From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751281AbeDYDXW (ORCPT ); Tue, 24 Apr 2018 23:23:22 -0400 Received: from mail-pf0-f194.google.com ([209.85.192.194]:39645 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751155AbeDYDXS (ORCPT ); Tue, 24 Apr 2018 23:23:18 -0400 X-Google-Smtp-Source: AIpwx4/XpGYDd5KWYKt1eu5V2IbSmPhe/Hd/wvvxf9Uqyt7lOVn/xx027YvbhN7/y+Xsla5R2K5DRg== To: linux-kernel@vger.kernel.org Cc: Marc Zyngier , tglx@linutronix.de, jason@lakedaemon.net, Catalin Marinas From: valmiki Subject: Affinity for GIC irq line Message-ID: <2880aee6-704c-a5aa-e193-75bba1bce43d@gmail.com> Date: Wed, 25 Apr 2018 08:53:09 +0530 User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, When an IRQ line is set affinity using irq_set_affinity, which calls irq_do_set_affinity, this API copies affinity mask to affinity variable in irq_common_data of this irq descriptor. But as per ARM GICv2 document in order to drive a interrupt to a specific CPU we need to program GICD_ITARGETSRn register. But irq_set_affinity isn't writing to this register.Please correct me if I'm wrong i did not find code for this register being updated in irq_set_affinity flow. So how affinity is being set for an IRQ line ? If affinity was set successfully on what CPU does asm_do_IRQ run ? For every interrupt this runs on CPU0 and then FIQ/IRQ handling is scheduled on different CPU as per affinity ? How the respective irq line handler is handled on specific CPU core ? Regards, Valmiki --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus