Process-wide concurrency + Cancellation ownership fixes

src/proxy/client/authenticated.rs

@@ -155,18 +155,20 @@ impl RunningClientHandler {
             .or((config.access.user_max_tcp_conns_global_each > 0)
                 .then_some(config.access.user_max_tcp_conns_global_each))
             .map(|v| v as u64);
-        if !stats.try_acquire_user_curr_connects(user, limit) {
+        let Some(_connection_permit) = stats
+            .connection_authority()
+            .try_acquire(user, limit)
+        else {
             return Err(ProxyError::ConnectionLimitExceeded {
                 user: user.to_string(),
             });
-        }
+        };
 
         match ip_tracker.check_and_add(user, peer_addr.ip()).await {
             Ok(()) => {
                 ip_tracker.remove_ip(user, peer_addr.ip()).await;
             }
             Err(reason) => {
-                stats.decrement_user_curr_connects(user);
                 warn!(
                     user = %user,
                     ip = %peer_addr.ip(),
@@ -178,8 +180,6 @@ impl RunningClientHandler {
                 });
             }
         }
-
-        stats.decrement_user_curr_connects(user);
         Ok(())
     }
 }