Module Name: src
Committed By: hannken
Date: Tue Jun 11 09:05:33 UTC 2019
Modified Files:
src/external/cddl/osnet/sys/kern: taskq.c
Log Message:
There is no 1:1 relation between cv_signal() and cv_timedwait() as
the latter implicitly calls cv_signal() on error.
This leads to "tq_waiting > 0" with "tq_running == 0" and the
taskq stalls.
Change task_executor() to increment and decrement "tq_waiting"
and always check and run the queue after cv_timedwait().
Use mstohz(), fix timeout and sort includes.
Addresses PR port-xen/54273: "zpool create pool xbd2" panics DOMU kernel
To generate a diff of this commit:
cvs rdiff -u -r1.9 -r1.10 src/external/cddl/osnet/sys/kern/taskq.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/external/cddl/osnet/sys/kern/taskq.c
diff -u src/external/cddl/osnet/sys/kern/taskq.c:1.9 src/external/cddl/osnet/sys/kern/taskq.c:1.10
--- src/external/cddl/osnet/sys/kern/taskq.c:1.9 Tue May 7 08:49:59 2019
+++ src/external/cddl/osnet/sys/kern/taskq.c Tue Jun 11 09:05:33 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: taskq.c,v 1.9 2019/05/07 08:49:59 hannken Exp $ */
+/* $NetBSD: taskq.c,v 1.10 2019/06/11 09:05:33 hannken Exp $ */
/*-
* Copyright (c) 2019 The NetBSD Foundation, Inc.
@@ -30,9 +30,11 @@
*/
#include <sys/types.h>
-#include <sys/mutex.h>
+#include <sys/param.h>
#include <sys/kcondvar.h>
+#include <sys/kernel.h>
#include <sys/kmem.h>
+#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/threadpool.h>
@@ -65,7 +67,7 @@ static specificdata_key_t taskq_lwp_key;
/*
* Threadpool job to service tasks from task queue.
- * Runs until the task queue gets destroyed or the queue is empty for 5 secs.
+ * Runs until the task queue gets destroyed or the queue is empty for 10 secs.
*/
static void
task_executor(struct threadpool_job *job)
@@ -73,22 +75,27 @@ task_executor(struct threadpool_job *job
struct taskq_executor *state = (struct taskq_executor *)job;
taskq_t *tq = state->te_self;
taskq_ent_t *tqe;
+ int error;
lwp_setspecific(taskq_lwp_key, tq);
mutex_enter(&tq->tq_lock);
while (!tq->tq_destroyed) {
- tqe = SIMPLEQ_FIRST(&tq->tq_list);
- if (tqe == NULL) {
+ if (SIMPLEQ_EMPTY(&tq->tq_list)) {
if (ISSET(tq->tq_flags, TASKQ_DYNAMIC))
break;
tq->tq_waiting++;
- if (cv_timedwait(&tq->tq_cv, &tq->tq_lock, 5000) != 0) {
- tq->tq_waiting--;
- break;
+ error = cv_timedwait(&tq->tq_cv, &tq->tq_lock,
+ mstohz(10000));
+ tq->tq_waiting--;
+ if (SIMPLEQ_EMPTY(&tq->tq_list)) {
+ if (error)
+ break;
+ continue;
}
- continue;
}
+ tqe = SIMPLEQ_FIRST(&tq->tq_list);
+ KASSERT(tqe != NULL);
SIMPLEQ_REMOVE_HEAD(&tq->tq_list, tqent_list);
tqe->tqent_queued = 0;
mutex_exit(&tq->tq_lock);
@@ -144,7 +151,6 @@ taskq_dispatch_common(taskq_t *tq, taskq
tq->tq_active++;
if (tq->tq_waiting) {
cv_signal(&tq->tq_cv);
- tq->tq_waiting--;
mutex_exit(&tq->tq_lock);
return;
}
