cxl: Drop cxl_device_lock()

Now that all CXL subsystem locking is validated with custom lock
classes, there is no need for the custom usage of the lockdep_mutex.

Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Ben Widawsky <ben.widawsky@intel.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/165055520383.3745911.53447786039115271.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c
index e825e26..bec7cfb 100644 (file)
--- a/drivers/cxl/core/pmem.c
+++ b/drivers/cxl/core/pmem.c
@@ -124,10 +124,10 @@ static void unregister_nvb(void *_cxl_nvb)
         * work to flush. Once the state has been changed to 'dead' then no new
         * work can be queued by user-triggered bind.
         */
-       cxl_device_lock(&cxl_nvb->dev);
+       device_lock(&cxl_nvb->dev);
        flush = cxl_nvb->state != CXL_NVB_NEW;
        cxl_nvb->state = CXL_NVB_DEAD;
-       cxl_device_unlock(&cxl_nvb->dev);
+       device_unlock(&cxl_nvb->dev);
 
        /*
         * Even though the device core will trigger device_release_driver()

diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
index 750aac9..ea60abd 100644 (file)
--- a/drivers/cxl/core/port.c
+++ b/drivers/cxl/core/port.c
@@ -312,10 +312,10 @@ static void cxl_port_release(struct device *dev)
        struct cxl_port *port = to_cxl_port(dev);
        struct cxl_ep *ep, *_e;
 
-       cxl_device_lock(dev);
+       device_lock(dev);
        list_for_each_entry_safe(ep, _e, &port->endpoints, list)
                cxl_ep_release(ep);
-       cxl_device_unlock(dev);
+       device_unlock(dev);
        ida_free(&cxl_port_ida, port->id);
        kfree(port);
 }
@@ -556,7 +556,7 @@ static int match_root_child(struct device *dev, const void *match)
                return 0;
 
        port = to_cxl_port(dev);
-       cxl_device_lock(dev);
+       device_lock(dev);
        list_for_each_entry(dport, &port->dports, list) {
                iter = match;
                while (iter) {
@@ -566,7 +566,7 @@ static int match_root_child(struct device *dev, const void *match)
                }
        }
 out:
-       cxl_device_unlock(dev);
+       device_unlock(dev);
 
        return !!iter;
 }
@@ -625,13 +625,13 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new)
 static void cond_cxl_root_lock(struct cxl_port *port)
 {
        if (is_cxl_root(port))
-               cxl_device_lock(&port->dev);
+               device_lock(&port->dev);
 }
 
 static void cond_cxl_root_unlock(struct cxl_port *port)
 {
        if (is_cxl_root(port))
-               cxl_device_unlock(&port->dev);
+               device_unlock(&port->dev);
 }
 
 static void cxl_dport_remove(void *data)
@@ -738,15 +738,15 @@ static int add_ep(struct cxl_port *port, struct cxl_ep *new)
 {
        struct cxl_ep *dup;
 
-       cxl_device_lock(&port->dev);
+       device_lock(&port->dev);
        if (port->dead) {
-               cxl_device_unlock(&port->dev);
+               device_unlock(&port->dev);
                return -ENXIO;
        }
        dup = find_ep(port, new->ep);
        if (!dup)
                list_add_tail(&new->list, &port->endpoints);
-       cxl_device_unlock(&port->dev);
+       device_unlock(&port->dev);
 
        return dup ? -EEXIST : 0;
 }
@@ -856,12 +856,12 @@ static void delete_endpoint(void *data)
                goto out;
        parent = &parent_port->dev;
 
-       cxl_device_lock(parent);
+       device_lock(parent);
        if (parent->driver && endpoint->uport) {
                devm_release_action(parent, cxl_unlink_uport, endpoint);
                devm_release_action(parent, unregister_port, endpoint);
        }
-       cxl_device_unlock(parent);
+       device_unlock(parent);
        put_device(parent);
 out:
        put_device(&endpoint->dev);
@@ -922,7 +922,7 @@ static void cxl_detach_ep(void *data)
                }
 
                parent_port = to_cxl_port(port->dev.parent);
-               cxl_device_lock(&parent_port->dev);
+               device_lock(&parent_port->dev);
                if (!parent_port->dev.driver) {
                        /*
                         * The bottom-up race to delete the port lost to a
@@ -930,12 +930,12 @@ static void cxl_detach_ep(void *data)
                         * parent_port ->remove() will have cleaned up all
                         * descendants.
                         */
-                       cxl_device_unlock(&parent_port->dev);
+                       device_unlock(&parent_port->dev);
                        put_device(&port->dev);
                        continue;
                }
 
-               cxl_device_lock(&port->dev);
+               device_lock(&port->dev);
                ep = find_ep(port, &cxlmd->dev);
                dev_dbg(&cxlmd->dev, "disconnect %s from %s\n",
                        ep ? dev_name(ep->ep) : "", dev_name(&port->dev));
@@ -950,7 +950,7 @@ static void cxl_detach_ep(void *data)
                        port->dead = true;
                        list_splice_init(&port->dports, &reap_dports);
                }
-               cxl_device_unlock(&port->dev);
+               device_unlock(&port->dev);
 
                if (!list_empty(&reap_dports)) {
                        dev_dbg(&cxlmd->dev, "delete %s\n",
@@ -958,7 +958,7 @@ static void cxl_detach_ep(void *data)
                        delete_switch_port(port, &reap_dports);
                }
                put_device(&port->dev);
-               cxl_device_unlock(&parent_port->dev);
+               device_unlock(&parent_port->dev);
        }
 }
 
@@ -1006,7 +1006,7 @@ static int add_port_attach_ep(struct cxl_memdev *cxlmd,
                return -EAGAIN;
        }
 
-       cxl_device_lock(&parent_port->dev);
+       device_lock(&parent_port->dev);
        if (!parent_port->dev.driver) {
                dev_warn(&cxlmd->dev,
                         "port %s:%s disabled, failed to enumerate CXL.mem\n",
@@ -1024,7 +1024,7 @@ static int add_port_attach_ep(struct cxl_memdev *cxlmd,
                        get_device(&port->dev);
        }
 out:
-       cxl_device_unlock(&parent_port->dev);
+       device_unlock(&parent_port->dev);
 
        if (IS_ERR(port))
                rc = PTR_ERR(port);
@@ -1135,14 +1135,14 @@ struct cxl_dport *cxl_find_dport_by_dev(struct cxl_port *port,
 {
        struct cxl_dport *dport;
 
-       cxl_device_lock(&port->dev);
+       device_lock(&port->dev);
        list_for_each_entry(dport, &port->dports, list)
                if (dport->dport == dev) {
-                       cxl_device_unlock(&port->dev);
+                       device_unlock(&port->dev);
                        return dport;
                }
 
-       cxl_device_unlock(&port->dev);
+       device_unlock(&port->dev);
        return NULL;
 }
 EXPORT_SYMBOL_NS_GPL(cxl_find_dport_by_dev, CXL);
@@ -1384,9 +1384,9 @@ int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map)
 
        port = to_cxl_port(cxld->dev.parent);
 
-       cxl_device_lock(&port->dev);
+       device_lock(&port->dev);
        rc = cxl_decoder_add_locked(cxld, target_map);
-       cxl_device_unlock(&port->dev);
+       device_unlock(&port->dev);
 
        return rc;
 }
@@ -1457,14 +1457,7 @@ static int cxl_bus_probe(struct device *dev)
 {
        int rc;
 
-       /*
-        * Take the CXL nested lock since the driver core only holds
-        * @dev->mutex and not @dev->lockdep_mutex.
-        */
-       cxl_nested_lock(dev);
        rc = to_cxl_drv(dev->driver)->probe(dev);
-       cxl_nested_unlock(dev);
-
        dev_dbg(dev, "probe: %d\n", rc);
        return rc;
 }
@@ -1473,10 +1466,8 @@ static void cxl_bus_remove(struct device *dev)
 {
        struct cxl_driver *cxl_drv = to_cxl_drv(dev->driver);
 
-       cxl_nested_lock(dev);
        if (cxl_drv->remove)
                cxl_drv->remove(dev);
-       cxl_nested_unlock(dev);
 }
 
 static struct workqueue_struct *cxl_bus_wq;

diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 990b667..140dc32 100644 (file)
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -405,82 +405,4 @@ struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_nvdimm *cxl_nvd);
 #define __mock static
 #endif
 
-#ifdef CONFIG_PROVE_CXL_LOCKING
-enum cxl_lock_class {
-       CXL_ANON_LOCK,
-       CXL_NVDIMM_LOCK,
-       CXL_NVDIMM_BRIDGE_LOCK,
-       CXL_PORT_LOCK,
-       /*
-        * Be careful to add new lock classes here, CXL_PORT_LOCK is
-        * extended by the port depth, so a maximum CXL port topology
-        * depth would need to be defined first.
-        */
-};
-
-static inline void cxl_nested_lock(struct device *dev)
-{
-       if (is_cxl_port(dev)) {
-               struct cxl_port *port = to_cxl_port(dev);
-
-               mutex_lock_nested(&dev->lockdep_mutex,
-                                 CXL_PORT_LOCK + port->depth);
-       } else if (is_cxl_decoder(dev)) {
-               struct cxl_port *port = to_cxl_port(dev->parent);
-
-               /*
-                * A decoder is the immediate child of a port, so set
-                * its lock class equal to other child device siblings.
-                */
-               mutex_lock_nested(&dev->lockdep_mutex,
-                                 CXL_PORT_LOCK + port->depth + 1);
-       } else if (is_cxl_nvdimm_bridge(dev))
-               mutex_lock_nested(&dev->lockdep_mutex, CXL_NVDIMM_BRIDGE_LOCK);
-       else if (is_cxl_nvdimm(dev))
-               mutex_lock_nested(&dev->lockdep_mutex, CXL_NVDIMM_LOCK);
-       else
-               mutex_lock_nested(&dev->lockdep_mutex, CXL_ANON_LOCK);
-}
-
-static inline void cxl_nested_unlock(struct device *dev)
-{
-       mutex_unlock(&dev->lockdep_mutex);
-}
-
-static inline void cxl_device_lock(struct device *dev)
-{
-       /*
-        * For double lock errors the lockup will happen before lockdep
-        * warns at cxl_nested_lock(), so assert explicitly.
-        */
-       lockdep_assert_not_held(&dev->lockdep_mutex);
-
-       device_lock(dev);
-       cxl_nested_lock(dev);
-}
-
-static inline void cxl_device_unlock(struct device *dev)
-{
-       cxl_nested_unlock(dev);
-       device_unlock(dev);
-}
-#else
-static inline void cxl_nested_lock(struct device *dev)
-{
-}
-
-static inline void cxl_nested_unlock(struct device *dev)
-{
-}
-
-static inline void cxl_device_lock(struct device *dev)
-{
-       device_lock(dev);
-}
-
-static inline void cxl_device_unlock(struct device *dev)
-{
-       device_unlock(dev);
-}
-#endif
 #endif /* __CXL_H__ */

diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
index 1bd2e0b..401b0fb 100644 (file)
--- a/drivers/cxl/mem.c
+++ b/drivers/cxl/mem.c
@@ -187,7 +187,7 @@ static int cxl_mem_probe(struct device *dev)
                return -ENXIO;
        }
 
-       cxl_device_lock(&parent_port->dev);
+       device_lock(&parent_port->dev);
        if (!parent_port->dev.driver) {
                dev_err(dev, "CXL port topology %s not enabled\n",
                        dev_name(&parent_port->dev));
@@ -197,7 +197,7 @@ static int cxl_mem_probe(struct device *dev)
 
        rc = create_endpoint(cxlmd, parent_port);
 out:
-       cxl_device_unlock(&parent_port->dev);
+       device_unlock(&parent_port->dev);
        put_device(&parent_port->dev);
 
        /*

diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c
index 404018d..bbeef91 100644 (file)
--- a/drivers/cxl/pmem.c
+++ b/drivers/cxl/pmem.c
@@ -43,7 +43,7 @@ static int cxl_nvdimm_probe(struct device *dev)
        if (!cxl_nvb)
                return -ENXIO;
 
-       cxl_device_lock(&cxl_nvb->dev);
+       device_lock(&cxl_nvb->dev);
        if (!cxl_nvb->nvdimm_bus) {
                rc = -ENXIO;
                goto out;
@@ -68,7 +68,7 @@ static int cxl_nvdimm_probe(struct device *dev)
        dev_set_drvdata(dev, nvdimm);
        rc = devm_add_action_or_reset(dev, unregister_nvdimm, nvdimm);
 out:
-       cxl_device_unlock(&cxl_nvb->dev);
+       device_unlock(&cxl_nvb->dev);
        put_device(&cxl_nvb->dev);
 
        return rc;
@@ -233,7 +233,7 @@ static void cxl_nvb_update_state(struct work_struct *work)
        struct nvdimm_bus *victim_bus = NULL;
        bool release = false, rescan = false;
 
-       cxl_device_lock(&cxl_nvb->dev);
+       device_lock(&cxl_nvb->dev);
        switch (cxl_nvb->state) {
        case CXL_NVB_ONLINE:
                if (!online_nvdimm_bus(cxl_nvb)) {
@@ -251,7 +251,7 @@ static void cxl_nvb_update_state(struct work_struct *work)
        default:
                break;
        }
-       cxl_device_unlock(&cxl_nvb->dev);
+       device_unlock(&cxl_nvb->dev);
 
        if (release)
                device_release_driver(&cxl_nvb->dev);
@@ -327,9 +327,9 @@ static int cxl_nvdimm_bridge_reset(struct device *dev, void *data)
                return 0;
 
        cxl_nvb = to_cxl_nvdimm_bridge(dev);
-       cxl_device_lock(dev);
+       device_lock(dev);
        cxl_nvb->state = CXL_NVB_NEW;
-       cxl_device_unlock(dev);
+       device_unlock(dev);
 
        return 0;
 }

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 075cd25..4a2c853 100644 (file)
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1559,12 +1559,6 @@ config PROVE_NVDIMM_LOCKING
        help
          Enable lockdep to validate nd_device_lock() usage.
 
-config PROVE_CXL_LOCKING
-       bool "CXL"
-       depends on CXL_BUS
-       help
-         Enable lockdep to validate cxl_device_lock() usage.
-
 endchoice
 
 endmenu # lock debugging