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0 pointseptcyka1y ago0 comments

The assumption made by rust is that a future is cancelled when it is dropped.

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eqvinox1y ago· 1 in thread

Ah, Thanks, that makes sense, but then I don't understand how this isn't just a bug in these Rust runtimes. As in: the drop codepath on the future needs to not only submit the cancellation SQE into io_uring, it also needs to still process CQEs from the original request that pop up before the CQE for the cancellation…

NB: I have only done a little bit of Rust, but am hoping to move there in the future — but I am working on C code interfacing io_uring… I will say doing this correctly does in fact require a bit of brainpower when writing that code.

eptcykaOP1y ago

I am not well versed in the async things as of late, but one complication is that the drop implementation is a blocking one. This could easily lead to deadlocks. Or the drop implementation could spawn an async task to clean up after itself later.

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