From mboxrd@z Thu Jan 1 00:00:00 1970 From: sboyd@codeaurora.org (Stephen Boyd) Date: Fri, 13 Feb 2015 16:01:43 -0800 Subject: [PATCH v2] ARM: smp: Only expose /sys/.../cpuX/online if hotpluggable In-Reply-To: <20150213230137.GH8656@n2100.arm.linux.org.uk> References: <1423850799-4028-1-git-send-email-sboyd@codeaurora.org> <20150213202002.GB29727@verge.net.au> <54DE5D3A.5070104@codeaurora.org> <54DE65C6.8000304@codeaurora.org> <20150213230137.GH8656@n2100.arm.linux.org.uk> Message-ID: <54DE9067.70103@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 02/13/15 15:01, Russell King - ARM Linux wrote: > On Fri, Feb 13, 2015 at 09:44:50PM +0000, Magnus Damm wrote: >> Also, based on the comment in mcpm_cpu_can_disable() it looks like the >> PSCI hook may be executed once only with your change in place? >> Hopefully PSCI is OK not being invoked for every CPU shutdown. > This is why I've said (in the parent thread) that I'm not happy to > apply this patch. Mark Rutland has indicated that he has MCPM cases > where the CPUs which can be disabled changes dynamically according > to the secure firmware requirements, and ripping out todays > infrastructure in light of that, only to have to add it back again > later makes no sense. Putting it back is not hard. And the infrastructure is not currently used for these purposes so renaming it is appropriate. I can leave it in place if you like, i.e. make a new op for cpu_can_disable and repoint mcpm's mcpm_cpu_disable() at it. Then when mcpm gets migrate support it can actually implement a cpu_disable op. > > However, cleaning things up by removing unnecessary cpu_disable > methods is a good thing to do irrespective of that. > That's fine I can split it out. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project