On Tue, Jun 30, 2020 at 09:13:18PM +0200, Philippe Mathieu-Daudé wrote: > To be able to use multiple queues on the same hardware, > we need to have each queue able to receive IRQ notifications > in the correct AIO context. > The AIO context and the notification handler have to be proper > to each queue, not to the block driver. Move aio_context and > irq_notifier from BDRVNVMeState to NVMeQueuePair.
If I understand correctly, after this patch: 1. Each queue pair has an EventNotifier irq_notifier but only the admin queuepair's irq_notifier is hooked up to VFIO. This means all interrupts come via the admin queuepair. (This also means all queuepairs still need to be polled for completions when the interrupt fires because we don't know which queuepair had a completion event.) 2. AioContexts must be identical across all queuepairs and BlockDriverStates. Although they all have their own AioContext pointer there is no true support for different AioContexts yet. (For example, nvme_cmd_sync() is called with a bs argument but AIO_WAIT_WHILE(q->aio_context, ...) uses the queuepair aio_context so the assumption is that they match.) Please confirm and add something equivalent into the commit description so the assumptions/limitations are clear.
signature.asc
Description: PGP signature
