[NETFILTER]: nf_log: switch logger registration/unregistration to mutex

The spinlock is only used in process context (register/unregister),
switch to a mutex.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick McHardy 2007-02-12 11:11:39 -08:00 committed by David S. Miller
parent 9dc6aa5fcf
commit 9b73534dc5

View file

@ -15,27 +15,31 @@
#define NF_LOG_PREFIXLEN 128
static struct nf_logger *nf_logging[NPROTO]; /* = NULL */
static DEFINE_SPINLOCK(nf_log_lock);
static DEFINE_MUTEX(nf_log_mutex);
/* return EBUSY if somebody else is registered, EEXIST if the same logger
* is registred, 0 on success. */
int nf_log_register(int pf, struct nf_logger *logger)
{
int ret = -EBUSY;
int ret;
if (pf >= NPROTO)
return -EINVAL;
/* Any setup of logging members must be done before
* substituting pointer. */
spin_lock(&nf_log_lock);
if (!nf_logging[pf]) {
rcu_assign_pointer(nf_logging[pf], logger);
ret = 0;
} else if (nf_logging[pf] == logger)
ret = -EEXIST;
ret = mutex_lock_interruptible(&nf_log_mutex);
if (ret < 0)
return ret;
spin_unlock(&nf_log_lock);
if (!nf_logging[pf])
rcu_assign_pointer(nf_logging[pf], logger);
else if (nf_logging[pf] == logger)
ret = -EEXIST;
else
ret = -EBUSY;
mutex_unlock(&nf_log_mutex);
return ret;
}
EXPORT_SYMBOL(nf_log_register);
@ -44,9 +48,9 @@ void nf_log_unregister_pf(int pf)
{
if (pf >= NPROTO)
return;
spin_lock(&nf_log_lock);
mutex_lock(&nf_log_mutex);
rcu_assign_pointer(nf_logging[pf], NULL);
spin_unlock(&nf_log_lock);
mutex_unlock(&nf_log_mutex);
/* Give time to concurrent readers. */
synchronize_rcu();
@ -57,12 +61,12 @@ void nf_log_unregister_logger(struct nf_logger *logger)
{
int i;
spin_lock(&nf_log_lock);
mutex_lock(&nf_log_mutex);
for (i = 0; i < NPROTO; i++) {
if (nf_logging[i] == logger)
rcu_assign_pointer(nf_logging[i], NULL);
}
spin_unlock(&nf_log_lock);
mutex_unlock(&nf_log_mutex);
synchronize_rcu();
}