From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Date: Mon, 9 Mar 2020 21:02:30 +0000 (+0100)
Subject: udev: add debug logs for delaying and delegation of events
X-Git-Tag: v246-rc1~766
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7600dbb870d3f8adc4e91ea35e93b44e5912e013;p=thirdparty%2Fsystemd.git

udev: add debug logs for delaying and delegation of events

Up to now each uevent logs the following things at debug level:

 - Device is queued
 - Processing device
 - Device processed

However when the device is queued it might still have to wait for
earlier devices to be processed before being able to start being
processed itself. When analysing logs this dependency information is
quite cruicial, so add respective debug log calls.
---

diff --git a/src/udev/udevd.c b/src/udev/udevd.c
index ca65474f276..456bc8c479a 100644
--- a/src/udev/udevd.c
+++ b/src/udev/udevd.c
@@ -559,6 +559,14 @@ static void event_run(Manager *manager, struct event *event) {
         assert(manager);
         assert(event);
 
+        if (DEBUG_LOGGING) {
+                DeviceAction action;
+
+                r = device_get_action(event->dev, &action);
+                log_device_debug(event->dev, "Device (SEQNUM=%"PRIu64", ACTION=%s) ready for processing",
+                                 event->seqnum, r >= 0 ? device_action_to_string(action) : "<unknown>");
+        }
+
         HASHMAP_FOREACH(worker, manager->workers, i) {
                 if (worker->state != WORKER_IDLE)
                         continue;
@@ -770,6 +778,9 @@ static int is_device_busy(Manager *manager, struct event *event) {
         return false;
 
 set_delaying_seqnum:
+        log_device_debug(event->dev, "SEQNUM=%" PRIu64 " blocked by SEQNUM=%" PRIu64,
+                         event->seqnum, loop_event->seqnum);
+
         event->delaying_seqnum = loop_event->seqnum;
         return true;
 }