device-core: Kill the lockdep_mutex

Per Peter [1], the lockdep API has native support for all the use cases
lockdep_mutex was attempting to enable. Now that all lockdep_mutex users
have been converted to those APIs, drop this lock.

Link: https://lore.kernel.org/r/Ylf0dewci8myLvoW@hirez.programming.kicks-ass.net
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/165055522548.3745911.14298368286915484086.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 3d6430e..2eede2e 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -2864,9 +2864,6 @@ void device_initialize(struct device *dev)
        kobject_init(&dev->kobj, &device_ktype);
        INIT_LIST_HEAD(&dev->dma_pools);
        mutex_init(&dev->mutex);
-#ifdef CONFIG_PROVE_LOCKING
-       mutex_init(&dev->lockdep_mutex);
-#endif
        lockdep_set_novalidate_class(&dev->mutex);
        spin_lock_init(&dev->devres_lock);
        INIT_LIST_HEAD(&dev->devres_head);

diff --git a/include/linux/device.h b/include/linux/device.h
index 833b0b3..073f1b0 100644 (file)
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -400,8 +400,6 @@ struct dev_msi_info {
  *             This identifies the device type and carries type-specific
  *             information.
  * @mutex:     Mutex to synchronize calls to its driver.
- * @lockdep_mutex: An optional debug lock that a subsystem can use as a
- *             peer lock to gain localized lockdep coverage of the device_lock.
  * @bus:       Type of bus device is on.
  * @driver:    Which driver has allocated this
  * @platform_data: Platform data specific to the device.
@@ -499,9 +497,6 @@ struct device {
                                           core doesn't touch it */
        void            *driver_data;   /* Driver data, set and get with
                                           dev_set_drvdata/dev_get_drvdata */
-#ifdef CONFIG_PROVE_LOCKING
-       struct mutex            lockdep_mutex;
-#endif
        struct mutex            mutex;  /* mutex to synchronize calls to
                                         * its driver.
                                         */