On 2011-10-17 13:40, Michael S. Tsirkin wrote: > On Mon, Oct 17, 2011 at 11:27:57AM +0200, Jan Kiszka wrote: >> MSI config notifiers are supposed to be triggered on every relevant >> configuration change of MSI vectors or if MSI is enabled/disabled. >> >> Two notifiers are established, one for vector changes and one for general >> enabling. The former notifier additionally passes the currently active >> MSI message. >> This will allow to update potential in-kernel IRQ routes on >> changes. The latter notifier is optional and will only be used by a >> subset of clients. >> >> These notifiers are currently only available for MSI-X but will be >> extended to legacy MSI as well. >> >> Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx> > > Passing message, always, does not seem to make sense: message is only > valid if it is unmasked. If we go from unmasked to masked, the consumer could just ignore the message. > Further, IIRC the spec requires any changes to be done while > message is masked. So mask notifier makes more sense to me: > it does the same thing using one notifier that you do > using two notifiers. That's in fact a possible optimization (only invoke the callback on mask transitions). Not sure if that applies to MSI as well, probably not. To have common types, I would prefer to stay with vector config notifiers as name then. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
