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Diffstat (limited to 'block/blk-mq-cpumap.c')
-rw-r--r--block/blk-mq-cpumap.c36
1 files changed, 36 insertions, 0 deletions
diff --git a/block/blk-mq-cpumap.c b/block/blk-mq-cpumap.c
index 9638b25fd521..444798c5374f 100644
--- a/block/blk-mq-cpumap.c
+++ b/block/blk-mq-cpumap.c
@@ -11,6 +11,7 @@
#include <linux/smp.h>
#include <linux/cpu.h>
#include <linux/group_cpus.h>
+#include <linux/device/bus.h>
#include "blk.h"
#include "blk-mq.h"
@@ -54,3 +55,38 @@ int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int index)
return NUMA_NO_NODE;
}
+
+/**
+ * blk_mq_map_hw_queues - Create CPU to hardware queue mapping
+ * @qmap: CPU to hardware queue map
+ * @dev: The device to map queues
+ * @offset: Queue offset to use for the device
+ *
+ * Create a CPU to hardware queue mapping in @qmap. The struct bus_type
+ * irq_get_affinity callback will be used to retrieve the affinity.
+ */
+void blk_mq_map_hw_queues(struct blk_mq_queue_map *qmap,
+ struct device *dev, unsigned int offset)
+
+{
+ const struct cpumask *mask;
+ unsigned int queue, cpu;
+
+ if (!dev->bus->irq_get_affinity)
+ goto fallback;
+
+ for (queue = 0; queue < qmap->nr_queues; queue++) {
+ mask = dev->bus->irq_get_affinity(dev, queue + offset);
+ if (!mask)
+ goto fallback;
+
+ for_each_cpu(cpu, mask)
+ qmap->mq_map[cpu] = qmap->queue_offset + queue;
+ }
+
+ return;
+
+fallback:
+ blk_mq_map_queues(qmap);
+}
+EXPORT_SYMBOL_GPL(blk_mq_map_hw_queues);