Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933200AbbBBM7Z (ORCPT ); Mon, 2 Feb 2015 07:59:25 -0500 Received: from cmexedge1.emulex.com ([138.239.224.99]:9634 "EHLO CMEXEDGE1.ext.emulex.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754009AbbBBM7W (ORCPT ); Mon, 2 Feb 2015 07:59:22 -0500 From: Selvin Xavier To: Yann Droneaud , Rasmus Villemoes CC: Roland Dreier , Sean Hefty , Hal Rosenstock , "linux-rdma@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Devesh Sharma , Mitesh Ahuja Subject: RE: [PATCH 1/2] infiniband: Help gcc generate better code for ocrdma_srq_toggle_bit Thread-Topic: [PATCH 1/2] infiniband: Help gcc generate better code for ocrdma_srq_toggle_bit Thread-Index: AQHQMZpd7Bs1LnyVI0GStbUR4d3ZhpzZXdx0gAFRVACAAq7HQA== Date: Mon, 2 Feb 2015 12:58:44 +0000 Message-ID: References: <1421419196-4659-1-git-send-email-linux@rasmusvillemoes.dk> <87twz7ho25.fsf@rasmusvillemoes.dk> <1422702466.3030.4.camel@opteya.com> In-Reply-To: <1422702466.3030.4.camel@opteya.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.226.192.248] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by nfs id t12CxUEj003082 Content-Length: 2759 Lines: 77 Thank you Yann Droneaud for forwarding this mail. We will add an entry for ocrdma driver in MAINTAINERS file. Thanks, Selvin Xavier > -----Original Message----- > From: Yann Droneaud [mailto:ydroneaud@opteya.com] > Sent: Saturday, January 31, 2015 4:38 PM > To: Rasmus Villemoes > Cc: Roland Dreier; Sean Hefty; Hal Rosenstock; linux-rdma@vger.kernel.org; > linux-kernel@vger.kernel.org; Devesh Sharma; Selvin Xavier; Mitesh Ahuja > Subject: Re: [PATCH 1/2] infiniband: Help gcc generate better code for > ocrdma_srq_toggle_bit > > Hi, > > Le samedi 31 janvier 2015 à 00:00 +0100, Rasmus Villemoes a écrit : > > ping > > > > As you're fixing ocrdma driver, I think you might want to find people > @emulex.com to review your patches. > > BTW, there's no MAINTAINERS entry for ocrdma driver ... which is a pity. > > > On Fri, Jan 16 2015, Rasmus Villemoes wrote: > > > > > gcc emits a surprising amount of code in order to flip a bit. One > > > would think that a single instruction is enough. > > > > > > $ scripts/bloat-o-meter /tmp/ocrdma_verbs.o > > > drivers/infiniband/hw/ocrdma/ocrdma_verbs.o > > > add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-142 (-142) > > > function old new delta > > > ocrdma_post_srq_recv 498 460 -38 > > > ocrdma_poll_cq 2010 1962 -48 > > > ocrdma_discard_cqes 495 439 -56 > > > > > > All three calls of ocrdma_srq_toggle_bit happen within spinlocks, so > > > saving a few useless instructions might be worthwhile. > > > > > > Signed-off-by: Rasmus Villemoes > > > --- > > > drivers/infiniband/hw/ocrdma/ocrdma_verbs.c | 5 +---- > > > 1 file changed, 1 insertion(+), 4 deletions(-) > > > > > > diff --git a/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c > > > b/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c > > > index fb8d8c4dfbb9..eff11e6c6183 100644 > > > --- a/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c > > > +++ b/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c > > > @@ -1484,10 +1484,7 @@ static void ocrdma_srq_toggle_bit(struct > ocrdma_srq *srq, int idx) > > > int i = idx / 32; > > > unsigned int mask = (1 << (idx % 32)); > > > > > > - if (srq->idx_bit_fields[i] & mask) > > > - srq->idx_bit_fields[i] &= ~mask; > > > - else > > > - srq->idx_bit_fields[i] |= mask; > > > + srq->idx_bit_fields[i] ^= mask; > > > } > > > > > > static int ocrdma_hwq_free_cnt(struct ocrdma_qp_hwq_info *q) > > -- > > Regards. > > -- > Yann Droneaud > OPTEYA > > ????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m???? ????????I?