tech-kern archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: RFC: MSI/MSI-X implementation

On Thu, Nov 13, 2014 at 12:41:38PM +0900, Kengo NAKAHARA wrote:
> (2014/11/13 11:54), David Young wrote:
> >On Fri, Nov 07, 2014 at 04:41:55PM +0900, Kengo NAKAHARA wrote:
> >>Could you comment the specification and implementation?
> >
> >The user should not be on the hook to set processor affinity for the
> >interrupts.  That is more properly the responsibility of the designer
> >and OS.
> I wrote unclear explanation..., so please let me redescribe.
> This MSI/MSI-X API *design* is independent from processor affinity.
> The device dirvers can use MSI/MSI-X and processor affinity
> independently of each other. In other words, legacy interrupts and
> INTx interrupts can use processor affinity still. Furthermore,
> MSI/MSI-X may or may not use processor affinity.

MSI/MSI-X is not half as useful as it ought to be if a driver's author
cannot spread interrupt workload across the available CPUs.  If you
don't mind, please share your processor affinity proposal and show how
it works with interrupts.


David Young    Urbana, IL    (217) 721-9981

Home | Main Index | Thread Index | Old Index