checkpatch: consolidate if (foo) bar(foo) checks and add debugfs_remove

Consolidate the if (foo) bar(foo) detectors into a single check.  Add
debugfs_remove and family.

Based on a patch by Constantine Shulyupin.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Constantine Shulyupin <const@MakeLinux.com>.
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index d2d5ba1..a1b870d 100755 (executable)
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3198,20 +3198,12 @@ sub process {
                                $herecurr);
                }
 
-# check for needless kfree() checks
-               if ($prevline =~ /\bif\s*\(([^\)]*)\)/) {
-                       my $expr = $1;
-                       if ($line =~ /\bkfree\(\Q$expr\E\);/) {
-                               WARN("NEEDLESS_KFREE",
-                                    "kfree(NULL) is safe this check is probably not required\n" . $hereprev);
-                       }
-               }
-# check for needless usb_free_urb() checks
-               if ($prevline =~ /\bif\s*\(([^\)]*)\)/) {
-                       my $expr = $1;
-                       if ($line =~ /\busb_free_urb\(\Q$expr\E\);/) {
-                               WARN("NEEDLESS_USB_FREE_URB",
-                                    "usb_free_urb(NULL) is safe this check is probably not required\n" . $hereprev);
+# check for needless "if (<foo>) fn(<foo>)" uses
+               if ($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 this check is probably not required\n" . $hereprev);
                        }
                }