IB/qib: Add DCA support
This patch adds DCA cache warming for systems that support DCA.
The code uses cpu affinity notification to react to an affinity change
from a user mode program like irqbalance and (re-)program the chip
accordingly. This notification avoids reading the current cpu on every
interrupt.
Reviewed-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
[ Add Kconfig dependency on SMP && GENERIC_HARDIRQS to avoid failure to
build due to undefined struct irq_affinity_notify. - Roland ]
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/hw/qib/Kconfig b/drivers/infiniband/hw/qib/Kconfig
index 1e603a3..d03ca4c 100644
--- a/drivers/infiniband/hw/qib/Kconfig
+++ b/drivers/infiniband/hw/qib/Kconfig
@@ -5,3 +5,11 @@
This is a low-level driver for Intel PCIe QLE InfiniBand host
channel adapters. This driver does not support the Intel
HyperTransport card (model QHT7140).
+
+config INFINIBAND_QIB_DCA
+ bool "QIB DCA support"
+ depends on INFINIBAND_QIB && DCA && SMP && GENERIC_HARDIRQS && !(INFINIBAND_QIB=y && DCA=m)
+ default y
+ ---help---
+ Setting this enables DCA support on some Intel chip sets
+ with the iba7322 HCA.