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User-agent: mu4e 1.10.7; emacs 29.1
From: Andy Fan <zhihuifan1213@163.com>
To: Andres Freund <andres@anarazel.de>
Cc: Robert Haas <robertmhaas@gmail.com>, Matthias van de Meent
 <boekewurm+postgres@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, Thomas Munro
 <tmunro@postgresql.org>, pgsql-hackers@lists.postgresql.org
Subject: Re: the s_lock_stuck on perform_spin_delay
Date: Thu, 25 Jan 2024 15:36:41 +0800
In-reply-to: <20240123200704.icmkv2vromua2dtj@awork3.anarazel.de>
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Andres Freund <andres@anarazel.de> writes:

> On 2024-01-18 14:00:58 -0500, Robert Haas wrote:
>> > The LockBufHdr also used init_local_spin_delay / perform_spin_delay
>> > infrastruce and then it has the same issue like ${subject}, it is pretty
>> > like the code in s_lock; Based on my current knowledge, I think we
>> > should add the check there.
>> 
>> I'd like to hear from Andres, if possible. @Andres: Should these
>> sanity checks apply only to spin locks per se, or also to buffer
>> header locks?
>
> They also should apply to buffer header locks. The exact same dangers apply
> there. The only reason this isn't using a plain spinlock is that this way we
> can modify more state with a single atomic operation. But all the dangers of
> using spinlocks apply just as well.

Thanks for speaking on this! 

-- 
Best Regards
Andy Fan