ipvs: change ip_vs_sched_lock to mutex

The global list with schedulers ip_vs_schedulers
is accessed only from user context - configuration and
scheduler module [un]registration. Use ip_vs_sched_mutex
instead.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>

diff --git a/net/netfilter/ipvs/ip_vs_sched.c b/net/netfilter/ipvs/ip_vs_sched.c
index d6bf20d..7f11d3d 100644 (file)
--- a/net/netfilter/ipvs/ip_vs_sched.c
+++ b/net/netfilter/ipvs/ip_vs_sched.c
@@ -35,8 +35,8 @@ EXPORT_SYMBOL(ip_vs_scheduler_err);
  */
 static LIST_HEAD(ip_vs_schedulers);
 
-/* lock for service table */
-static DEFINE_SPINLOCK(ip_vs_sched_lock);
+/* semaphore for schedulers */
+static DEFINE_MUTEX(ip_vs_sched_mutex);
 
 
 /*
@@ -92,7 +92,7 @@ static struct ip_vs_scheduler *ip_vs_sched_getbyname(const char *sched_name)
 
        IP_VS_DBG(2, "%s(): sched_name \"%s\"\n", __func__, sched_name);
 
-       spin_lock_bh(&ip_vs_sched_lock);
+       mutex_lock(&ip_vs_sched_mutex);
 
        list_for_each_entry(sched, &ip_vs_schedulers, n_list) {
                /*
@@ -106,14 +106,14 @@ static struct ip_vs_scheduler *ip_vs_sched_getbyname(const char *sched_name)
                }
                if (strcmp(sched_name, sched->name)==0) {
                        /* HIT */
-                       spin_unlock_bh(&ip_vs_sched_lock);
+                       mutex_unlock(&ip_vs_sched_mutex);
                        return sched;
                }
                if (sched->module)
                        module_put(sched->module);
        }
 
-       spin_unlock_bh(&ip_vs_sched_lock);
+       mutex_unlock(&ip_vs_sched_mutex);
        return NULL;
 }
 
@@ -192,10 +192,10 @@ int register_ip_vs_scheduler(struct ip_vs_scheduler *scheduler)
        /* increase the module use count */
        ip_vs_use_count_inc();
 
-       spin_lock_bh(&ip_vs_sched_lock);
+       mutex_lock(&ip_vs_sched_mutex);
 
        if (!list_empty(&scheduler->n_list)) {
-               spin_unlock_bh(&ip_vs_sched_lock);
+               mutex_unlock(&ip_vs_sched_mutex);
                ip_vs_use_count_dec();
                pr_err("%s(): [%s] scheduler already linked\n",
                       __func__, scheduler->name);
@@ -208,7 +208,7 @@ int register_ip_vs_scheduler(struct ip_vs_scheduler *scheduler)
         */
        list_for_each_entry(sched, &ip_vs_schedulers, n_list) {
                if (strcmp(scheduler->name, sched->name) == 0) {
-                       spin_unlock_bh(&ip_vs_sched_lock);
+                       mutex_unlock(&ip_vs_sched_mutex);
                        ip_vs_use_count_dec();
                        pr_err("%s(): [%s] scheduler already existed "
                               "in the system\n", __func__, scheduler->name);
@@ -219,7 +219,7 @@ int register_ip_vs_scheduler(struct ip_vs_scheduler *scheduler)
         *      Add it into the d-linked scheduler list
         */
        list_add(&scheduler->n_list, &ip_vs_schedulers);
-       spin_unlock_bh(&ip_vs_sched_lock);
+       mutex_unlock(&ip_vs_sched_mutex);
 
        pr_info("[%s] scheduler registered.\n", scheduler->name);
 
@@ -237,9 +237,9 @@ int unregister_ip_vs_scheduler(struct ip_vs_scheduler *scheduler)
                return -EINVAL;
        }
 
-       spin_lock_bh(&ip_vs_sched_lock);
+       mutex_lock(&ip_vs_sched_mutex);
        if (list_empty(&scheduler->n_list)) {
-               spin_unlock_bh(&ip_vs_sched_lock);
+               mutex_unlock(&ip_vs_sched_mutex);
                pr_err("%s(): [%s] scheduler is not in the list. failed\n",
                       __func__, scheduler->name);
                return -EINVAL;
@@ -249,7 +249,7 @@ int unregister_ip_vs_scheduler(struct ip_vs_scheduler *scheduler)
         *      Remove it from the d-linked scheduler list
         */
        list_del(&scheduler->n_list);
-       spin_unlock_bh(&ip_vs_sched_lock);
+       mutex_unlock(&ip_vs_sched_mutex);
 
        /* decrease the module use count */
        ip_vs_use_count_dec();