summaryrefslogtreecommitdiffstats
path: root/block/blk-mq-rdma.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /block/blk-mq-rdma.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'block/blk-mq-rdma.c')
-rw-r--r--block/blk-mq-rdma.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/block/blk-mq-rdma.c b/block/blk-mq-rdma.c
new file mode 100644
index 000000000..29c1f4d6e
--- /dev/null
+++ b/block/blk-mq-rdma.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2017 Sagi Grimberg.
+ */
+#include <linux/blk-mq.h>
+#include <linux/blk-mq-rdma.h>
+#include <rdma/ib_verbs.h>
+
+/**
+ * blk_mq_rdma_map_queues - provide a default queue mapping for rdma device
+ * @map: CPU to hardware queue map.
+ * @dev: rdma device to provide a mapping for.
+ * @first_vec: first interrupt vectors to use for queues (usually 0)
+ *
+ * This function assumes the rdma device @dev has at least as many available
+ * interrupt vetors as @set has queues. It will then query it's affinity mask
+ * and built queue mapping that maps a queue to the CPUs that have irq affinity
+ * for the corresponding vector.
+ *
+ * In case either the driver passed a @dev with less vectors than
+ * @set->nr_hw_queues, or @dev does not provide an affinity mask for a
+ * vector, we fallback to the naive mapping.
+ */
+void blk_mq_rdma_map_queues(struct blk_mq_queue_map *map,
+ struct ib_device *dev, int first_vec)
+{
+ const struct cpumask *mask;
+ unsigned int queue, cpu;
+
+ for (queue = 0; queue < map->nr_queues; queue++) {
+ mask = ib_get_vector_affinity(dev, first_vec + queue);
+ if (!mask)
+ goto fallback;
+
+ for_each_cpu(cpu, mask)
+ map->mq_map[cpu] = map->queue_offset + queue;
+ }
+
+ return;
+
+fallback:
+ blk_mq_map_queues(map);
+}
+EXPORT_SYMBOL_GPL(blk_mq_rdma_map_queues);