Re: MSI interrupts

In article <vrt323$27c13$3@dont-email.me>,
Chris M. Thomasson <chris.m.thomasson.1@gmail.com> wrote:

On 3/24/2025 7:02 PM, Chris M. Thomasson 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...

>
A thread would take mtxA, then mtxB, while another would take mtxB, then
mtxA. Deadlock city is going to be visited rather soon...

Yeah, so don't do that.  :-)

I can whack myself in the head with a ballpeen hammer, too.  It
is better if I do not.

- Dan C.