From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Mon, 12 Dec 2016 21:45:53 +0100 (CET) Received: from mailapp01.imgtec.com ([195.59.15.196]:6864 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S23993006AbcLLUpqj0JLS (ORCPT ); Mon, 12 Dec 2016 21:45:46 +0100 Received: from HHMAIL01.hh.imgtec.org (unknown [10.100.10.19]) by Forcepoint Email with ESMTPS id 1F4DCD5432B2C; Mon, 12 Dec 2016 20:45:36 +0000 (GMT) Received: from BAMAIL02.ba.imgtec.org (10.20.40.28) by HHMAIL01.hh.imgtec.org (10.100.10.19) with Microsoft SMTP Server (TLS) id 14.3.294.0; Mon, 12 Dec 2016 20:45:40 +0000 Received: from [10.20.2.61] (10.20.2.61) by bamail02.ba.imgtec.org (10.20.40.28) with Microsoft SMTP Server (TLS) id 14.3.266.1; Mon, 12 Dec 2016 12:45:38 -0800 Message-ID: <584F0C71.5010004@imgtec.com> Date: Mon, 12 Dec 2016 12:45:37 -0800 From: Leonid Yegoshin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: Florian Fainelli , Justin Chen CC: , , Justin Chen Subject: Re: [RFC] MIPS: Add cacheinfo support References: <20161208011626.20885-1-justinpopo6@gmail.com> <5849EC43.2070802@imgtec.com> <584A0281.3040505@imgtec.com> <3004fca6-3688-65bb-7c86-248603482088@gmail.com> In-Reply-To: <3004fca6-3688-65bb-7c86-248603482088@gmail.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.20.2.61] Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 56015 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: Leonid.Yegoshin@imgtec.com Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips On 12/12/2016 10:24 AM, Florian Fainelli wrote: > > What Justin's patch is about is not so much about providing hints to > user-space to bypass the kernel's own management of caches, (even though > that has been used as an argument by the original introduction of > cacheinfo), but more to provide some information to user-space about the > cache topology and hierarchy. I missed that, if it is for information purpose only, then it is OK. > > Even though this is limited information this is still helpful to > applications like lshw and others out there. > > What would be needed from your perspective to get cacheinfo added to > MIPS, shall we go back and address your initial comment about all the > little details about coherency, snooping and re-filling strategy? It depends. Initially, I thought Justin wants to replace arch/mips/mm/c-XXX.c with some universal approach and listed the missed stuff for that (I actually missed some more points in that list). But for information purpose I don't have any more addition to Justin's patch... may be the coherency status, it has impact on performance: coherency of L1D->L2, L2->memory and L1I->L1D/L2. - Leonid From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailapp01.imgtec.com ([195.59.15.196]:6864 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S23993006AbcLLUpqj0JLS (ORCPT ); Mon, 12 Dec 2016 21:45:46 +0100 Message-ID: <584F0C71.5010004@imgtec.com> Date: Mon, 12 Dec 2016 12:45:37 -0800 From: Leonid Yegoshin MIME-Version: 1.0 Subject: Re: [RFC] MIPS: Add cacheinfo support References: <20161208011626.20885-1-justinpopo6@gmail.com> <5849EC43.2070802@imgtec.com> <584A0281.3040505@imgtec.com> <3004fca6-3688-65bb-7c86-248603482088@gmail.com> In-Reply-To: <3004fca6-3688-65bb-7c86-248603482088@gmail.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Return-Path: Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-subscribe: List-owner: List-post: List-archive: To: Florian Fainelli , Justin Chen Cc: linux-mips@linux-mips.org, bcm-kernel-feedback-list@broadcom.com, Justin Chen Message-ID: <20161212204537.E0qPEYB-HbSbwFYvVGDdSzOrRjCYhChn9mVnR20Mn4o@z> On 12/12/2016 10:24 AM, Florian Fainelli wrote: > > What Justin's patch is about is not so much about providing hints to > user-space to bypass the kernel's own management of caches, (even though > that has been used as an argument by the original introduction of > cacheinfo), but more to provide some information to user-space about the > cache topology and hierarchy. I missed that, if it is for information purpose only, then it is OK. > > Even though this is limited information this is still helpful to > applications like lshw and others out there. > > What would be needed from your perspective to get cacheinfo added to > MIPS, shall we go back and address your initial comment about all the > little details about coherency, snooping and re-filling strategy? It depends. Initially, I thought Justin wants to replace arch/mips/mm/c-XXX.c with some universal approach and listed the missed stuff for that (I actually missed some more points in that list). But for information purpose I don't have any more addition to Justin's patch... may be the coherency status, it has impact on performance: coherency of L1D->L2, L2->memory and L1I->L1D/L2. - Leonid