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From:   Eric Dumazet <edumazet@google.com>
Date:   Thu, 7 Oct 2021 07:13:13 -0700
Message-ID: <CANn89iLEz5POFii_=wU=2J0A9CE3H5JPq3sQFUQ8E400YumUpw@mail.gmail.com>
Subject: Re: [PATCH] x86/apic: reduce cache line misses in __x2apic_send_IPI_mask()
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Eric Dumazet <eric.dumazet@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Borislav Petkov <bp@suse.de>
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On Thu, Oct 7, 2021 at 7:07 AM Peter Zijlstra <peterz@infradead.org> wrote:
>
> On Thu, Oct 07, 2021 at 07:04:09AM -0700, Eric Dumazet wrote:
> > Good idea, I will try this.
> > Hopefully nr_cpu_ids is populated there ?
>
> Lets hope :-), I'm always terminally lost in early bringup. I figure it
> should be painfully obvious if it goes wrong.

The answer seems to be yes on hosts I tested.