From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [103.22.144.67]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 0292C1A07DB for ; Thu, 28 Jan 2016 19:28:45 +1100 (AEDT) Received: from mail-pa0-x231.google.com (mail-pa0-x231.google.com [IPv6:2607:f8b0:400e:c03::231]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 486C2140BA3 for ; Thu, 28 Jan 2016 19:28:44 +1100 (AEDT) Received: by mail-pa0-x231.google.com with SMTP id cy9so19662241pac.0 for ; Thu, 28 Jan 2016 00:28:44 -0800 (PST) Date: Thu, 28 Jan 2016 13:58:40 +0530 From: Viresh Kumar To: Shilpasri G Bhat Cc: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, rjw@rjwysocki.net, linux-pm@vger.kernel.org, pc@us.ibm.com, anton@samba.org, ego@linux.vnet.ibm.com, shreyas@linux.vnet.ibm.com, bsingharora@gmail.com, mpe@ellerman.id.au Subject: Re: [PATCH v7 3/6] cpufreq: powernv: Remove cpu_to_chip_id() from hot-path Message-ID: <20160128082840.GI3935@vireshk> References: <1453965941-7363-1-git-send-email-shilpa.bhat@linux.vnet.ibm.com> <1453965941-7363-4-git-send-email-shilpa.bhat@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1453965941-7363-4-git-send-email-shilpa.bhat@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 28-01-16, 12:55, Shilpasri G Bhat wrote: > cpu_to_chip_id() does a DT walk through to find out the chip id by > taking a contended device tree lock. This adds an unnecessary overhead > in a hot path. So instead of calling cpu_to_chip_id() everytime cache > the chip ids for all cores in the array 'core_to_chip_map' and use it > in the hotpath. > > Reported-by: Anton Blanchard > Signed-off-by: Shilpasri G Bhat > --- > Changes from v6: > - Minor changes to move the code 'cpumask_copy()' after 'core_to_chip_map' > is allocated. > - Move 'kfree(chips)' to a separate patch. See, you weren't that bad :) Just that you missed saying that individual patches contain version-log in cover-letter :) Acked-by: Viresh Kumar -- viresh