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Date: Tue, 11 Feb 2025 15:50:16 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: I Hsin Cheng <richard120310@gmail.com>
Cc: zhengqi.arch@bytedance.com, linux-mm@kvack.org,
 linux-kernel@vger.kernel.org, jserv@ccns.ncku.edu.tw
Subject: Re: [PATCH] mm: pgtable: Unlock pml without branches when
 !start_pte
Message-Id: <20250211155016.857387cd35e19a463d779cae@linux-foundation.org>
In-Reply-To: <Z6rzC5MGG8xrjnnF@vaxr-BM6660-BM6360>
References: <20250210100948.312130-1-richard120310@gmail.com>
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On Tue, 11 Feb 2025 14:49:47 +0800 I Hsin Cheng <richard120310@gmail.com> wrote:

> >       if (ptl != pml)
> > +out_unlock:
> >               spin_unlock(pml);
> >  }
> > _
> >
> > but that's really ugly.
> 
> I agree. Would you be so nice to suggest some test method for me so I
> can try to test how much benefit we can get from this?
> 
> If the case happens frequently enough I think it might be worth it?

I expect this error patch is basically never taken - put a printk in
there and run some tests?