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Subject: Re: [RFC PATCH v2 00/13] Add futex2 syscall
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From:   Zebediah Figura <zfigura@codeweavers.com>
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Date:   Mon, 8 Mar 2021 10:18:29 -0600
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On 3/3/21 6:42 PM, André Almeida wrote:
>   ** The wait on multiple problem
> 
>   The use case lies in the Wine implementation of the Windows NT interface
>   WaitMultipleObjects. This Windows API function allows a thread to sleep
>   waiting on the first of a set of event sources (mutexes, timers, signal,
>   console input, etc) to signal.  Considering this is a primitive
>   synchronization operation for Windows applications, being able to quickly
>   signal events on the producer side, and quickly go to sleep on the
>   consumer side is essential for good performance of those running over Wine.

It's probably worth pointing out, for better or for worse, while this is 
*a* use case, it's also limited to an out-of-tree patch set/forked 
versions of Wine. I'm currently working on a different approach that 
should be upstreamable to Wine proper, as detailed in [1].

[1] 
https://lore.kernel.org/lkml/f4cc1a38-1441-62f8-47e4-0c67f5ad1d43@codeweavers.com/