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Date:   Thu, 1 Sep 2022 08:51:31 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Suren Baghdasaryan <surenb@google.com>
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Subject: Re: [RFC PATCH 03/30] Lazy percpu counters
Message-ID: <YxBWczNCbZbj+reQ@hirez.programming.kicks-ass.net>
References: <20220830214919.53220-1-surenb@google.com>
 <20220830214919.53220-4-surenb@google.com>
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On Tue, Aug 30, 2022 at 02:48:52PM -0700, Suren Baghdasaryan wrote:
> +static void lazy_percpu_counter_switch_to_pcpu(struct raw_lazy_percpu_counter *c)
> +{
> +	u64 __percpu *pcpu_v = alloc_percpu_gfp(u64, GFP_ATOMIC|__GFP_NOWARN);

Realize that this is incorrect when used under a raw_spinlock_t.