Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752065Ab2KQRk4 (ORCPT ); Sat, 17 Nov 2012 12:40:56 -0500 Received: from perches-mx.perches.com ([206.117.179.246]:48306 "EHLO labridge.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752003Ab2KQRkz (ORCPT ); Sat, 17 Nov 2012 12:40:55 -0500 Message-ID: <1353174050.13961.5.camel@joe-AO722> Subject: Re: [PATCH v2] checkpatch: debugfs_remove() can take NULL From: Joe Perches To: Constantine Shulyupin Cc: linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org, Andy Whitcroft Date: Sat, 17 Nov 2012 09:40:50 -0800 In-Reply-To: <1353162965-575-1-git-send-email-const@MakeLinux.com> References: <1353162965-575-1-git-send-email-const@MakeLinux.com> Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.6.0-0ubuntu3 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3835 Lines: 113 On Sat, 2012-11-17 at 16:36 +0200, Constantine Shulyupin wrote: > From: Constantine Shulyupin > > debugfs_remove() and debugfs_remove_recursive() can take a NULL, so let's check and warn about that. > > Channegs since v1: > > - added debugfs_remove_recursivere > - all tests for pattenrs are "if (a) xxx(a)" are consolidates Hello Constantine. Just some trivia and a suggestion: There are a couple of typos in the commit message (I do that all the time myself) > Signed-off-by: Constantine Shulyupin > --- > scripts/checkpatch.pl | 16 ++++++++++++---- > 1 file changed, 12 insertions(+), 4 deletions(-) > > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl > index f18750e..2339b54 100755 > --- a/scripts/checkpatch.pl > +++ b/scripts/checkpatch.pl > @@ -3213,21 +3213,29 @@ sub process { > $herecurr); > } > > -# check for needless kfree() checks > +# check for needless "if" > if ($prevline =~ /\bif\s*\(([^\)]*)\)/) { > my $expr = $1; > +# check for needless kfree() checks > if ($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" . $hereprev); > } > +# check for needless debugfs_remove() checks > + if ($line =~ /\bdebugfs_remove\(\Q$expr\E\);/) { > + WARN("NEEDLESS_DEBUGFS_REMOVE", > + "debugfs_remove(NULL) is safe this check is probably not required\n" . $hereprev); > + } > +# check for needless debugfs_remove_recursive() checks > + if ($line =~ /\bdebugfs_remove_recursive\(\Q$expr\E\);/) { > + WARN("NEEDLESS_DEBUGFS_REMOVE", > + "debugfs_remove_recursive(NULL) is safe this check is probably not required\n" . $hereprev); > + } > } > > # prefer usleep_range over udelay Perhaps this is better because it allows whitespace around the check value: Right now this doesn't trigger, with the suggestion, it does. if ( foo ) kfree ( foo ); diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index d2d5ba1..c037c31 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3198,21 +3200,25 @@ sub process { $herecurr); } +# check for needless "if () fn()" uses + if ($prevline =~ /\bif\s*\(\s*($Lval)\s*\)/) { + my $expr = '\s*\(\s*' . quotemeta($1) . '\s*\)\s*;'; + # check for needless kfree() checks - if ($prevline =~ /\bif\s*\(([^\)]*)\)/) { - my $expr = $1; - if ($line =~ /\bkfree\(\Q$expr\E\);/) { + if ($line =~ /\bkfree$expr/) { 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\(\Q$expr\E\);/) { + if ($line =~ /\busb_free_urb$expr/) { WARN("NEEDLESS_USB_FREE_URB", "usb_free_urb(NULL) is safe this check is probably not required\n" . $hereprev); } +# check for needless debugfs_remove() and debugfs_remove_recursive*() checks + if ($line =~ /\b(debugfs_remove(?:_recursive)?)$expr/) { + WARN("NEEDLESS_DEBUGFS_REMOVE", + "$1(NULL) is safe this check is probably not required\n" . $hereprev); + } } # prefer usleep_range over udelay -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/