[PATCH] checkpatch: Add printk_once and printk_ratelimit to prefer pr_<level> warning

From: Joe Perches
Date: Wed Dec 09 2020 - 02:11:01 EST


Add the _once and _ratelimited variants to the test for
printk(KERN_<LEVEL> that should prefer pr_<level>.

Miscellanea:

o Add comment description for the conversions

Signed-off-by: Joe Perches <joe@xxxxxxxxxxx>
---
scripts/checkpatch.pl | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 7b086d1cd6c2..52f467fd32f9 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -4543,16 +4543,22 @@ sub process {
"printk() should include KERN_<LEVEL> facility level\n" . $herecurr);
}

- if ($line =~ /\bprintk\s*\(\s*KERN_([A-Z]+)/) {
- my $orig = $1;
+# prefer variants of (subsystem|netdev|dev|pr)_<level> to printk(KERN_<LEVEL>
+ if ($line =~ /\b(printk(_once|_ratelimited)?)\s*\(\s*KERN_([A-Z]+)/) {
+ my $printk = $1;
+ my $modifier = $2;
+ my $orig = $3;
my $level = lc($orig);
$level = "warn" if ($level eq "warning");
my $level2 = $level;
$level2 = "dbg" if ($level eq "debug");
+ $level .= $modifier;
+ $level2 .= $modifier;
WARN("PREFER_PR_LEVEL",
- "Prefer [subsystem eg: netdev]_$level2([subsystem]dev, ... then dev_$level2(dev, ... then pr_$level(... to printk(KERN_$orig ...\n" . $herecurr);
+ "Prefer [subsystem eg: netdev]_$level2([subsystem]dev, ... then dev_$level2(dev, ... then pr_$level(... to $printk(KERN_$orig ...\n" . $herecurr);
}

+# prefer dev_<level> to dev_printk(KERN_<LEVEL>
if ($line =~ /\bdev_printk\s*\(\s*KERN_([A-Z]+)/) {
my $orig = $1;
my $level = lc($orig);