From: robherring2@gmail.com (Rob Herring)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] ARM: enable CONFIG_KTIME_SCALAR
Date: Tue, 1 Mar 2011 12:38:06 -0600 [thread overview]
Message-ID: <1299004686-9281-1-git-send-email-robherring2@gmail.com> (raw)
From: Rob Herring <rob.herring@calxeda.com>
Use straight 64-bit values as 64-bit operations are fairly efficient on ARM.
Comparing the asm output with and without KTIME_SCALAR, using 64-bit math
generates clearly better code.
Comparing kernel/hrtimer.c .text size, it goes from 0x1414 to 0x119c with
this change.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
---
arch/arm/Kconfig | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 166efa2..0efbea4 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -63,6 +63,10 @@ config GENERIC_CLOCKEVENTS_BROADCAST
depends on GENERIC_CLOCKEVENTS
default y if SMP
+config KTIME_SCALAR
+ bool
+ default y
+
config HAVE_TCM
bool
select GENERIC_ALLOCATOR
--
1.7.1
reply other threads:[~2011-03-01 18:38 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=1299004686-9281-1-git-send-email-robherring2@gmail.com \
--to=robherring2@gmail.com \
--cc=linux-arm-kernel@lists.infradead.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;
as well as URLs for NNTP newsgroup(s).