diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2022-04-21 08:33:13 -0700 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2022-04-28 14:01:54 -0700 |
| commit | 3750d013182b071dbf458144540390de0031be8c (patch) | |
| tree | 1c6f6b29a4bd2f1ae1dc6fb522b5c92a56db9b4a /drivers/cxl/core/memdev.c | |
| parent | 56368029d93bbb3246ee2e03268fa6dd9754be05 (diff) | |
cxl: Replace lockdep_mutex with local lock classes
In response to an attempt to expand dev->lockdep_mutex for device_lock()
validation [1], Peter points out [2] that the lockdep API already has
the ability to assign a dedicated lock class per subsystem device-type.
Use lockdep_set_class() to override the default device_lock()
'__lockdep_no_validate__' class for each CXL subsystem device-type. This
enables lockdep to detect deadlocks and recursive locking within the
device-driver core and the subsystem. The
lockdep_set_class_and_subclass() API is used for port objects that
recursively lock the 'cxl_port_key' class by hierarchical topology
depth.
Link: https://lore.kernel.org/r/164982968798.684294.15817853329823976469.stgit@dwillia2-desk3.amr.corp.intel.com [1]
Link: https://lore.kernel.org/r/Ylf0dewci8myLvoW@hirez.programming.kicks-ass.net [2]
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
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/165055519317.3745911.7342499516839702840.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/cxl/core/memdev.c')
| -rw-r--r-- | drivers/cxl/core/memdev.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c index 1f76b28f9826..f7cdcd33504a 100644 --- a/drivers/cxl/core/memdev.c +++ b/drivers/cxl/core/memdev.c @@ -228,6 +228,8 @@ static void detach_memdev(struct work_struct *work) put_device(&cxlmd->dev); } +static struct lock_class_key cxl_memdev_key; + static struct cxl_memdev *cxl_memdev_alloc(struct cxl_dev_state *cxlds, const struct file_operations *fops) { @@ -247,6 +249,7 @@ static struct cxl_memdev *cxl_memdev_alloc(struct cxl_dev_state *cxlds, dev = &cxlmd->dev; device_initialize(dev); + lockdep_set_class(&dev->mutex, &cxl_memdev_key); dev->parent = cxlds->dev; dev->bus = &cxl_bus_type; dev->devt = MKDEV(cxl_mem_major, cxlmd->id); |