[PATCH 2/7] genirq/affinity: Handle pre/post vectors in irq_calc_affinity_vectors()

[Christoph Hellwig]

From: Christogh Hellwig <h...@lst.de>

Only calculate the affinity for the main I/O vectors, and skip the
pre or post vectors specified by struct irq_affinity.

Also remove the irq_affinity cpumask argument that has never been used.
If we ever need it in the future we can pass it through struct
irq_affinity.

Signed-off-by: Christogh Hellwig <h...@lst.de>
---
 drivers/pci/msi.c         |  6 ++----
 include/linux/interrupt.h |  4 ++--
 kernel/irq/affinity.c     | 24 ++++++++++--------------
 3 files changed, 14 insertions(+), 20 deletions(-)

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index ad70507..c58d3c2 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -1091,8 +1091,7 @@ static int __pci_enable_msi_range(struct pci_dev *dev, 
int minvec, int maxvec,
 
        for (;;) {
                if (affinity) {
-                       nvec = irq_calc_affinity_vectors(dev->irq_affinity,
-                                       nvec);
+                       nvec = irq_calc_affinity_vectors(nvec, NULL);
                        if (nvec < minvec)
                                return -ENOSPC;
                }
@@ -1140,8 +1139,7 @@ static int __pci_enable_msix_range(struct pci_dev *dev,
 
        for (;;) {
                if (affinity) {
-                       nvec = irq_calc_affinity_vectors(dev->irq_affinity,
-                                       nvec);
+                       nvec = irq_calc_affinity_vectors(nvec, NULL);
                        if (nvec < minvec)
                                return -ENOSPC;
                }
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 7284bcd..092adfb 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -291,7 +291,7 @@ extern int
 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify 
*notify);
 
 struct cpumask *irq_create_affinity_masks(const struct cpumask *affinity, int 
nvec);
-int irq_calc_affinity_vectors(const struct cpumask *affinity, int maxvec);
+int irq_calc_affinity_vectors(int maxvec, const struct irq_affinity *affd);
 
 #else /* CONFIG_SMP */
 
@@ -331,7 +331,7 @@ irq_create_affinity_masks(const struct cpumask *affinity, 
int nvec)
 }
 
 static inline int
-irq_calc_affinity_vectors(const struct cpumask *affinity, int maxvec)
+irq_calc_affinity_vectors(int maxvec, const struct irq_affinity *affd)
 {
        return maxvec;
 }
diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c
index 17f51d63..8d92597 100644
--- a/kernel/irq/affinity.c
+++ b/kernel/irq/affinity.c
@@ -131,24 +131,20 @@ struct cpumask *irq_create_affinity_masks(const struct 
cpumask *affinity,
 }
 
 /**
- * irq_calc_affinity_vectors - Calculate to optimal number of vectors for a 
given affinity mask
- * @affinity:          The affinity mask to spread. If NULL cpu_online_mask
- *                     is used
- * @maxvec:            The maximum number of vectors available
+ * irq_calc_affinity_vectors - Calculate the optimal number of vectors
+ * @maxvec:    The maximum number of vectors available
+ * @affd:      Description of the affinity requirements
  */
-int irq_calc_affinity_vectors(const struct cpumask *affinity, int maxvec)
+int irq_calc_affinity_vectors(int maxvec, const struct irq_affinity *affd)
 {
-       int cpus, ret;
+       int resv = affd->pre_vectors + affd->post_vectors;
+       int vecs = maxvec - resv;
+       int cpus;
 
        /* Stabilize the cpumasks */
        get_online_cpus();
-       /* If the supplied affinity mask is NULL, use cpu online mask */
-       if (!affinity)
-               affinity = cpu_online_mask;
-
-       cpus = cpumask_weight(affinity);
-       ret = (cpus < maxvec) ? cpus : maxvec;
-
+       cpus = cpumask_weight(cpu_online_mask);
        put_online_cpus();
-       return ret;
+
+       return min(cpus, vecs) + resv;
 }
-- 
2.1.4