Re: [PATCH v9] linux: Do not spawn a new thread for SIGEV_THREAD (BZ 30558, 27895, 29705, 32833)

On 7/10/26 10:24 AM, Florian Weimer wrote:
> * Adhemerval Zanella:
> 
>> The current timer_create SIGEV_THREAD implementation has some
>> downsides:
>>
>>    1. There is no way to report failure at thread creation when a
>>       timer triggers.  It means that it might occur unreported and with
>>       missed events depending of the system load.
> 
> Error reporting can be added to the existing implementation, by
> incrementing a counter on pthread_create failure and returning the sum
> of this counter and the kernel counter in timer_getoverrun, I believe.

You could also fall back to the 1 thread you created via timer_create to
make serial progress in the worst case.

This is the suggestion that Rich makes in comment 28:
https://sourceware.org/bugzilla/show_bug.cgi?id=30558#c28

> I think changing from multiple threads to a single serialized thread is
> quite drastic and may not be what applications expect.  We might need
> another round of compatibility symbols for that.
That's a good point I hadn't considered, but I did comment on it in my
v9 review.

-- 
Cheers,
Carlos.