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>

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 25f93784383699bf86716ba6526add2bf18cf7a3..aa713aade30e548903c1568e81d4c0b8ab56402e 100644 (file)
--- 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 b6621831a58aafa28eb62d79c1f18dda1a326a01..3541b4492f644efa200509e09531b3e0a383bbe6 100644 (file)
--- 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;
        }

diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
index 7f806dcf5278d180deb3ff233bd61cd208a482c9..cbe8a51a21de46426eb669e5545dca778014d179 100644 (file)
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h
@@ -36,7 +36,6 @@
 #define REMOTEPROC_H
 
 #include <linux/types.h>
-#include <linux/kref.h>
 #include <linux/klist.h>
 #include <linux/mutex.h>
 #include <linux/virtio.h>
@@ -370,7 +369,6 @@ enum rproc_state {
  * @priv: private data which belongs to the platform-specific rproc module
  * @ops: platform-specific start/stop rproc handlers
  * @dev: virtual device for refcounting and common remoteproc behavior
- * @refcount: refcount of users that have a valid pointer to this rproc
  * @power: refcount of users who need this rproc powered up
  * @state: state of the device
  * @lock: lock which protects concurrent manipulations of the rproc
@@ -393,7 +391,6 @@ struct rproc {
        void *priv;
        const struct rproc_ops *ops;
        struct device dev;
-       struct kref refcount;
        atomic_t power;
        unsigned int state;
        struct mutex lock;