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, 76 insertions, 31 deletions

diff --git a/drivers/infiniband/hw/qib/qib_iba7322.c b/drivers/infiniband/hw/qib/qib_iba7322.c
index 41e92089e41..060b9606446 100644
--- a/drivers/infiniband/hw/qib/qib_iba7322.c
+++ b/drivers/infiniband/hw/qib/qib_iba7322.c
@@ -541,8 +541,7 @@ struct qib_chip_specific {
 	u32 lastbuf_for_pio;
 	u32 stay_in_freeze;
 	u32 recovery_ports_initted;
-	struct msix_entry *msix_entries;
-	void  **msix_arg;
+	struct qib_msix_entry *msix_entries;
 	unsigned long *sendchkenable;
 	unsigned long *sendgrhchk;
 	unsigned long *sendibchk;
@@ -639,24 +638,24 @@ static struct {
 	int lsb;
 	int port; /* 0 if not port-specific, else port # */
 } irq_table[] = {
-	{ QIB_DRV_NAME, qib_7322intr, -1, 0 },
-	{ QIB_DRV_NAME " (buf avail)", qib_7322bufavail,
+	{ "", qib_7322intr, -1, 0 },
+	{ " (buf avail)", qib_7322bufavail,
 		SYM_LSB(IntStatus, SendBufAvail), 0 },
-	{ QIB_DRV_NAME " (sdma 0)", sdma_intr,
+	{ " (sdma 0)", sdma_intr,
 		SYM_LSB(IntStatus, SDmaInt_0), 1 },
-	{ QIB_DRV_NAME " (sdma 1)", sdma_intr,
+	{ " (sdma 1)", sdma_intr,
 		SYM_LSB(IntStatus, SDmaInt_1), 2 },
-	{ QIB_DRV_NAME " (sdmaI 0)", sdma_idle_intr,
+	{ " (sdmaI 0)", sdma_idle_intr,
 		SYM_LSB(IntStatus, SDmaIdleInt_0), 1 },
-	{ QIB_DRV_NAME " (sdmaI 1)", sdma_idle_intr,
+	{ " (sdmaI 1)", sdma_idle_intr,
 		SYM_LSB(IntStatus, SDmaIdleInt_1), 2 },
-	{ QIB_DRV_NAME " (sdmaP 0)", sdma_progress_intr,
+	{ " (sdmaP 0)", sdma_progress_intr,
 		SYM_LSB(IntStatus, SDmaProgressInt_0), 1 },
-	{ QIB_DRV_NAME " (sdmaP 1)", sdma_progress_intr,
+	{ " (sdmaP 1)", sdma_progress_intr,
 		SYM_LSB(IntStatus, SDmaProgressInt_1), 2 },
-	{ QIB_DRV_NAME " (sdmaC 0)", sdma_cleanup_intr,
+	{ " (sdmaC 0)", sdma_cleanup_intr,
 		SYM_LSB(IntStatus, SDmaCleanupDone_0), 1 },
-	{ QIB_DRV_NAME " (sdmaC 1)", sdma_cleanup_intr,
+	{ " (sdmaC 1)", sdma_cleanup_intr,
 		SYM_LSB(IntStatus, SDmaCleanupDone_1), 2 },
 };
 
@@ -2567,9 +2566,13 @@ static void qib_7322_nomsix(struct qib_devdata *dd)
 		int i;
 
 		dd->cspec->num_msix_entries = 0;
-		for (i = 0; i < n; i++)
-			free_irq(dd->cspec->msix_entries[i].vector,
-				 dd->cspec->msix_arg[i]);
+		for (i = 0; i < n; i++) {
+			irq_set_affinity_hint(
+			  dd->cspec->msix_entries[i].msix.vector, NULL);
+			free_cpumask_var(dd->cspec->msix_entries[i].mask);
+			free_irq(dd->cspec->msix_entries[i].msix.vector,
+			   dd->cspec->msix_entries[i].arg);
+		}
 		qib_nomsix(dd);
 	}
 	/* make sure no MSIx interrupts are left pending */
@@ -2597,7 +2600,6 @@ static void qib_setup_7322_cleanup(struct qib_devdata *dd)
 	kfree(dd->cspec->sendgrhchk);
 	kfree(dd->cspec->sendibchk);
 	kfree(dd->cspec->msix_entries);
-	kfree(dd->cspec->msix_arg);
 	for (i = 0; i < dd->num_pports; i++) {
 		unsigned long flags;
 		u32 mask = QSFP_GPIO_MOD_PRS_N |
@@ -3070,6 +3072,8 @@ static void qib_setup_7322_interrupt(struct qib_devdata *dd, int clearpend)
 	int ret, i, msixnum;
 	u64 redirect[6];
 	u64 mask;
+	const struct cpumask *local_mask;
+	int firstcpu, secondcpu = 0, currrcvcpu = 0;
 
 	if (!dd->num_pports)
 		return;
@@ -3118,13 +3122,28 @@ try_intx:
 	memset(redirect, 0, sizeof redirect);
 	mask = ~0ULL;
 	msixnum = 0;
+	local_mask = cpumask_of_pcibus(dd->pcidev->bus);
+	firstcpu = cpumask_first(local_mask);
+	if (firstcpu >= nr_cpu_ids ||
+			cpumask_weight(local_mask) == num_online_cpus()) {
+		local_mask = topology_core_cpumask(0);
+		firstcpu = cpumask_first(local_mask);
+	}
+	if (firstcpu < nr_cpu_ids) {
+		secondcpu = cpumask_next(firstcpu, local_mask);
+		if (secondcpu >= nr_cpu_ids)
+			secondcpu = firstcpu;
+		currrcvcpu = secondcpu;
+	}
 	for (i = 0; msixnum < dd->cspec->num_msix_entries; i++) {
 		irq_handler_t handler;
-		const char *name;
 		void *arg;
 		u64 val;
 		int lsb, reg, sh;
 
+		dd->cspec->msix_entries[msixnum].
+			name[sizeof(dd->cspec->msix_entries[msixnum].name) - 1]
+			= '\0';
 		if (i < ARRAY_SIZE(irq_table)) {
 			if (irq_table[i].port) {
 				/* skip if for a non-configured port */
@@ -3135,7 +3154,11 @@ try_intx:
 				arg = dd;
 			lsb = irq_table[i].lsb;
 			handler = irq_table[i].handler;
-			name = irq_table[i].name;
+			snprintf(dd->cspec->msix_entries[msixnum].name,
+				sizeof(dd->cspec->msix_entries[msixnum].name)
+				 - 1,
+				QIB_DRV_NAME "%d%s", dd->unit,
+				irq_table[i].name);
 		} else {
 			unsigned ctxt;
 
@@ -3148,23 +3171,28 @@ try_intx:
 				continue;
 			lsb = QIB_I_RCVAVAIL_LSB + ctxt;
 			handler = qib_7322pintr;
-			name = QIB_DRV_NAME " (kctx)";
+			snprintf(dd->cspec->msix_entries[msixnum].name,
+				sizeof(dd->cspec->msix_entries[msixnum].name)
+				 - 1,
+				QIB_DRV_NAME "%d (kctx)", dd->unit);
 		}
-		ret = request_irq(dd->cspec->msix_entries[msixnum].vector,
-				  handler, 0, name, arg);
+		ret = request_irq(
+			dd->cspec->msix_entries[msixnum].msix.vector,
+			handler, 0, dd->cspec->msix_entries[msixnum].name,
+			arg);
 		if (ret) {
 			/*
 			 * Shouldn't happen since the enable said we could
 			 * have as many as we are trying to setup here.
 			 */
 			qib_dev_err(dd, "Couldn't setup MSIx "
-				    "interrupt (vec=%d, irq=%d): %d\n", msixnum,
-				    dd->cspec->msix_entries[msixnum].vector,
-				    ret);
+				"interrupt (vec=%d, irq=%d): %d\n", msixnum,
+				dd->cspec->msix_entries[msixnum].msix.vector,
+				ret);
 			qib_7322_nomsix(dd);
 			goto try_intx;
 		}
-		dd->cspec->msix_arg[msixnum] = arg;
+		dd->cspec->msix_entries[msixnum].arg = arg;
 		if (lsb >= 0) {
 			reg = lsb / IBA7322_REDIRECT_VEC_PER_REG;
 			sh = (lsb % IBA7322_REDIRECT_VEC_PER_REG) *
@@ -3174,6 +3202,25 @@ try_intx:
 		}
 		val = qib_read_kreg64(dd, 2 * msixnum + 1 +
 			(QIB_7322_MsixTable_OFFS / sizeof(u64)));
+		if (firstcpu < nr_cpu_ids &&
+			zalloc_cpumask_var(
+				&dd->cspec->msix_entries[msixnum].mask,
+				GFP_KERNEL)) {
+			if (handler == qib_7322pintr) {
+				cpumask_set_cpu(currrcvcpu,
+					dd->cspec->msix_entries[msixnum].mask);
+				currrcvcpu = cpumask_next(currrcvcpu,
+					local_mask);
+				if (currrcvcpu >= nr_cpu_ids)
+					currrcvcpu = secondcpu;
+			} else {
+				cpumask_set_cpu(firstcpu,
+					dd->cspec->msix_entries[msixnum].mask);
+			}
+			irq_set_affinity_hint(
+				dd->cspec->msix_entries[msixnum].msix.vector,
+				dd->cspec->msix_entries[msixnum].mask);
+		}
 		msixnum++;
 	}
 	/* Initialize the vector mapping */
@@ -3365,7 +3412,7 @@ static int qib_do_7322_reset(struct qib_devdata *dd)
 	if (msix_entries) {
 		/* restore the MSIx vector address and data if saved above */
 		for (i = 0; i < msix_entries; i++) {
-			dd->cspec->msix_entries[i].entry = i;
+			dd->cspec->msix_entries[i].msix.entry = i;
 			if (!msix_vecsave || !msix_vecsave[2 * i])
 				continue;
 			qib_write_kreg(dd, 2 * i +
@@ -6865,15 +6912,13 @@ struct qib_devdata *qib_init_iba7322_funcs(struct pci_dev *pdev,
 
 	tabsize = actual_cnt;
 	dd->cspec->msix_entries = kmalloc(tabsize *
-			sizeof(struct msix_entry), GFP_KERNEL);
-	dd->cspec->msix_arg = kmalloc(tabsize *
-			sizeof(void *), GFP_KERNEL);
-	if (!dd->cspec->msix_entries || !dd->cspec->msix_arg) {
+			sizeof(struct qib_msix_entry), GFP_KERNEL);
+	if (!dd->cspec->msix_entries) {
 		qib_dev_err(dd, "No memory for MSIx table\n");
 		tabsize = 0;
 	}
 	for (i = 0; i < tabsize; i++)
-		dd->cspec->msix_entries[i].entry = i;
+		dd->cspec->msix_entries[i].msix.entry = i;
 
 	if (qib_pcie_params(dd, 8, &tabsize, dd->cspec->msix_entries))
 		qib_dev_err(dd, "Failed to setup PCIe or interrupts; "