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From: "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups: comp.arch
Subject: Re: MSI interrupts
Date: Tue, 25 Mar 2025 13:32:36 -0700
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In-Reply-To: <vru36r$ja1$1@reader1.panix.com>

On 3/25/2025 4:14 AM, Dan Cross wrote:
> In article <vrt2sb$27c13$2@dont-email.me>,
> Chris M. Thomasson <chris.m.thomasson.1@gmail.com> wrote:
>> On 3/24/2025 1:14 PM, Dan Cross wrote:
>>> In article <vrsaro$1faj3$9@dont-email.me>,
>>> Chris M. Thomasson <chris.m.thomasson.1@gmail.com> wrote:
>>>> On 3/24/2025 11:49 AM, Dan Cross wrote:
>>>>> [snip]
>>>>> I'm sure one could do a lockless pop using a cmp exchange, but I
>>>>> wanted to a scenario where one would want to hold onto both
>>>>> locks throughout the critical section for some reason.
>>>>> I just don't see how this works in the proposed scenario.
>>>>
>>>> You want to hold lock A while lock B us being used? That can be tricky.
>>>
>>> Really?  This happens all the time.  Of course it can be tricky,
>>> as concurrent programming always is, but it's incredibly normal.
>>
>> Locking order comes into play here. Uggg... I have seen nightmare code
>> that was using recursion as well... It deadlocked at a certain depth,
>> only under the right conditions. The locking order was not properly
>> respected...
> 
> Well, of course it does.  But it's still something that people
> do all the time.

Indeed. :^) I have had to debug nightmare code from "other" people... 
What a bitch!