Am Montag, den 27.10.2014, 20:16 +0100 schrieb Heiner Kallweit: > Thanks, Lucas. > > It's interesting however that the igb driver claims it's using MSI-X. > Maybe the DW PCIE drivers offers MSI-X on the bus and just internally falls back to MSI? > Are you running a upstream or downstream vendor kernel? On my upstream kernel igb properly falls back to MSI. Regards, Lucas > Rgds, Heiner > > [ 4.165850] igb: Intel(R) Gigabit Ethernet Network Driver - version 5.2.15-k > [ 4.172930] igb: Copyright (c) 2007-2014 Intel Corporation. > [ 4.178638] igb 0000:01:00.0: enabling device (0140 -> 0142) > [ 4.235789] igb 0000:01:00.0: added PHC on eth0 > [ 4.235793] igb 0000:01:00.0: Intel(R) Gigabit Ethernet Network Connection > [ 4.235799] igb 0000:01:00.0: eth0: (PCIe:2.5Gb/s:Width x1) 00:01:c0:14:b1:58 > [ 4.235804] igb 0000:01:00.0: eth0: PBA No: FFFFFF-0FF > [ 4.235810] igb 0000:01:00.0: Using MSI-X interrupts. 2 rx queue(s), 2 tx queue(s) > > > Am 27.10.2014 um 09:52 schrieb Lucas Stach: > > Hello Heiner, > > > > Am Sonntag, den 26.10.2014, 19:05 +0100 schrieb Heiner Kallweit: > >> I use a mini pc with i.mx6 dual and Intel igb based nic (I211) connected via PCIE. > >> igb driver uses MSI-X and creates two rx/tx queue pairs. However the IRQs of all queues are handled by the same CPU. > >> Changing affinity is not possible. Obvious direct reason is that irq_chip PCI-MSI doesn't implement the callback > >> for setting cpu affinity. > >> I'd appreciate a hint whether this is a general limitation of the Cortex-A9 / GICv1 / Synopsys Designware > >> architecture or whether just a proper implementation is missing yet. > >> > >> Rgds, Heiner > > > > The MSI controller on imx6 doesn't support MSI-X so igb falls back to > > regular MSI interrupts. Also all MSI interrupts are aggregated into a > > single GIC interrupt line. This means the best we could do is switch all > > PCIe MSI interrupts to some other CPU. Configuring the CPU affinity on a > > per interrupt basis is impossible on this hardware. > > > > Regards, > > Lucas > > > > -- > 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 -- Pengutronix e.K. | Lucas Stach | Industrial Linux Solutions | http://www.pengutronix.de/ | -- 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
