diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2024-10-17 11:31:34 -0700 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2024-10-24 16:03:40 +0200 |
| commit | 42f5fe1dc4babad1c49bcc4121983fffccee3cd9 (patch) | |
| tree | 6c8061f7470d16d3d140984ca3276abc98de78e4 | |
| parent | 68ed5c38b512b734caf3da1f87db4a99fcfe3002 (diff) | |
phonet: Convert phonet_device_list.lock to spinlock_t.
addr_doit() calls phonet_address_add() or phonet_address_del()
for RTM_NEWADDR or RTM_DELADDR, respectively.
Both functions only touch phonet_device_list(dev_net(dev)),
which is currently protected by RTNL and its dedicated mutex,
phonet_device_list.lock.
We will convert addr_doit() to RCU and cannot use mutex inside RCU.
Let's convert the mutex to spinlock_t.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
| -rw-r--r-- | include/net/phonet/pn_dev.h | 3 | ||||
| -rw-r--r-- | net/phonet/pn_dev.c | 26 |
2 files changed, 19 insertions, 10 deletions
diff --git a/include/net/phonet/pn_dev.h b/include/net/phonet/pn_dev.h index 6b2102b4ece3..ac0331d83a81 100644 --- a/include/net/phonet/pn_dev.h +++ b/include/net/phonet/pn_dev.h @@ -12,12 +12,13 @@ #include <linux/list.h> #include <linux/mutex.h> +#include <linux/spinlock.h> struct net; struct phonet_device_list { struct list_head list; - struct mutex lock; + spinlock_t lock; }; struct phonet_device_list *phonet_device_list(struct net *net); diff --git a/net/phonet/pn_dev.c b/net/phonet/pn_dev.c index 2e7d850dc726..545279ef5910 100644 --- a/net/phonet/pn_dev.c +++ b/net/phonet/pn_dev.c @@ -54,7 +54,7 @@ static struct phonet_device *__phonet_device_alloc(struct net_device *dev) pnd->netdev = dev; bitmap_zero(pnd->addrs, 64); - BUG_ON(!mutex_is_locked(&pndevs->lock)); + lockdep_assert_held(&pndevs->lock); list_add_rcu(&pnd->list, &pndevs->list); return pnd; } @@ -64,7 +64,8 @@ static struct phonet_device *__phonet_get(struct net_device *dev) struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev)); struct phonet_device *pnd; - BUG_ON(!mutex_is_locked(&pndevs->lock)); + lockdep_assert_held(&pndevs->lock); + list_for_each_entry(pnd, &pndevs->list, list) { if (pnd->netdev == dev) return pnd; @@ -91,11 +92,13 @@ static void phonet_device_destroy(struct net_device *dev) ASSERT_RTNL(); - mutex_lock(&pndevs->lock); + spin_lock(&pndevs->lock); + pnd = __phonet_get(dev); if (pnd) list_del_rcu(&pnd->list); - mutex_unlock(&pndevs->lock); + + spin_unlock(&pndevs->lock); if (pnd) { struct net *net = dev_net(dev); @@ -136,7 +139,8 @@ int phonet_address_add(struct net_device *dev, u8 addr) struct phonet_device *pnd; int err = 0; - mutex_lock(&pndevs->lock); + spin_lock(&pndevs->lock); + /* Find or create Phonet-specific device data */ pnd = __phonet_get(dev); if (pnd == NULL) @@ -145,7 +149,9 @@ int phonet_address_add(struct net_device *dev, u8 addr) err = -ENOMEM; else if (test_and_set_bit(addr >> 2, pnd->addrs)) err = -EEXIST; - mutex_unlock(&pndevs->lock); + + spin_unlock(&pndevs->lock); + return err; } @@ -155,7 +161,8 @@ int phonet_address_del(struct net_device *dev, u8 addr) struct phonet_device *pnd; int err = 0; - mutex_lock(&pndevs->lock); + spin_lock(&pndevs->lock); + pnd = __phonet_get(dev); if (!pnd || !test_and_clear_bit(addr >> 2, pnd->addrs)) { err = -EADDRNOTAVAIL; @@ -164,7 +171,8 @@ int phonet_address_del(struct net_device *dev, u8 addr) list_del_rcu(&pnd->list); else pnd = NULL; - mutex_unlock(&pndevs->lock); + + spin_unlock(&pndevs->lock); if (pnd) kfree_rcu(pnd, rcu); @@ -313,7 +321,7 @@ static int __net_init phonet_init_net(struct net *net) return -ENOMEM; INIT_LIST_HEAD(&pnn->pndevs.list); - mutex_init(&pnn->pndevs.lock); + spin_lock_init(&pnn->pndevs.lock); mutex_init(&pnn->routes.lock); return 0; } |