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From: tip-bot for Patrick Pannuto on 4 Aug 2010 05:30
Commit-ID: 022d60db2ab6e97f93c98808d08fd883003048c7
Gitweb: http://git.kernel.org/tip/022d60db2ab6e97f93c98808d08fd883003048c7
Author: Patrick Pannuto <ppannuto(a)codeaurora.org>
AuthorDate: Mon, 2 Aug 2010 15:01:06 -0700
Committer: Thomas Gleixner <tglx(a)linutronix.de>
CommitDate: Wed, 4 Aug 2010 11:00:45 +0200

Checkpatch: Prefer usleep_range over udelay

When possible, sleeping is (usually) better than delaying;
however, don't bother callers of udelay < 10us, as those
cases are generally not worth the switch to usleep

Signed-off-by: Patrick Pannuto <ppannuto(a)codeaurora.org>
Cc: apw(a)canonical.com
Cc: corbet(a)lwn.net
Cc: arjan(a)linux.intel.com
Cc: Joe Perches <joe(a)perches.com>
Cc: Andrew Morton <akpm(a)linux-foundation.org>
LKML-Reference: <1280786467-26999-4-git-send-email-ppannuto(a)codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de>
---
scripts/checkpatch.pl | 8 ++++++++
1 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index bd88f11..1698c63 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2570,6 +2570,14 @@ sub process {
}
}

+# prefer usleep_range over udelay
+ if (($line =~ /\budelay\s*\(\s*(\w+)\s*\)/ {
+ # ignore udelay's < 10, however
+ if (! (($1 =~ /(\d+)/) && ($1 < 10)) ) {
+ CHK("usleep_range is preferred over udelay; see Documentation/timers/timers-howto.txt\n" . $line);
+ }
+ }
+
# warn about #ifdefs in C files
# if ($line =~ /^.\s*\#\s*if(|n)def/ && ($realfile =~ /\.c$/)) {
# print "#ifdef in C files should be avoided\n";
--
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Next: [tip:timers/core] Checkpatch: Warn about unexpectedly long msleep's