Log when starting and ending task exclusive mode

The task exclusive mode stops all processing (tasks and networking IO)
except the designated exclusive task events.  This has impact on the
operation of the server.  Add log messages indicating when we start the
exclusive mode, and when we end exclusive task mode.

diff --git a/lib/isc/task.c b/lib/isc/task.c
index d0f9d9be3843e1f0449f78ba056267ccb5cea095..666eb13fb2ac6e239d63eb347f52d9b3b3e28f4f 100644 (file)
--- a/lib/isc/task.c
+++ b/lib/isc/task.c
@@ -25,6 +25,7 @@
 #include <isc/atomic.h>
 #include <isc/condition.h>
 #include <isc/event.h>
+#include <isc/log.h>
 #include <isc/magic.h>
 #include <isc/mem.h>
 #include <isc/once.h>
@@ -1107,8 +1108,20 @@ isc_task_beginexclusive(isc_task_t *task) {
                return (ISC_R_LOCKBUSY);
        }
 
+       if (isc_log_wouldlog(isc_lctx, ISC_LOG_DEBUG(1))) {
+               isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
+                             ISC_LOGMODULE_OTHER, ISC_LOG_DEBUG(1),
+                             "exclusive task mode: %s", "starting");
+       }
+
        isc_nm_pause(manager->netmgr);
 
+       if (isc_log_wouldlog(isc_lctx, ISC_LOG_DEBUG(1))) {
+               isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
+                             ISC_LOGMODULE_OTHER, ISC_LOG_DEBUG(1),
+                             "exclusive task mode: %s", "started");
+       }
+
        return (ISC_R_SUCCESS);
 }
 
@@ -1120,7 +1133,20 @@ isc_task_endexclusive(isc_task_t *task) {
        REQUIRE(task->state == task_state_running);
        manager = task->manager;
 
+       if (isc_log_wouldlog(isc_lctx, ISC_LOG_DEBUG(1))) {
+               isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
+                             ISC_LOGMODULE_OTHER, ISC_LOG_DEBUG(1),
+                             "exclusive task mode: %s", "ending");
+       }
+
        isc_nm_resume(manager->netmgr);
+
+       if (isc_log_wouldlog(isc_lctx, ISC_LOG_DEBUG(1))) {
+               isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
+                             ISC_LOGMODULE_OTHER, ISC_LOG_DEBUG(1),
+                             "exclusive task mode: %s", "ended");
+       }
+
        REQUIRE(atomic_compare_exchange_strong(&manager->exclusive_req,
                                               &(bool){ true }, false));
 }