checkpatch: add some <foo>_destroy functions to NEEDLESS_IF tests

Sergey Senozhatsky has modified several destroy functions that can
now be called with NULL values.

 - kmem_cache_destroy()
 - mempool_destroy()
 - dma_pool_destroy()

Update checkpatch to warn when those functions are preceded by an if.

Update checkpatch to --fix all the calls too only when the code style
form is using leading tabs.

from:
	if (foo)
		<func>(foo);
to:
	<func>(foo);

Signed-off-by: Joe Perches <joe@perches.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Joe Perches 2015-09-09 15:37:36 -07:00 committed by Linus Torvalds
parent 3e838b6c41
commit 100425deeb

View File

@ -4836,10 +4836,34 @@ sub process {
# check for needless "if (<foo>) fn(<foo>)" uses
if ($prevline =~ /\bif\s*\(\s*($Lval)\s*\)/) {
my $expr = '\s*\(\s*' . quotemeta($1) . '\s*\)\s*;';
if ($line =~ /\b(kfree|usb_free_urb|debugfs_remove(?:_recursive)?)$expr/) {
WARN('NEEDLESS_IF',
"$1(NULL) is safe and this check is probably not required\n" . $hereprev);
my $tested = quotemeta($1);
my $expr = '\s*\(\s*' . $tested . '\s*\)\s*;';
if ($line =~ /\b(kfree|usb_free_urb|debugfs_remove(?:_recursive)?|(?:kmem_cache|mempool|dma_pool)_destroy)$expr/) {
my $func = $1;
if (WARN('NEEDLESS_IF',
"$func(NULL) is safe and this check is probably not required\n" . $hereprev) &&
$fix) {
my $do_fix = 1;
my $leading_tabs = "";
my $new_leading_tabs = "";
if ($lines[$linenr - 2] =~ /^\+(\t*)if\s*\(\s*$tested\s*\)\s*$/) {
$leading_tabs = $1;
} else {
$do_fix = 0;
}
if ($lines[$linenr - 1] =~ /^\+(\t+)$func\s*\(\s*$tested\s*\)\s*;\s*$/) {
$new_leading_tabs = $1;
if (length($leading_tabs) + 1 ne length($new_leading_tabs)) {
$do_fix = 0;
}
} else {
$do_fix = 0;
}
if ($do_fix) {
fix_delete_line($fixlinenr - 1, $prevrawline);
$fixed[$fixlinenr] =~ s/^\+$new_leading_tabs/\+$leading_tabs/;
}
}
}
}