hv_vmbus: Add gradually increased delay for retries in vmbus_post_msg()

[linux.git] / drivers / hv / connection.c

diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index a63a795300b9ebbec393154fdfdce27e38ad3b0c..b27220a425f4a44b6b1143f39017998f1b77533a 100644 (file)
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -216,10 +216,21 @@ int vmbus_connect(void)
 
 cleanup:
        pr_err("Unable to connect to host\n");
+
        vmbus_connection.conn_state = DISCONNECTED;
+       vmbus_disconnect();
+
+       kfree(msginfo);
 
-       if (vmbus_connection.work_queue)
+       return ret;
+}
+
+void vmbus_disconnect(void)
+{
+       if (vmbus_connection.work_queue) {
+               drain_workqueue(vmbus_connection.work_queue);
                destroy_workqueue(vmbus_connection.work_queue);
+       }
 
        if (vmbus_connection.int_page) {
                free_pages((unsigned long)vmbus_connection.int_page, 0);
@@ -230,10 +241,6 @@ int vmbus_connect(void)
        free_pages((unsigned long)vmbus_connection.monitor_pages[1], 0);
        vmbus_connection.monitor_pages[0] = NULL;
        vmbus_connection.monitor_pages[1] = NULL;
-
-       kfree(msginfo);
-
-       return ret;
 }
 
 /*
@@ -311,10 +318,8 @@ static void process_chn_event(u32 relid)
         */
        channel = pcpu_relid2channel(relid);
 
-       if (!channel) {
-               pr_err("channel not found for relid - %u\n", relid);
+       if (!channel)
                return;
-       }
 
        /*
         * A channel once created is persistent even when there
@@ -349,10 +354,7 @@ static void process_chn_event(u32 relid)
                        else
                                bytes_to_read = 0;
                } while (read_state && (bytes_to_read != 0));
-       } else {
-               pr_err("no channel callback for relid - %u\n", relid);
        }
-
 }
 
 /*
@@ -420,6 +422,7 @@ int vmbus_post_msg(void *buffer, size_t buflen)
        union hv_connection_id conn_id;
        int ret = 0;
        int retries = 0;
+       u32 msec = 1;
 
        conn_id.asu32 = 0;
        conn_id.u.id = VMBUS_MESSAGE_CONNECTION_ID;
@@ -429,13 +432,20 @@ int vmbus_post_msg(void *buffer, size_t buflen)
         * insufficient resources. Retry the operation a couple of
         * times before giving up.
         */
-       while (retries < 10) {
+       while (retries < 20) {
                ret = hv_post_message(conn_id, 1, buffer, buflen);
 
                switch (ret) {
+               case HV_STATUS_INVALID_CONNECTION_ID:
+                       /*
+                        * We could get this if we send messages too
+                        * frequently.
+                        */
+                       ret = -EAGAIN;
+                       break;
+               case HV_STATUS_INSUFFICIENT_MEMORY:
                case HV_STATUS_INSUFFICIENT_BUFFERS:
                        ret = -ENOMEM;
-               case -ENOMEM:
                        break;
                case HV_STATUS_SUCCESS:
                        return ret;
@@ -445,7 +455,9 @@ int vmbus_post_msg(void *buffer, size_t buflen)
                }
 
                retries++;
-               msleep(100);
+               msleep(msec);
+               if (msec < 2048)
+                       msec *= 2;
        }
        return ret;
 }