diff options
author | Alexander Aring <alex.aring@gmail.com> | 2014-11-05 20:51:12 +0100 |
---|---|---|
committer | Marcel Holtmann <marcel@holtmann.org> | 2014-11-05 21:53:03 +0100 |
commit | 53f9ee61b46d81a43d8c6694d136896e8f49a7b8 (patch) | |
tree | d6d98d0ad30cb084516cbbc741425f95c0dee46c /net/ieee802154/core.c | |
parent | 0d8a52f933f817d0b62955a5a362fb7f2508f06c (diff) | |
download | linux-53f9ee61b46d81a43d8c6694d136896e8f49a7b8.tar.bz2 |
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>
Diffstat (limited to 'net/ieee802154/core.c')
-rw-r--r-- | net/ieee802154/core.c | 30 |
1 files changed, 11 insertions, 19 deletions
diff --git a/net/ieee802154/core.c b/net/ieee802154/core.c index ed5b014dbec7..d1cd0edfb149 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 @@ int wpan_phy_for_each(int (*fn)(struct wpan_phy *phy, void *data), } 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 @@ wpan_phy_alloc(const struct cfg802154_ops *ops, size_t priv_size) 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); |