Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753585AbaFCHlJ (ORCPT ); Tue, 3 Jun 2014 03:41:09 -0400 Received: from e06smtp10.uk.ibm.com ([195.75.94.106]:34390 "EHLO e06smtp10.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753232AbaFCHlH (ORCPT ); Tue, 3 Jun 2014 03:41:07 -0400 Date: Tue, 3 Jun 2014 09:41:02 +0200 (CEST) From: Sebastian Ott X-X-Sender: sebott@denkbrett To: Fabian Frederick cc: linux-kernel , akpm Subject: Re: [PATCH 1/1] drivers/s390/cio/qdio_main.c: replace shift loop by ilog2 In-Reply-To: <20140602201757.66cf234bcba12078dc278eba@skynet.be> Message-ID: References: <20140520183728.c28374c3f1a655a2e33996a3@skynet.be> <20140602201757.66cf234bcba12078dc278eba@skynet.be> User-Agent: Alpine 2.11 (LFD 23 2013-08-11) Organization: =?ISO-8859-15?Q?=22IBM_Deutschland_Research_&_Development_GmbH_=2F_Vorsitzende_des_Aufsichtsrats=3A_Martina_Koederitz_Gesch=E4ftsf=FChrung=3A_Dirk_Wittkopp_Sitz_der_Gesellschaft=3A_B=F6blingen_=2F_Registergericht?= =?ISO-8859-15?Q?=3A_Amtsgericht_Stuttgart=2C_HRB_243294=22?= MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14060307-4966-0000-0000-0000003D2AE2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2 Jun 2014, Fabian Frederick wrote: > On Mon, 2 Jun 2014 16:41:48 +0200 (CEST) > Sebastian Ott wrote: > > > Hello Fabian, > > > > On Tue, 20 May 2014, Fabian Frederick wrote: > > > > > > This is untested. > > > > > > Cc: Sebastian Ott > > > Cc: Andrew Morton > > > Signed-off-by: Fabian Frederick > > > --- > > > drivers/s390/cio/qdio_main.c | 5 ++--- > > > 1 file changed, 2 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c > > > index 77466c4..8bf9ec1 100644 > > > --- a/drivers/s390/cio/qdio_main.c > > > +++ b/drivers/s390/cio/qdio_main.c > > > @@ -411,15 +411,14 @@ static inline void qdio_stop_polling(struct qdio_q *q) > > > > > > static inline void account_sbals(struct qdio_q *q, int count) > > > { > > > - int pos = 0; > > > + int pos; > > > > > > q->q_stats.nr_sbal_total += count; > > > if (count == QDIO_MAX_BUFFERS_MASK) { > > > q->q_stats.nr_sbals[7]++; > > > return; > > > } > > > - while (count >>= 1) > > > - pos++; > > > + pos = ilog2(count); > > > q->q_stats.nr_sbals[pos]++; > > > } > > > > > > -- > > > 1.8.4.5 > > > > > > > > > > Could you please resend the patch with a better description plus > > the change Joe suggested. > > > > Thanks, > > Sebastian > > Hello Sebastian, > Conclusion of that patch/thread was that callers guarantee count to be > 0 Correct. > Joe suggested to have unsigned count. Is it what you're talking about ? Yes. Regards, Sebastian -- 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/