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Subject[PATCH] checkpatch: Add test for long udelay
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On Tue, 2014-02-04 at 08:03 +0100, Holger Schurig wrote:
> The macro udelay
> cannot handle large values because of lost-of-precision.
>
> IMHO udelay on ARM is broken, because it also cannot work with fast
> ARM processors (where bogomips >= 3355, which is in sight now). It's
> just not broken enought that someone did something against it ... so
> the current kludge is good enought.

Until then, warn on long udelay uses.

Also fix uses of $line that should have been $herecurr.

Signed-off-by: Joe Perches <joe@perches.com>
---
scripts/checkpatch.pl | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 0ea2a1e..36275c5 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3912,10 +3912,15 @@ sub process {

# prefer usleep_range over udelay
if ($line =~ /\budelay\s*\(\s*(\d+)\s*\)/) {
+ my $delay = $1;
# ignore udelay's < 10, however
- if (! ($1 < 10) ) {
+ if (! ($delay < 10) ) {
CHK("USLEEP_RANGE",
- "usleep_range is preferred over udelay; see Documentation/timers/timers-howto.txt\n" . $line);
+ "usleep_range is preferred over udelay; see Documentation/timers/timers-howto.txt\n" . $herecurr);
+ }
+ if ($delay > 2000) {
+ WARN("LONG_UDELAY",
+ "long udelay - prefer mdelay; see arch/arm/include/asm/delay.h\n" . $herecurr);
}
}

@@ -3923,7 +3928,7 @@ sub process {
if ($line =~ /\bmsleep\s*\((\d+)\);/) {
if ($1 < 20) {
WARN("MSLEEP",
- "msleep < 20ms can sleep for up to 20ms; see Documentation/timers/timers-howto.txt\n" . $line);
+ "msleep < 20ms can sleep for up to 20ms; see Documentation/timers/timers-howto.txt\n" . $herecurr);
}
}




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