[src/trunk]: src/sys/external/bsd/common/linux No need to retry in cancel_del...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/043290ba3a94
branches:  trunk
changeset: 366354:043290ba3a94
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Mon Aug 27 15:02:19 2018 +0000

description:
No need to retry in cancel_delayed_work_sync after all.

diffstat:

 sys/external/bsd/common/linux/linux_work.c |  22 +++++++++-------------
 1 files changed, 9 insertions(+), 13 deletions(-)

diffs (59 lines):

diff -r 6e3b714ca0c8 -r 043290ba3a94 sys/external/bsd/common/linux/linux_work.c
--- a/sys/external/bsd/common/linux/linux_work.c        Mon Aug 27 15:02:08 2018 +0000
+++ b/sys/external/bsd/common/linux/linux_work.c        Mon Aug 27 15:02:19 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: linux_work.c,v 1.23 2018/08/27 15:02:08 riastradh Exp $        */
+/*     $NetBSD: linux_work.c,v 1.24 2018/08/27 15:02:19 riastradh Exp $        */
 
 /*-
  * Copyright (c) 2018 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: linux_work.c,v 1.23 2018/08/27 15:02:08 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: linux_work.c,v 1.24 2018/08/27 15:02:19 riastradh Exp $");
 
 #include <sys/types.h>
 #include <sys/atomic.h>
@@ -656,15 +656,11 @@
 cancel_delayed_work_sync(struct delayed_work *dw)
 {
        struct workqueue_struct *wq;
-       bool cancelled_p = false;
+       bool cancelled_p;
 
-retry:
-       /*
-        * If there's no workqueue, nothing to cancel, unless we've
-        * started over from cancelling the callout.
-        */
+       /* If there's no workqueue, nothing to cancel.  */
        if ((wq = dw->work.work_queue) == NULL)
-               return cancelled_p;
+               return false;
 
        mutex_enter(&wq->wq_lock);
        if (__predict_false(dw->work.work_queue != wq)) {
@@ -694,9 +690,9 @@
                         *
                         * If it's too late and the callout has already
                         * begun to execute, we must wait for it to
-                        * complete.  In that case, the work has been
-                        * dissociated from the queue, so we must start
-                        * over from the top.
+                        * complete.  But we got in soon enough to ask
+                        * the callout not to run, so we successfully
+                        * cancelled it in that case.
                         *
                         * If we stopped the callout before it started,
                         * however, then destroy the callout and
@@ -705,7 +701,7 @@
                        dw->dw_state = DELAYED_WORK_CANCELLED;
                        cancelled_p = true;
                        if (callout_halt(&dw->dw_callout, &wq->wq_lock))
-                               goto retry;
+                               break;
                        cancel_delayed_work_done(wq, dw);
                        break;
                default: