Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752638Ab0HKNLp (ORCPT ); Wed, 11 Aug 2010 09:11:45 -0400 Received: from mailbigip.dreamhost.com ([208.97.132.5]:35557 "EHLO homiemail-a1.g.dreamhost.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752581Ab0HKNLn (ORCPT ); Wed, 11 Aug 2010 09:11:43 -0400 Subject: Re: [PATCH] jbd: Remove redundant NULL check upon kfree() From: Davidlohr Bueso Reply-To: dave@gnu.org To: Jiri Kosina Cc: Andrew Morton , linux-fsdevel@vger.kernel.org, LKML In-Reply-To: References: <1281531654.2067.2.camel@cowboy> Content-Type: text/plain; charset="UTF-8" Date: Wed, 11 Aug 2010 09:11:37 -0400 Message-ID: <1281532297.2067.8.camel@cowboy> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1311 Lines: 38 On Wed, 2010-08-11 at 15:06 +0200, Jiri Kosina wrote: > On Wed, 11 Aug 2010, Davidlohr Bueso wrote: > > > jbd: Remove redundant NULL check upon kfree(). > > > > Signed-off-by: Davidlohr Bueso > > --- > > fs/jbd/transaction.c | 3 +-- > > 1 files changed, 1 insertions(+), 2 deletions(-) > > > > diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c > > index 5ae71e7..5e98130 100644 > > --- a/fs/jbd/transaction.c > > +++ b/fs/jbd/transaction.c > > @@ -232,8 +232,7 @@ repeat_locked: > > > > lock_map_acquire(&handle->h_lockdep_map); > > out: > > - if (unlikely(new_transaction)) /* It's usually NULL */ > > - kfree(new_transaction); > > + kfree(new_transaction); > > This doesn't seem entirely redundant, as it is optimized (via the > unlikely() hint) for the opposite case than what kfree() is optimized for > (kfree() assumes that the pointer is likely non-NULL, while the code above > assumes that the pointer si likely NULL). > Ok, makes sense. I was a bit doubtful about the unlikely(), thanks for the review. Davidlohr -- 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/