usleep() is obsolete and context objects

[ghenry]

HI @aberaud

Just bringing in the new changes in your example into my code and note:

opendht/tools/dhtcnode.c

Line 248 in 0302cee

usleep(10000);

https://man7.org/linux/man-pages/man3/usleep.3.html#CONFORMING_TO

4.3BSD, POSIX.1-2001. POSIX.1-2001 declares this function
obsolete; use nanosleep(2) instead. POSIX.1-2008 removes the
specification of usleep().

so this fails to compile in my code.

Also, what's the benefit of bringing atomic_XXX? We also now have two set of ctx objects to manage.

Thanks.

[aberaud]

The atomic boolean is simply used to pool-block for the shutdown callback (which is called from another thread).

The "optimal" way (with no pooling) would be to use a condition variable, but that was a bit overkill for that simple case.

If the bool was not atomic, it would be a data race, and it would in theory be possible (and valid, but unlikely in practice) for the main thread to keep using the CPU-core-cached value 'false' instead of the value 'true' stored by the shutdown callback.

Having many context objects is not a problem: these objects track the state of async operations like listen, get, or shutdown.
There should be one instance per operation performed, unless the user is not interested to know how the async op is doing.

[ghenry]

Thanks. Makes sense. Just usleep to migrate later.

…

On Wed, 27 Apr 2022 at 23:29, Adrien Béraud ***@***.***> wrote: The atomic boolean is simply used to pool-block for the shutdown callback (which is called from another thread). The "optimal" way (with no pooling) would be to use a condition variable, but that was a bit overkill for that simple case. If the bool was not atomic, it would be a data race, and it would in theory be possible (and valid, but unlikely in practice) for the main thread to keep using the CPU-core-cached value 'false' instead of the value 'true' stored by the shutdown callback. Having many context objects is not a problem: these objects track the state of async operations like listen, get, or shutdown. There should be one instance per operation performed, unless the user is not interested to know how the async op is doing. — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

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