From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753409AbaIVIoP (ORCPT ); Mon, 22 Sep 2014 04:44:15 -0400 Received: from mail-by2on0125.outbound.protection.outlook.com ([207.46.100.125]:57248 "EHLO na01-by2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751058AbaIVIoO (ORCPT ); Mon, 22 Sep 2014 04:44:14 -0400 X-Greylist: delayed 992 seconds by postgrey-1.27 at vger.kernel.org; Mon, 22 Sep 2014 04:44:14 EDT Message-ID: <541FDD32.8020105@freescale.com> Date: Mon, 22 Sep 2014 11:26:26 +0300 From: Laurentiu Tudor User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.7.0 MIME-Version: 1.0 To: Scott Wood , Michael Neuling CC: , , , , , , , , , , "Laurentiu Tudor" Subject: Re: [PATCH 03/15] powerpc/msi: Improve IRQ bitmap allocator References: <1411028820-29933-1-git-send-email-mikey@neuling.org> <1411028820-29933-4-git-send-email-mikey@neuling.org> <1411157769.13320.74.camel@snotra.buserror.net> <1411157986.13320.75.camel@snotra.buserror.net> In-Reply-To: <1411157986.13320.75.camel@snotra.buserror.net> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [192.88.166.1] X-ClientProxiedBy: AM3PR01CA056.eurprd01.prod.exchangelabs.com (10.141.191.46) To BL2PR03MB305.namprd03.prod.outlook.com (10.141.68.13) X-Microsoft-Antispam: UriScan:; X-Microsoft-Antispam: BCL:0;PCL:0;RULEID:;SRVR:BL2PR03MB305; X-Forefront-PRVS: 034215E98F X-Forefront-Antispam-Report: SFV:NSPM;SFS:(10019020)(6009001)(377454003)(479174003)(24454002)(51704005)(189002)(199003)(377424004)(99396002)(66066001)(65806001)(50986999)(107046002)(19580405001)(83322001)(83506001)(15975445006)(19580395003)(65956001)(120916001)(85306004)(93886004)(76482002)(95666004)(59896002)(31966008)(97736003)(90102001)(81542003)(77096002)(79102003)(80022003)(74502003)(74662003)(50466002)(46102003)(81342003)(77982003)(33656002)(101416001)(87266999)(54356999)(102836001)(65816999)(76176999)(87976001)(85852003)(83072002)(42186005)(92726001)(80316001)(92566001)(105586002)(106356001)(21056001)(47776003)(4396001)(36756003)(23676002)(15202345003)(20776003)(64706001)(42262002);DIR:OUT;SFP:1102;SCL:1;SRVR:BL2PR03MB305;H:[10.171.73.112];FPR:;MLV:sfv;PTR:InfoNoRecords;MX:1;A:1;LANG:en; X-OriginatorOrg: freescale.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/19/2014 11:19 PM, Scott Wood wrote: > On Fri, 2014-09-19 at 15:16 -0500, Scott Wood wrote: >> On Thu, 2014-09-18 at 18:26 +1000, Michael Neuling wrote: >>> From: Ian Munsie >>> >>> Currently msi_bitmap_alloc_hwirqs() will round up any IRQ allocation requests >>> to the nearest power of 2. eg. ask for 5 IRQs and you'll get 8. This wastes a >>> lot of IRQs which can be a scarce resource. >>> >>> For cxl we can require multiple IRQs for every contexts that is attached to the >>> accelerator. For AFU directed accelerators, there may be 1000s of contexts >>> attached, hence we can easily run out of IRQs, especially if we are needlessly >>> wasting them. >>> >>> This changes the msi_bitmap_alloc_hwirqs() to allocate only the required number >>> of IRQs, hence avoiding this wastage. >>> >>> Signed-off-by: Ian Munsie >>> Signed-off-by: Michael Neuling >>> --- >>> arch/powerpc/sysdev/msi_bitmap.c | 18 +++++++++++++----- >>> 1 file changed, 13 insertions(+), 5 deletions(-) >> >> This conflicts with (and partially duplicates) >> http://patchwork.ozlabs.org/patch/381892/ >> which I have in my tree. How should we handle it? >> >> Laurentiu, from looking at the overlap between patches I see a problem >> with your existing patch, regarding the out-of-irqs path and >> msi_bitmap_free_hwirqs(), so one way or another that needs to get fixed >> soon. > > Given the problems with Laurentiu's patch, perhaps it'd be best for me > to just revert that patch in my tree, and respin it after this patchset > has been merged. Let me know if you want me to rebase my stuff on top of Michael's patch. --- Best Regards, Laurentiu