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Date:   Mon, 2 Dec 2019 17:21:52 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Andi Kleen <ak@linux.intel.com>
Cc:     kan.liang@linux.intel.com, mingo@redhat.com, acme@kernel.org,
        tglx@linutronix.de, bp@alien8.de, linux-kernel@vger.kernel.org,
        eranian@google.com, alexey.budankov@linux.intel.com,
        vitaly.slobodskoy@intel.com
Subject: Re: [RFC PATCH 3/8] perf: Init/fini PMU specific data
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On Mon, Dec 02, 2019 at 06:59:57AM -0800, Andi Kleen wrote:
> > 
> > This is atricous crap. Also it is completely broken for -RT.
> 
> Well can you please suggest how you would implement it instead?

I don't think that is on me; at best I get to explain why it is
completely unacceptible to have O(nr_tasks) and allocations under a
raw_spinlock_t, but I was thinking you'd already know that.