Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Tue, 09 Mar 2021 16:33:45 -0800
User-Agent: K-9 Mail for Android
In-Reply-To: <YEfnnFUbizbJUQig@hirez.programming.kicks-ass.net>
References: <YEepKVHc5kkDybu6@hirez.programming.kicks-ass.net> <20210309120519.7c6bbb97@gandalf.local.home> <YEfnnFUbizbJUQig@hirez.programming.kicks-ass.net>
MIME-Version: 1.0
Content-Type: text/plain;
 charset=utf-8
Content-Transfer-Encoding: quoted-printable
Subject: Re: The killing of ideal_nops[]
To:     Peter Zijlstra <peterz@infradead.org>,
        Steven Rostedt <rostedt@goodmis.org>
CC:     x86@kernel.org, linux-kernel@vger.kernel.org
From:   hpa@zytor.com
Message-ID: <362BD2A4-016D-4F6B-8974-92C84DC0DDB4@zytor.com>
Precedence: bulk

On March 9, 2021 1:24:44 PM PST, Peter Zijlstra <peterz@infradead=2Eorg> wr=
ote:
>On Tue, Mar 09, 2021 at 12:05:19PM -0500, Steven Rostedt wrote:
>> On Tue, 9 Mar 2021 17:58:17 +0100
>> Peter Zijlstra <peterz@infradead=2Eorg> wrote:
>>=20
>> > Hi,
>> >=20
>> > AFAICT everything made in the past 10 years ends up using p6_nops=2E
>Is it
>> > time to kill off ideal_nops[] and simplify life?
>> >=20
>>=20
>> Well, the one bug that was reported recently was due to a box that
>uses a
>> different "ideal_nops" than p6_nops=2E Perhaps we should ask him if
>there's
>> any noticeable difference between using p6_nops for every function
>than the
>> ideal_nops that as found for that box=2E
>
>If the machine is more than a decade old, I'm not really caring about
>optimal performance=2E If it is 32bit, I really couldn't be arsed as long
>as it boots=2E

p6_nops don't boot on all 32-bit chips=2E
--=20
Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E