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Date:   Tue, 12 Sep 2023 08:24:37 -0400
From:   Phil Auld <pauld@redhat.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Ankur Arora <ankur.a.arora@oracle.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org,
        akpm@linux-foundation.org, luto@kernel.org, bp@alien8.de,
        dave.hansen@linux.intel.com, hpa@zytor.com, mingo@redhat.com,
        juri.lelli@redhat.com, vincent.guittot@linaro.org,
        willy@infradead.org, mgorman@suse.de, rostedt@goodmis.org,
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        raghavendra.kt@amd.com, boris.ostrovsky@oracle.com,
        konrad.wilk@oracle.com, jgross@suse.com, andrew.cooper3@citrix.com
Subject: Re: [PATCH v2 7/9] sched: define TIF_ALLOW_RESCHED
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On Tue, Sep 12, 2023 at 10:26:06AM +0200 Peter Zijlstra wrote:
> On Mon, Sep 11, 2023 at 10:04:17AM -0700, Ankur Arora wrote:
> > 
> > How expensive would be always having PREEMPT_COUNT=y?
> 
> Effectively I think that is true today. At the very least Debian and
> SuSE (I can't find a RHEL .config in a hurry but I would think they too)
> ship with PREEMPT_DYNAMIC=y.
>

Yes, RHEL too.

Cheers,
Phil

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