6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: John Meneghini <jmeneghi@xxxxxxxxxx>
[ Upstream commit 3d7c2fd2ea704812867f9586270a2516377482a3 ]
This patch prepares for the introduction of a new iopolicy by breaking up
the nvme_find_path() code path into sub-routines.
Signed-off-by: John Meneghini <jmeneghi@xxxxxxxxxx>
Reviewed-by: Sagi Grimberg <sagi@xxxxxxxxxxx>
Reviewed-by: Chaitanya Kulkarni <kch@xxxxxxxxxx>
Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
Stable-dep-of: 5dd18f09ce73 ("nvme/multipath: Fix RCU list traversal to use SRCU primitive")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/nvme/host/multipath.c | 21 +++++++++++++++------
1 file changed, 15 insertions(+), 6 deletions(-)
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index ede2a14dad8be..53eee6fc68392 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -290,10 +290,15 @@ static struct nvme_ns *nvme_next_ns(struct nvme_ns_head *head,
return list_first_or_null_rcu(&head->list, struct nvme_ns, siblings);
}
-static struct nvme_ns *nvme_round_robin_path(struct nvme_ns_head *head,
- int node, struct nvme_ns *old)
+static struct nvme_ns *nvme_round_robin_path(struct nvme_ns_head *head)
{
struct nvme_ns *ns, *found = NULL;
+ int node = numa_node_id();
+ struct nvme_ns *old = srcu_dereference(head->current_path[node],
+ &head->srcu);
+
+ if (unlikely(!old))
+ return __nvme_find_path(head, node);
if (list_is_singular(&head->list)) {
if (nvme_path_is_disabled(old))
@@ -339,7 +344,7 @@ static inline bool nvme_path_is_optimized(struct nvme_ns *ns)
ns->ana_state == NVME_ANA_OPTIMIZED;
}
-inline struct nvme_ns *nvme_find_path(struct nvme_ns_head *head)
+static struct nvme_ns *nvme_numa_path(struct nvme_ns_head *head)
{
int node = numa_node_id();
struct nvme_ns *ns;
@@ -347,14 +352,18 @@ inline struct nvme_ns *nvme_find_path(struct nvme_ns_head *head)
ns = srcu_dereference(head->current_path[node], &head->srcu);
if (unlikely(!ns))
return __nvme_find_path(head, node);
-
- if (READ_ONCE(head->subsys->iopolicy) == NVME_IOPOLICY_RR)
- return nvme_round_robin_path(head, node, ns);
if (unlikely(!nvme_path_is_optimized(ns)))
return __nvme_find_path(head, node);
return ns;
}
+inline struct nvme_ns *nvme_find_path(struct nvme_ns_head *head)
+{
+ if (READ_ONCE(head->subsys->iopolicy) == NVME_IOPOLICY_RR)
+ return nvme_round_robin_path(head);
+ return nvme_numa_path(head);
+}
+
static bool nvme_available_path(struct nvme_ns_head *head)
{
struct nvme_ns *ns;
--
2.43.0
