ipvs: Create init functions for estimator code

Commit 8ab19ea36c5c5340ff598e4d15fc084eb65671dc ("ipvs: Fix possible deadlock
in estimator code") fixed a deadlock condition, but that condition can only
happen during unload of IPVS, because during normal operation there is at least
our global stats structure in the estimator list. The mod_timer() and
del_timer_sync() calls are actually initialization and cleanup code in
disguise. Let's make it explicit and move them to their own init and cleanup
function.

Signed-off-by: Sven Wegener <sven.wegener@stealer.net>
Signed-off-by: Simon Horman <horms@verge.net.au>

2 files changed, 17 insertions, 9 deletions

diff --git a/net/ipv4/ipvs/ip_vs_core.c b/net/ipv4/ipvs/ip_vs_core.c
index a7879eafc3b5..9fbf0a6d7392 100644
--- a/net/ipv4/ipvs/ip_vs_core.c
+++ b/net/ipv4/ipvs/ip_vs_core.c
@@ -1070,10 +1070,12 @@ static int __init ip_vs_init(void)
 {
         int ret;
 
+        ip_vs_estimator_init();
+
         ret = ip_vs_control_init();
         if (ret < 0) {
                 IP_VS_ERR("can't setup control.\n");
-                goto cleanup_nothing;
+                goto cleanup_estimator;
         }
 
         ip_vs_protocol_init();
@@ -1106,7 +1108,8 @@ static int __init ip_vs_init(void)
   cleanup_protocol:
         ip_vs_protocol_cleanup();
         ip_vs_control_cleanup();
-  cleanup_nothing:
+  cleanup_estimator:
+        ip_vs_estimator_cleanup();
         return ret;
 }
 
@@ -1117,6 +1120,7 @@ static void __exit ip_vs_cleanup(void)
         ip_vs_app_cleanup();
         ip_vs_protocol_cleanup();
         ip_vs_control_cleanup();
+        ip_vs_estimator_cleanup();
         IP_VS_INFO("ipvs unloaded.\n");
 }
 
diff --git a/net/ipv4/ipvs/ip_vs_est.c b/net/ipv4/ipvs/ip_vs_est.c
index 5a20f93bd7f9..4fb620ec2086 100644
--- a/net/ipv4/ipvs/ip_vs_est.c
+++ b/net/ipv4/ipvs/ip_vs_est.c
@@ -124,8 +124,6 @@ void ip_vs_new_estimator(struct ip_vs_stats *stats)
         est->outbps = stats->outbps<<5;
 
         spin_lock_bh(&est_lock);
-        if (list_empty(&est_list))
-                mod_timer(&est_timer, jiffies + 2 * HZ);
         list_add(&est->list, &est_list);
         spin_unlock_bh(&est_lock);
 }
@@ -136,11 +134,6 @@ void ip_vs_kill_estimator(struct ip_vs_stats *stats)
 
         spin_lock_bh(&est_lock);
         list_del(&est->list);
-        while (list_empty(&est_list) && try_to_del_timer_sync(&est_timer) < 0) {
-                spin_unlock_bh(&est_lock);
-                cpu_relax();
-                spin_lock_bh(&est_lock);
-        }
         spin_unlock_bh(&est_lock);
 }
 
@@ -160,3 +153,14 @@ void ip_vs_zero_estimator(struct ip_vs_stats *stats)
         est->inbps = 0;
         est->outbps = 0;
 }
+
+int __init ip_vs_estimator_init(void)
+{
+        mod_timer(&est_timer, jiffies + 2 * HZ);
+        return 0;
+}
+
+void ip_vs_estimator_cleanup(void)
+{
+        del_timer_sync(&est_timer);
+}