From: Andi Kleen <andi@firstfloor.org>
To: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
Cc: tony.luck@intel.com, andi@firstfloor.org, bp@amd64.org,
gong.chen@linux.intel.com, ananth@in.ibm.com,
masbock@linux.vnet.ibm.com, x86@kernel.org,
linux-kernel@vger.kernel.org, lcm@us.ibm.com, mingo@redhat.com,
tglx@linutronix.de, linux-edac@vger.kernel.org
Subject: Re: [PATCH 1/2] x86/mce: Pack boolean MCE boot flags into a structure
Date: Mon, 27 Aug 2012 15:58:59 +0200 [thread overview]
Message-ID: <20120827135859.GY16230@one.firstfloor.org> (raw)
In-Reply-To: <20120827112503.10313.62594.stgit@localhost.localdomain>
On Mon, Aug 27, 2012 at 04:55:03PM +0530, Naveen N. Rao wrote:
> Many MCE boot flags are boolean in nature, but are declared as integers
> currently. We can pack these into a bitfield to save some space.
Note that this doesn't necessarily save anything because it needs more
code to access, and accesses are more common than the flag
cmpl $0,foo(%rip) 7 bytes
testl $1,foo(%rip) 10 bytes
bt $0,foo(%rip) 8 bytes
Even worse for writes. The best you can usually do is to use chars on
x86.
-Andi
next prev parent reply other threads:[~2012-08-27 13:59 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-27 11:25 [PATCH 1/2] x86/mce: Pack boolean MCE boot flags into a structure Naveen N. Rao
2012-08-27 11:25 ` [PATCH 2/2] x86/mce: Honour bios-set CMCI threshold Naveen N. Rao
2012-08-27 14:48 ` Borislav Petkov
2012-08-27 15:11 ` Naveen N. Rao
2012-08-27 15:21 ` Borislav Petkov
2012-08-27 13:58 ` Andi Kleen [this message]
2012-08-27 14:18 ` [PATCH 1/2] x86/mce: Pack boolean MCE boot flags into a structure Borislav Petkov
2012-08-28 6:55 ` Naveen N. Rao
2012-08-27 14:36 ` Borislav Petkov
2012-08-27 15:35 ` Naveen N. Rao
2012-08-27 15:47 ` Borislav Petkov
2012-08-27 16:01 ` Naveen N. Rao
2012-08-27 16:34 ` Borislav Petkov
2012-08-27 17:14 ` Naveen N. Rao
2012-08-27 20:18 ` Borislav Petkov
2012-08-28 7:17 ` Naveen N. Rao
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=20120827135859.GY16230@one.firstfloor.org \
--to=andi@firstfloor.org \
--cc=ananth@in.ibm.com \
--cc=bp@amd64.org \
--cc=gong.chen@linux.intel.com \
--cc=lcm@us.ibm.com \
--cc=linux-edac@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=masbock@linux.vnet.ibm.com \
--cc=mingo@redhat.com \
--cc=naveen.n.rao@linux.vnet.ibm.com \
--cc=tglx@linutronix.de \
--cc=tony.luck@intel.com \
--cc=x86@kernel.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.