RDMA/core: Define client_data_lock as rwlock instead of spinlock

Even though device registration/unregistration and client
registration/unregistration is not a performance path, define the
client_data_lock as rwlock for code clarity.

Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index a51d16a..a093914 100644 (file)
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -270,7 +270,7 @@ struct ib_device *ib_alloc_device(size_t size)
 
        INIT_LIST_HEAD(&device->event_handler_list);
        spin_lock_init(&device->event_handler_lock);
-       spin_lock_init(&device->client_data_lock);
+       rwlock_init(&device->client_data_lock);
        INIT_LIST_HEAD(&device->client_data_list);
        INIT_LIST_HEAD(&device->port_list);
 
@@ -307,9 +307,9 @@ static int add_client_context(struct ib_device *device, struct ib_client *client
        context->going_down = false;
 
        down_write(&lists_rwsem);
-       spin_lock_irq(&device->client_data_lock);
+       write_lock_irq(&device->client_data_lock);
        list_add(&context->list, &device->client_data_list);
-       spin_unlock_irq(&device->client_data_lock);
+       write_unlock_irq(&device->client_data_lock);
        up_write(&lists_rwsem);
 
        return 0;
@@ -586,10 +586,10 @@ void ib_unregister_device(struct ib_device *device)
 
        down_write(&lists_rwsem);
        list_del(&device->core_list);
-       spin_lock_irq(&device->client_data_lock);
+       write_lock_irq(&device->client_data_lock);
        list_for_each_entry(context, &device->client_data_list, list)
                context->going_down = true;
-       spin_unlock_irq(&device->client_data_lock);
+       write_unlock_irq(&device->client_data_lock);
        downgrade_write(&lists_rwsem);
 
        list_for_each_entry(context, &device->client_data_list, list) {
@@ -609,13 +609,13 @@ void ib_unregister_device(struct ib_device *device)
        kfree(device->port_pkey_list);
 
        down_write(&lists_rwsem);
-       spin_lock_irqsave(&device->client_data_lock, flags);
+       write_lock_irqsave(&device->client_data_lock, flags);
        list_for_each_entry_safe(context, tmp, &device->client_data_list,
                                 list) {
                list_del(&context->list);
                kfree(context);
        }
-       spin_unlock_irqrestore(&device->client_data_lock, flags);
+       write_unlock_irqrestore(&device->client_data_lock, flags);
        up_write(&lists_rwsem);
 
        device->reg_state = IB_DEV_UNREGISTERED;
@@ -678,14 +678,14 @@ void ib_unregister_client(struct ib_client *client)
                struct ib_client_data *found_context = NULL;
 
                down_write(&lists_rwsem);
-               spin_lock_irq(&device->client_data_lock);
+               write_lock_irq(&device->client_data_lock);
                list_for_each_entry(context, &device->client_data_list, list)
                        if (context->client == client) {
                                context->going_down = true;
                                found_context = context;
                                break;
                        }
-               spin_unlock_irq(&device->client_data_lock);
+               write_unlock_irq(&device->client_data_lock);
                up_write(&lists_rwsem);
 
                if (client->remove)
@@ -699,9 +699,9 @@ void ib_unregister_client(struct ib_client *client)
                }
 
                down_write(&lists_rwsem);
-               spin_lock_irq(&device->client_data_lock);
+               write_lock_irq(&device->client_data_lock);
                list_del(&found_context->list);
-               spin_unlock_irq(&device->client_data_lock);
+               write_unlock_irq(&device->client_data_lock);
                up_write(&lists_rwsem);
                kfree(found_context);
        }
@@ -724,13 +724,13 @@ void *ib_get_client_data(struct ib_device *device, struct ib_client *client)
        void *ret = NULL;
        unsigned long flags;
 
-       spin_lock_irqsave(&device->client_data_lock, flags);
+       read_lock_irqsave(&device->client_data_lock, flags);
        list_for_each_entry(context, &device->client_data_list, list)
                if (context->client == client) {
                        ret = context->data;
                        break;
                }
-       spin_unlock_irqrestore(&device->client_data_lock, flags);
+       read_unlock_irqrestore(&device->client_data_lock, flags);
 
        return ret;
 }
@@ -751,7 +751,7 @@ void ib_set_client_data(struct ib_device *device, struct ib_client *client,
        struct ib_client_data *context;
        unsigned long flags;
 
-       spin_lock_irqsave(&device->client_data_lock, flags);
+       write_lock_irqsave(&device->client_data_lock, flags);
        list_for_each_entry(context, &device->client_data_list, list)
                if (context->client == client) {
                        context->data = data;
@@ -762,7 +762,7 @@ void ib_set_client_data(struct ib_device *device, struct ib_client *client,
                device->name, client->name);
 
 out:
-       spin_unlock_irqrestore(&device->client_data_lock, flags);
+       write_unlock_irqrestore(&device->client_data_lock, flags);
 }
 EXPORT_SYMBOL(ib_set_client_data);
 

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index ddc7c31..995f176 100644 (file)
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -2256,10 +2256,11 @@ struct ib_device {
        struct list_head              event_handler_list;
        spinlock_t                    event_handler_lock;
 
-       spinlock_t                    client_data_lock;
+       rwlock_t                        client_data_lock;
        struct list_head              core_list;
        /* Access to the client_data_list is protected by the client_data_lock
-        * spinlock and the lists_rwsem read-write semaphore */
+        * rwlock and the lists_rwsem read-write semaphore
+        */
        struct list_head              client_data_list;
 
        struct ib_cache               cache;