IB/qib: Add logic for affinity hint

Call irq_set_affinity_hint() to give userspace programs such as
irqbalance the information to be able to distribute qib interrupts
appropriately.

The logic allocates all non-receive interrupts to the first CPU local
to the HCA.  Receive interrupts are allocated round robin starting
with the second CPU local to the HCA with potential wrap back to the
second CPU.

This patch also adds a refinement to the name registered for MSI-X
interrupts so that user level scripts can determine the device
associated with the IRQs when there are multiple HCAs with a
potentially different set of local CPUs.

Signed-off-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 19 insertions, 2 deletions

diff --git a/drivers/infiniband/hw/qib/qib_pcie.c b/drivers/infiniband/hw/qib/qib_pcie.c
index 0fde788e1100..790646ef5106 100644
--- a/drivers/infiniband/hw/qib/qib_pcie.c
+++ b/drivers/infiniband/hw/qib/qib_pcie.c
@@ -194,11 +194,24 @@ void qib_pcie_ddcleanup(struct qib_devdata *dd)
 }
 
 static void qib_msix_setup(struct qib_devdata *dd, int pos, u32 *msixcnt,
-			   struct msix_entry *msix_entry)
+			   struct qib_msix_entry *qib_msix_entry)
 {
 	int ret;
 	u32 tabsize = 0;
 	u16 msix_flags;
+	struct msix_entry *msix_entry;
+	int i;
+
+	/* We can't pass qib_msix_entry array to qib_msix_setup
+	 * so use a dummy msix_entry array and copy the allocated
+	 * irq back to the qib_msix_entry array. */
+	msix_entry = kmalloc(*msixcnt * sizeof(*msix_entry), GFP_KERNEL);
+	if (!msix_entry) {
+		ret = -ENOMEM;
+		goto do_intx;
+	}
+	for (i = 0; i < *msixcnt; i++)
+		msix_entry[i] = qib_msix_entry[i].msix;
 
 	pci_read_config_word(dd->pcidev, pos + PCI_MSIX_FLAGS, &msix_flags);
 	tabsize = 1 + (msix_flags & PCI_MSIX_FLAGS_QSIZE);
@@ -209,11 +222,15 @@ static void qib_msix_setup(struct qib_devdata *dd, int pos, u32 *msixcnt,
 		tabsize = ret;
 		ret = pci_enable_msix(dd->pcidev, msix_entry, tabsize);
 	}
+do_intx:
 	if (ret) {
 		qib_dev_err(dd, "pci_enable_msix %d vectors failed: %d, "
 			    "falling back to INTx\n", tabsize, ret);
 		tabsize = 0;
 	}
+	for (i = 0; i < tabsize; i++)
+		qib_msix_entry[i].msix = msix_entry[i];
+	kfree(msix_entry);
 	*msixcnt = tabsize;
 
 	if (ret)
@@ -251,7 +268,7 @@ static int qib_msi_setup(struct qib_devdata *dd, int pos)
 }
 
 int qib_pcie_params(struct qib_devdata *dd, u32 minw, u32 *nent,
-		    struct msix_entry *entry)
+		    struct qib_msix_entry *entry)
 {
 	u16 linkstat, speed;
 	int pos = 0, pose, ret = 1;