at 11:34 PM, Keith Busch wrote:
> On Fri, Aug 26, 2022 at 11:12:04PM +0800, Jinhao Fan wrote:
>> Use KVM's irqfd to send interrupts when possible. This approach is
>> thread safe. Moreover, it does not have the inter-thread communication
>> overhead of plain event notifiers since handler callback
Use KVM's irqfd to send interrupts when possible. This approach is
thread safe. Moreover, it does not have the inter-thread communication
overhead of plain event notifiers since handler callback are called
in the same system call as irqfd write.
Signed-off-by: Jinhao Fan
Signed-off-by: Klaus Jens
Add an option "iothread=x" to do emulation in a seperate iothread.
This improves the performance because QEMU's main loop is responsible
for a lot of other work while iothread is dedicated to NVMe emulation.
Moreover, emulating in iothread brings the potential of polling on
SQ/CQ doorbells, which I
When the new option 'irq-eventfd' is turned on, the IO emulation code
signals an eventfd when it want to (de)assert an irq. The main loop
eventfd handler does the actual irq (de)assertion. This paves the way
for iothread support since QEMU's interrupt emulation is not thread
safe.
Asserting and d
Add AioContext polling handlers for NVMe SQ and CQ. By employing polling,
the latency of NVMe IO emulation is greatly reduced. The SQ polling
handler checks for updates on the SQ tail shadow doorbell buffer. The CQ
polling handler is an empty function because we procatively polls the CQ
head shadow
