ieee802154: rework wpan_phy index assignment
This patch reworks the wpan_phy index incrementation. It's now similar
like wireless wiphy index incrementation. We move the wpan_phy index
attribute inside of cfg802154_registered_device and use atomic
operations instead locking mechanism via wpan_phy_mutex.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/include/net/cfg802154.h b/include/net/cfg802154.h
index 864bce2..29c6de5 100644
--- a/include/net/cfg802154.h
+++ b/include/net/cfg802154.h
@@ -61,7 +61,6 @@
s32 cca_ed_level;
struct device dev;
- int idx;
char priv[0] __aligned(NETDEV_ALIGN);
};
diff --git a/net/ieee802154/core.c b/net/ieee802154/core.c
index ed5b014..d1cd0ed 100644
--- a/net/ieee802154/core.c
+++ b/net/ieee802154/core.c
@@ -23,9 +23,6 @@
#include "sysfs.h"
#include "core.h"
-static DEFINE_MUTEX(wpan_phy_mutex);
-static int wpan_phy_idx;
-
static int wpan_phy_match(struct device *dev, const void *data)
{
return !strcmp(dev_name(dev), (const char *)data);
@@ -72,14 +69,10 @@
}
EXPORT_SYMBOL(wpan_phy_for_each);
-static int wpan_phy_idx_valid(int idx)
-{
- return idx >= 0;
-}
-
struct wpan_phy *
wpan_phy_alloc(const struct cfg802154_ops *ops, size_t priv_size)
{
+ static atomic_t wpan_phy_counter = ATOMIC_INIT(0);
struct cfg802154_registered_device *rdev;
size_t alloc_size;
@@ -90,28 +83,27 @@
rdev->ops = ops;
- mutex_lock(&wpan_phy_mutex);
- rdev->wpan_phy.idx = wpan_phy_idx++;
- if (unlikely(!wpan_phy_idx_valid(rdev->wpan_phy.idx))) {
- wpan_phy_idx--;
- mutex_unlock(&wpan_phy_mutex);
+ rdev->wpan_phy_idx = atomic_inc_return(&wpan_phy_counter);
+
+ if (unlikely(rdev->wpan_phy_idx < 0)) {
+ /* ugh, wrapped! */
+ atomic_dec(&wpan_phy_counter);
kfree(rdev);
- goto out;
+ return NULL;
}
- mutex_unlock(&wpan_phy_mutex);
+
+ /* atomic_inc_return makes it start at 1, make it start at 0 */
+ rdev->wpan_phy_idx--;
mutex_init(&rdev->wpan_phy.pib_lock);
device_initialize(&rdev->wpan_phy.dev);
- dev_set_name(&rdev->wpan_phy.dev, "wpan-phy%d", rdev->wpan_phy.idx);
+ dev_set_name(&rdev->wpan_phy.dev, "wpan-phy%d", rdev->wpan_phy_idx);
rdev->wpan_phy.dev.class = &wpan_phy_class;
rdev->wpan_phy.dev.platform_data = rdev;
return &rdev->wpan_phy;
-
-out:
- return NULL;
}
EXPORT_SYMBOL(wpan_phy_alloc);
diff --git a/net/ieee802154/core.h b/net/ieee802154/core.h
index 1bc1725..fea60b3 100644
--- a/net/ieee802154/core.h
+++ b/net/ieee802154/core.h
@@ -6,6 +6,9 @@
struct cfg802154_registered_device {
const struct cfg802154_ops *ops;
+ /* wpan_phy index, internal only */
+ int wpan_phy_idx;
+
/* must be last because of the way we do wpan_phy_priv(),
* and it should at least be aligned to NETDEV_ALIGN
*/