On Sunday, May 18, 2008 9:48 pm Hidetoshi Seto wrote: > Jesse Barnes wrote: > > Since we know MSI is a problem, let's just go with fixing that for now. > > If we find that other caps are also causing problems we can revisit > > caching all of them; the patch is simple enough. > > Humm... > I suppose it can be more simple. How about this patch? > > > everytime handle_edge_irq is called it needs to mask and unmask MSI, and > > that leads to a series of very expensive calls to pci_find_capability > > The position of MSI capability is already cached in the msi_desc when > we enter the msi_set_mask_bits(). Use it instead. > > Signed-off-by: Hidetoshi Seto <seto.hidetoshi@xxxxxxxxxxxxxx> Yeah, this looks really nice. It should also fix Arnaldo's latency problem, and really looks like a bug fix for the MSI code more than anything. Arnaldo, can you take a look & test and ack/nack? Thanks, Jesse -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
