From mboxrd@z Thu Jan 1 00:00:00 1970 From: julien.thierry@arm.com (Julien Thierry) Date: Mon, 30 Apr 2018 10:53:17 +0100 Subject: [PATCH v2 0/6] arm64: provide pseudo NMI with GICv3 In-Reply-To: References: <1516190084-18978-1-git-send-email-julien.thierry@arm.com> Message-ID: <07a0b8c1-3d87-0cae-61df-dbff782be301@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 29/04/18 07:37, Joel Fernandes wrote: > On Wed, Jan 17, 2018 at 4:10 AM, Julien Thierry wrote: >> Hi, >> >> On 17/01/18 11:54, Julien Thierry wrote: >>> >>> This series is a continuation of the work started by Daniel [1]. The goal >>> is to use GICv3 interrupt priorities to simulate an NMI. >>> >> >> >> I have submitted a separate series making use of this feature for the ARM >> PMUv3 interrupt [1]. > > I guess the hard lockup detector using NMI could be a nice next step > to see how well it works with lock up detection. That's the main > usecase for my interest. However, perf profiling is also a strong one. > From my understanding, Linux's hardlockup detector already uses the ARM PMU interrupt to check whether some task is stuck. I haven't looked at the details of the implementation yet, but in theory having the PMU interrupt as NMI should make the hard lockup detector use the NMI. When I do the v3, I'll have a look at this to check whether the hardlockup detector works fine when using NMI. Cheers, -- Julien Thierry