From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E14F8C433EF for ; Mon, 28 Mar 2022 08:33:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239378AbiC1IfD (ORCPT ); Mon, 28 Mar 2022 04:35:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34836 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232858AbiC1Ie7 (ORCPT ); Mon, 28 Mar 2022 04:34:59 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 544FB12AC4; Mon, 28 Mar 2022 01:33:18 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A004DD6E; Mon, 28 Mar 2022 01:33:17 -0700 (PDT) Received: from [192.168.4.86] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5E3693F66F; Mon, 28 Mar 2022 01:33:15 -0700 (PDT) Message-ID: <7d571b9d-2066-8217-5485-da0e6ace65eb@arm.com> Date: Mon, 28 Mar 2022 09:33:10 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH v4 01/10] Use IDR to maintain all the enabled sources' paths. To: Jinlong Mao , Greg Kroah-Hartman Cc: Mathieu Poirier , Alexander Shishkin , Mike Leach , Leo Yan , coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Tingwei Zhang , Yuanfang Zhang , Tao Zhang , Trilok Soni , Hao Zhang , linux-arm-msm@vger.kernel.org References: <20220324121734.21531-1-quic_jinlmao@quicinc.com> <20220324121734.21531-2-quic_jinlmao@quicinc.com> From: Suzuki K Poulose In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 24/03/2022 14:23, Jinlong Mao wrote: > Hi Greg, > > Thanks for your review. > > On 3/24/2022 8:26 PM, Greg Kroah-Hartman wrote: >> On Thu, Mar 24, 2022 at 08:17:25PM +0800, Mao Jinlong wrote: >>> Use hash length of the source's device name to map to the pointer >>> of the enabled path. Using IDR will be more efficient than using >>> the list. And there could be other sources except STM and CPU etms >>> in the new HWs. It is better to maintain all the paths together. >>> >>> Signed-off-by: Mao Jinlong >>> --- >>>   drivers/hwtracing/coresight/coresight-core.c | 75 +++++++------------- >>>   1 file changed, 26 insertions(+), 49 deletions(-) >> Your subject line is odd.  Please put back the driver subsystem in the >> subject line so that it makes more sense. > I will update the subject in next version. >> >> And how have you measured "more efficient"? > > Using IDR would be better than doing a sequential search as there will > be much more device  in future. Where do we use sequential search now ? For non-CPU bound sources, yes we may need something. But CPU case is straight forward, and could be retained as it is. i.e., per-cpu list of paths. Cheers Suzuki > >> >> thanks, >> >> greg k-h > > Thanks > > Jinlong Mao >