RDMA/devices: Remove the lock around remove_client_context (9cd58817) · Commits · 戴 / test

drivers/infiniband/core/device.c

+27 −21

Original line number	Diff line number	Diff line
		@@ -94,7 +94,7 @@ static DEFINE_XARRAY_FLAGS(devices, XA_FLAGS_ALLOC);
		static DECLARE_RWSEM(devices_rwsem);
		#define DEVICE_REGISTERED XA_MARK_1

		static LIST_HEAD(client_list);
		static u32 highest_client_id;
		#define CLIENT_REGISTERED XA_MARK_1
		static DEFINE_XARRAY_FLAGS(clients, XA_FLAGS_ALLOC);
		static DECLARE_RWSEM(clients_rwsem);
		@@ -1237,7 +1237,7 @@ static int setup_device(struct ib_device *device)

		static void disable_device(struct ib_device *device)
		{
		struct ib_client *client;
		u32 cid;

		WARN_ON(!refcount_read(&device->refcount));

		@@ -1245,10 +1245,19 @@ static void disable_device(struct ib_device *device)
		xa_clear_mark(&devices, device->index, DEVICE_REGISTERED);
		up_write(&devices_rwsem);

		/*
		* Remove clients in LIFO order, see assign_client_id. This could be
		* more efficient if xarray learns to reverse iterate. Since no new
		* clients can be added to this ib_device past this point we only need
		* the maximum possible client_id value here.
		*/
		down_read(&clients_rwsem);
		list_for_each_entry_reverse(client, &client_list, list)
		remove_client_context(device, client->client_id);
		cid = highest_client_id;
		up_read(&clients_rwsem);
		while (cid) {
		cid--;
		remove_client_context(device, cid);
		}

		/* Pairs with refcount_set in enable_device */
		ib_device_put(device);
		@@ -1675,30 +1684,31 @@ static int assign_client_id(struct ib_client *client)
		/*
		* The add/remove callbacks must be called in FIFO/LIFO order. To
		* achieve this we assign client_ids so they are sorted in
		* registration order, and retain a linked list we can reverse iterate
		* to get the LIFO order. The extra linked list can go away if xarray
		* learns to reverse iterate.
		* registration order.
		*/
		if (list_empty(&client_list)) {
		client->client_id = 0;
		} else {
		struct ib_client *last;

		last = list_last_entry(&client_list, struct ib_client, list);
		client->client_id = last->client_id + 1;
		}
		client->client_id = highest_client_id;
		ret = xa_insert(&clients, client->client_id, client, GFP_KERNEL);
		if (ret)
		goto out;

		highest_client_id++;
		xa_set_mark(&clients, client->client_id, CLIENT_REGISTERED);
		list_add_tail(&client->list, &client_list);

		out:
		up_write(&clients_rwsem);
		return ret;
		}

		static void remove_client_id(struct ib_client *client)
		{
		down_write(&clients_rwsem);
		xa_erase(&clients, client->client_id);
		for (; highest_client_id; highest_client_id--)
		if (xa_load(&clients, highest_client_id - 1))
		break;
		up_write(&clients_rwsem);
		}

		/**
		* ib_register_client - Register an IB client
		* @client:Client to register
		@@ -1778,11 +1788,7 @@ void ib_unregister_client(struct ib_client *client)
		* removal is ongoing. Wait until all removals are completed.
		*/
		wait_for_completion(&client->uses_zero);

		down_write(&clients_rwsem);
		list_del(&client->list);
		xa_erase(&clients, client->client_id);
		up_write(&clients_rwsem);
		remove_client_id(client);
		}
		EXPORT_SYMBOL(ib_unregister_client);

include/rdma/ib_verbs.h

+0 −1

Original line number	Diff line number	Diff line
		@@ -2650,7 +2650,6 @@ struct ib_client {

		refcount_t uses;
		struct completion uses_zero;
		struct list_head list;
		u32 client_id;

		/* kverbs are not required by the client */

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