From a3d2f4261ef9a953904e3e21abafba0dad7daa77 Mon Sep 17 00:00:00 2001
From: gaoyi <gaoyi15@huawei.com>
Date: Mon, 28 Sep 2020 22:36:37 +0800
Subject: [PATCH] Retry to handle the uevent when worker is terminated abnormal

When processing uevent events fails, retry it.
---
 src/udev/udev-manager.c | 35 +++++++++++++++++++++++++++++++++--
 1 file changed, 33 insertions(+), 2 deletions(-)

diff --git a/src/udev/udev-manager.c b/src/udev/udev-manager.c
index 8077e51..88023c7 100644
--- a/src/udev/udev-manager.c
+++ b/src/udev/udev-manager.c
@@ -36,6 +36,7 @@
 #include "udev-worker.h"
 
 #define WORKER_NUM_MAX UINT64_C(2048)
+#define UEVENT_MAX_RETRY_TIMES 3
 
 #define EVENT_RETRY_INTERVAL_USEC (200 * USEC_PER_MSEC)
 #define EVENT_RETRY_TIMEOUT_USEC  (3 * USEC_PER_MINUTE)
@@ -50,6 +51,7 @@ typedef struct Event {
         Manager *manager;
         Worker *worker;
         EventState state;
+        int retry;
 
         sd_device *dev;
 
@@ -89,6 +91,32 @@ typedef struct Worker {
         Event *event;
 } Worker;
 
+static bool event_retry(Event *event) {
+        if (!event)
+                return false;
+
+        assert(event->manager);
+
+        if (--event->retry < 0) {
+                log_device_error(event->dev, "Retry failed.");
+                return false;
+        }
+
+        log_device_info(event->dev, "Retry %d times.", UEVENT_MAX_RETRY_TIMES - event->retry);
+
+        event->timeout_warning_event = sd_event_source_unref(event->timeout_warning_event);
+        event->timeout_event = sd_event_source_unref(event->timeout_event);
+
+        if (event->worker) {
+                event->worker->event = NULL;
+                event->worker = NULL;
+        }
+
+        event->state = EVENT_QUEUED;
+
+        return true;
+}
+
 static Event *event_free(Event *event) {
         if (!event)
                 return NULL;
@@ -735,6 +763,7 @@ static int event_queue_insert(Manager *manager, sd_device *dev) {
                 .devpath_old = devpath_old,
                 .devnode = devnode,
                 .state = EVENT_QUEUED,
+                .retry = UEVENT_MAX_RETRY_TIMES,
         };
 
         if (!manager->events) {
@@ -1126,8 +1155,10 @@ static int on_sigchld(sd_event_source *s, const siginfo_t *si, void *userdata) {
                 device_delete_db(dev);
                 device_tag_index(dev, NULL, false);
 
-                /* Forward kernel event to libudev listeners */
-                udev_broadcast_result(manager->monitor, dev, result);
+                if (event_retry(worker->event) == false) {
+                        /* Forward kernel event to libudev listeners */
+                        udev_broadcast_result(manager->monitor, dev, result);
+                }
         }
 
         worker_free(worker);
-- 
2.33.0

