net/mlx5: Replace fs_node mutex with reader/writer semaphore

Currently, steering object is protected by mutex lock, replace
the mutex lock with reader/writer semaphore .
In this patch we still use only write semaphore. In downstream
patches we will switch part of the write locks to read locks.

Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c
index 41f26f4..9406e72 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c
@@ -145,10 +145,10 @@ static struct init_tree_node {
        }
 };
 
-enum fs_i_mutex_lock_class {
-       FS_MUTEX_GRANDPARENT,
-       FS_MUTEX_PARENT,
-       FS_MUTEX_CHILD
+enum fs_i_lock_class {
+       FS_LOCK_GRANDPARENT,
+       FS_LOCK_PARENT,
+       FS_LOCK_CHILD
 };
 
 static const struct rhashtable_params rhash_fte = {
@@ -184,7 +184,7 @@ static void tree_init_node(struct fs_node *node,
        atomic_set(&node->refcount, 1);
        INIT_LIST_HEAD(&node->list);
        INIT_LIST_HEAD(&node->children);
-       mutex_init(&node->lock);
+       init_rwsem(&node->lock);
        node->remove_func = remove_func;
        node->active = false;
 }
@@ -208,10 +208,10 @@ static void tree_get_node(struct fs_node *node)
 }
 
 static void nested_lock_ref_node(struct fs_node *node,
-                                enum fs_i_mutex_lock_class class)
+                                enum fs_i_lock_class class)
 {
        if (node) {
-               mutex_lock_nested(&node->lock, class);
+               down_write_nested(&node->lock, class);
                atomic_inc(&node->refcount);
        }
 }
@@ -219,7 +219,7 @@ static void nested_lock_ref_node(struct fs_node *node,
 static void lock_ref_node(struct fs_node *node)
 {
        if (node) {
-               mutex_lock(&node->lock);
+               down_write(&node->lock);
                atomic_inc(&node->refcount);
        }
 }
@@ -228,7 +228,7 @@ static void unlock_ref_node(struct fs_node *node)
 {
        if (node) {
                atomic_dec(&node->refcount);
-               mutex_unlock(&node->lock);
+               up_write(&node->lock);
        }
 }
 
@@ -1376,7 +1376,7 @@ static struct mlx5_flow_handle *add_rule_fg(struct mlx5_flow_group *fg,
                int old_action;
                int ret;
 
-               nested_lock_ref_node(&fte->node, FS_MUTEX_CHILD);
+               nested_lock_ref_node(&fte->node, FS_LOCK_CHILD);
                ret = check_conflicting_ftes(fte, flow_act);
                if (ret) {
                        handle = ERR_PTR(ret);
@@ -1400,7 +1400,7 @@ static struct mlx5_flow_handle *add_rule_fg(struct mlx5_flow_group *fg,
        fte = alloc_insert_fte(fg, match_value, flow_act);
        if (IS_ERR(fte))
                return (void *)fte;
-       nested_lock_ref_node(&fte->node, FS_MUTEX_CHILD);
+       nested_lock_ref_node(&fte->node, FS_LOCK_CHILD);
        handle = add_rule_fte(fte, fg, dest, dest_num, false);
        if (IS_ERR(handle)) {
                unlock_ref_node(&fte->node);
@@ -1548,7 +1548,7 @@ try_add_to_existing_fg(struct mlx5_flow_table *ft,
                struct fs_fte *fte;
 
                g = iter->g;
-               nested_lock_ref_node(&g->node, FS_MUTEX_PARENT);
+               nested_lock_ref_node(&g->node, FS_LOCK_PARENT);
                fte = rhashtable_lookup_fast(&g->ftes_hash, spec->match_value,
                                             rhash_fte);
                if (fte) {
@@ -1566,7 +1566,7 @@ try_add_to_existing_fg(struct mlx5_flow_table *ft,
        list_for_each_entry(iter, &match_head.list, list) {
                g = iter->g;
 
-               nested_lock_ref_node(&g->node, FS_MUTEX_PARENT);
+               nested_lock_ref_node(&g->node, FS_LOCK_PARENT);
                rule = add_rule_fg(g, spec->match_value,
                                   flow_act, dest, dest_num, NULL);
                if (!IS_ERR(rule) || PTR_ERR(rule) != -ENOSPC) {
@@ -1605,7 +1605,7 @@ _mlx5_add_flow_rules(struct mlx5_flow_table *ft,
                        return ERR_PTR(-EINVAL);
        }
 
-       nested_lock_ref_node(&ft->node, FS_MUTEX_GRANDPARENT);
+       nested_lock_ref_node(&ft->node, FS_LOCK_GRANDPARENT);
        rule = try_add_to_existing_fg(ft, spec, flow_act, dest, dest_num);
        if (!IS_ERR(rule) || PTR_ERR(rule) != -ENOENT)
                goto unlock;

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
index 6e5d25b..b5c079f 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
@@ -80,7 +80,7 @@ struct fs_node {
        struct fs_node          *parent;
        struct fs_node          *root;
        /* lock the node for writing and traversing */
-       struct mutex            lock;
+       struct rw_semaphore     lock;
        atomic_t                refcount;
        bool                    active;
        void                    (*remove_func)(struct fs_node *);