From: Jeff Garzik <jgarzik@pobox.com>
To: Greg KH <greg@kroah.com>
Cc: Kristen Accardi <kristen.c.accardi@intel.com>,
linux-pci@atrey.karlin.mff.cuni.cz, linux-kernel@vger.kernel.org,
rajesh.shah@intel.com, akpm@osdl.org, torvalds@osdl.org
Subject: Re: [PATCH] 6700/6702PXH quirk
Date: Fri, 5 Aug 2005 23:34:55 -0400 [thread overview]
Message-ID: <20050806033455.GA23679@havoc.gtf.org> (raw)
In-Reply-To: <20050805225712.GD3782@kroah.com>
On Fri, Aug 05, 2005 at 03:57:12PM -0700, Greg KH wrote:
> Anyway, Jeff is right, add another bit field.
The updated patch, which adds a new bitfield, looks OK to me.
However...
<pedantic>
FWIW, compilers generate AWFUL code for bitfields. Bitfields are
really tough to do optimally, whereas bit flags ["unsigned int flags &
bitmask"] are the familiar ints and longs that the compiler is well
tuned to optimize.
Additionally, though it is not the case with struct pci_dev, bitfields
cause endian headaches (see the LITTLE_ENDIAN_BITFIELD ifdefs).
Bit flags are -far- superior in every case. Avoid bitfields like the plague.
</pedantic>
I wouldn't mind seeing a janitor remove all bitfields from struct pci_dev,
and any other kernel structure that uses the evil constructs.
Jeff
next prev parent reply other threads:[~2005-08-06 3:35 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-08-05 16:27 [PATCH] 6700/6702PXH quirk Kristen Accardi
2005-08-05 17:12 ` Bjorn Helgaas
2005-08-05 17:20 ` Kristen Accardi
2005-08-05 18:35 ` Greg KH
2005-08-05 19:10 ` Kristen Accardi
2005-08-05 22:05 ` Kristen Accardi
2005-08-05 22:26 ` Andrew Morton
2005-08-05 22:40 ` Kristen Accardi
2005-08-05 22:51 ` Andrew Morton
2005-08-05 22:57 ` Greg KH
2005-08-06 3:34 ` Jeff Garzik [this message]
2005-08-06 8:50 ` Matthew Wilcox
2005-08-06 15:57 ` Jeff Garzik
2005-08-07 15:46 ` Denis Vlasenko
2005-08-08 17:42 ` Zach Brown
2005-08-08 17:45 ` David S. Miller
2005-08-08 17:53 ` Zach Brown
2005-08-05 22:50 ` Jeff Garzik
2005-08-05 23:51 ` Kristen Accardi
2005-08-08 16:36 ` Bjorn Helgaas
2005-08-08 17:57 ` Kristen Accardi
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=20050806033455.GA23679@havoc.gtf.org \
--to=jgarzik@pobox.com \
--cc=akpm@osdl.org \
--cc=greg@kroah.com \
--cc=kristen.c.accardi@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@atrey.karlin.mff.cuni.cz \
--cc=rajesh.shah@intel.com \
--cc=torvalds@osdl.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox