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Date: Mon, 15 Jun 2015 18:25:25 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, arnd@arndb.de,
        Alexey Brodkin <Alexey.Brodkin@synopsys.com>,
        arc-linux-dev@synopsys.com, Arnaldo Carvalho de Melo <acme@kernel.org>
Subject: Re: [PATCH 4/8] ARCv2: perf: Support sampling events using overflow
 interrupts
Message-ID: <20150615162525.GH3644@twins.programming.kicks-ass.net>
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On Tue, Jun 09, 2015 at 05:49:28PM +0530, Vineet Gupta wrote:
> +	if (arc_pmu->has_interrupts) {
> +		int irq = platform_get_irq(pdev, 0);

Hmm, so you're requesting a regular interrupt.

I see your architecture has IRQ priorities, could you play games and
create NMIs using those?

For example, never mask L1 (assuming that's the highest priority) and
treat that as an NMI.