.com \
    --cc=linux-ia64@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=willy@debian.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.