Re: [PATCH] Add support for multiple MSI on x86

[Clemens Ladisch]

Roland Dreier wrote:
> > Yes, but there are MSI devices in the field...
> 
> But do any of them benefit from having multiple interrupt vectors available?
> 
> If I recall correct, willy was motivated by AHCI performance to try this out,
> and in the end things didn't go any faster using multiple MSI.
> 
> The big win with multiple interrupt vectors is when you have independent
> queues that you can point different CPUs at, and give each CPU its own
> interrupt.

And this is how AHCI is designed, but libahci.c currently wraps its
interrupt handler in a device-wide lock.  I don't know if that test also
reorganized the driver code.


Regards,
Clemens
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