remoteproc: remove the now-redundant kref

Now that every rproc instance contains a device, we don't need a
kref anymore to maintain the refcount of the rproc instances:
that's what device are good with!

This patch removes the now-redundant kref, and switches to
{get, put}_device instead of kref_{get, put}.

We also don't need the kref's release function anymore, and instead,
we just utilize the class's release handler (which is now responsible
for all memory de-allocations).

Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Fernando Guzman Lugo <fernando.lugo@ti.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>

2 files changed, 15 insertions, 43 deletions

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 25f937843836..aa713aade30e 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -1257,42 +1257,12 @@ out:
 }
 EXPORT_SYMBOL(rproc_shutdown);
 
-/**
- * rproc_release() - completely deletes the existence of a remote processor
- * @kref: the rproc's kref
- *
- * This function should _never_ be called directly.
- *
- * The only reasonable location to use it is as an argument when kref_put'ing
- * @rproc's refcount.
- *
- * This way it will be called when no one holds a valid pointer to this @rproc
- * anymore (and obviously after it is removed from the rprocs klist).
- *
- * Note: this function is not static because rproc_vdev_release() needs it when
- * it decrements @rproc's refcount.
- */
-void rproc_release(struct kref *kref)
-{
-        struct rproc *rproc = container_of(kref, struct rproc, refcount);
-
-        dev_info(&rproc->dev, "removing %s\n", rproc->name);
-
-        rproc_delete_debug_dir(rproc);
-
-        /*
-         * At this point no one holds a reference to rproc anymore,
-         * so we can directly unroll rproc_alloc()
-         */
-        rproc_free(rproc);
-}
-
 /* will be called when an rproc is added to the rprocs klist */
 static void klist_rproc_get(struct klist_node *n)
 {
         struct rproc *rproc = container_of(n, struct rproc, node);
 
-        kref_get(&rproc->refcount);
+        get_device(&rproc->dev);
 }
 
 /* will be called when an rproc is removed from the rprocs klist */
@@ -1300,7 +1270,7 @@ static void klist_rproc_put(struct klist_node *n)
 {
         struct rproc *rproc = container_of(n, struct rproc, node);
 
-        kref_put(&rproc->refcount, rproc_release);
+        put_device(&rproc->dev);
 }
 
 static struct rproc *next_rproc(struct klist_iter *i)
@@ -1342,7 +1312,7 @@ struct rproc *rproc_get_by_name(const char *name)
         klist_iter_init(&rprocs, &i);
         while ((rproc = next_rproc(&i)) != NULL)
                 if (!strcmp(rproc->name, name)) {
-                        kref_get(&rproc->refcount);
+                        get_device(&rproc->dev);
                         break;
                 }
         klist_iter_exit(&i);
@@ -1355,7 +1325,7 @@ struct rproc *rproc_get_by_name(const char *name)
 
         ret = rproc_boot(rproc);
         if (ret < 0) {
-                kref_put(&rproc->refcount, rproc_release);
+                put_device(&rproc->dev);
                 return NULL;
         }
 
@@ -1382,7 +1352,7 @@ void rproc_put(struct rproc *rproc)
         rproc_shutdown(rproc);
 
         /* downref rproc's refcount */
-        kref_put(&rproc->refcount, rproc_release);
+        put_device(&rproc->dev);
 }
 EXPORT_SYMBOL(rproc_put);
 
@@ -1463,6 +1433,10 @@ static void rproc_type_release(struct device *dev)
 {
         struct rproc *rproc = container_of(dev, struct rproc, dev);
 
+        dev_info(&rproc->dev, "releasing %s\n", rproc->name);
+
+        rproc_delete_debug_dir(rproc);
+
         idr_remove_all(&rproc->notifyids);
         idr_destroy(&rproc->notifyids);
 
@@ -1536,8 +1510,6 @@ struct rproc *rproc_alloc(struct device *dev, const char *name,
 
         atomic_set(&rproc->power, 0);
 
-        kref_init(&rproc->refcount);
-
         mutex_init(&rproc->lock);
 
         idr_init(&rproc->notifyids);
@@ -1608,8 +1580,8 @@ int rproc_unregister(struct rproc *rproc)
 
         device_del(&rproc->dev);
 
-        /* the rproc will only be released after its refcount drops to zero */
-        kref_put(&rproc->refcount, rproc_release);
+        /* unroll rproc_alloc. TODO: we may want to let the users do that */
+        put_device(&rproc->dev);
 
         return 0;
 }
diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c
index b6621831a58a..3541b4492f64 100644
--- a/drivers/remoteproc/remoteproc_virtio.c
+++ b/drivers/remoteproc/remoteproc_virtio.c
@@ -225,7 +225,7 @@ static struct virtio_config_ops rproc_virtio_config_ops = {
 
 /*
  * This function is called whenever vdev is released, and is responsible
- * to decrement the remote processor's refcount taken when vdev was
+ * to decrement the remote processor's refcount which was taken when vdev was
  * added.
  *
  * Never call this function directly; it will be called by the driver
@@ -240,7 +240,7 @@ static void rproc_vdev_release(struct device *dev)
         list_del(&rvdev->node);
         kfree(rvdev);
 
-        kref_put(&rproc->refcount, rproc_release);
+        put_device(&rproc->dev);
 }
 
 /**
@@ -272,11 +272,11 @@ int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)
          * Therefore we must increment the rproc refcount here, and decrement
          * it _only_ when the vdev is released.
          */
-        kref_get(&rproc->refcount);
+        get_device(&rproc->dev);
 
         ret = register_virtio_device(vdev);
         if (ret) {
-                kref_put(&rproc->refcount, rproc_release);
+                put_device(&rproc->dev);
                 dev_err(dev, "failed to register vdev: %d\n", ret);
                 goto out;
         }