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From:   Kent Overstreet <kent.overstreet@linux.dev>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Suren Baghdasaryan <surenb@google.com>, akpm@linux-foundation.org,
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Subject: Re: [RFC PATCH 03/30] Lazy percpu counters
Message-ID: <20220901143219.n7jg7cbp47agqnwn@moria.home.lan>
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On Thu, Sep 01, 2022 at 08:51:31AM +0200, Peter Zijlstra wrote:
> 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.

Can you elaborate?