Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932388AbbDMOPi (ORCPT ); Mon, 13 Apr 2015 10:15:38 -0400 Received: from mail-wg0-f47.google.com ([74.125.82.47]:34763 "EHLO mail-wg0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932199AbbDMOPb (ORCPT ); Mon, 13 Apr 2015 10:15:31 -0400 Message-ID: <552BCEE6.6060003@linaro.org> Date: Mon, 13 Apr 2015 16:12:54 +0200 From: Eric Auger User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: Marc Zyngier , Abhijeet Dharmapurikar , Stephen Boyd , Phong Vo , Linus Walleij , Tin Huynh , Y Vo , Thomas Gleixner , Toan Le , Bjorn Andersson , Jason Cooper , Arnd Bergmann CC: linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v4 0/3] genirq: Saving/restoring the irqchip state of an irq line References: <1426676484-21812-1-git-send-email-marc.zyngier@arm.com> In-Reply-To: <1426676484-21812-1-git-send-email-marc.zyngier@arm.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3056 Lines: 81 Hi Marc, You can apply my R-b and T-b on the whole series. To be precise, I tested the get path only with my kvm-vfio forward series. Best Regards Eric Reviewed-by: Eric Auger Tested-by: Eric Auger On 03/18/2015 12:01 PM, Marc Zyngier wrote: > Despite Linux offering a rather fine grained control over the life > cycle of an interrupt, there is a few cases where it would be very > useful to snapshot (or even set) the internal state of the interrupt > controller for a given interrupt line: > > - With KVM, a device shared between VMs must have its whole context > switched, and that includes the interrupt line state. KVM/arm is > moving to using this. > - Some GPIO controllers seem to require peeking into the interrupt > controller they are connected to to report their internal state. > > Instead of letting people facing this situation doing horrible > (controller specific) hacks in their code, let's offer a couple of new > entry points that allow a few attributes to be read and set. > > Of course, this is a very dangerous thing to do if you don't know what > you doing, and I wouldn't expect most drivers to use this. But this > can also be a life saver at times. > > This patch series implement said API, and adds support for this to the > two main ARM interrupt controllers (GIC and GICv3). Available at: > > git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git irq/irqchip_state > > This has been fairly heavily tested with KVM on ARM, which makes use > of this feature to context switch the timer interrupt (see the last > three patch in the above branch). > > Thanks, > > M. > > * From v3 [3] > - Rebased on top of 4.0-rc4 > > * From v2 [2]: > - Rebased on top of 3.19-rc3 > - Fixed irq_set_irqchip_state return value > > * From v1 [1]: > - Rebased on top of 3.18-rc7 + tip/irq/irqdomain-arm > - Now deals with stacked domains > - Changed the API to be less ambiguous (after review by tglx) > - Added IRQCHIP_STATE_LINE_LEVEL (as requested by Bjorn Anderson) > > [1] https://lkml.org/lkml/2014/10/25/134 > [2] https://lkml.org/lkml/2014/12/3/612 > [3] http://lkml.iu.edu/hypermail/linux/kernel/1501.0/03473.html > > Marc Zyngier (3): > genirq: Allow the irqchip state of an IRQ to be save/restored > irqchip: GIC: Add support for irq_{get,set}_irqchip_state > irqchip: GICv3: Add support for irq_{get,set}_irqchip_state > > drivers/irqchip/irq-gic-v3.c | 83 +++++++++++++++++++++++++++++++++------- > drivers/irqchip/irq-gic.c | 69 +++++++++++++++++++++++++++++++-- > include/linux/interrupt.h | 14 +++++++ > include/linux/irq.h | 6 +++ > kernel/irq/manage.c | 91 ++++++++++++++++++++++++++++++++++++++++++++ > 5 files changed, 246 insertions(+), 17 deletions(-) > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/