kernel: watchdog: modify the explanation related to watchdog thread

The watchdog thread has been replaced by cpu_stop_work, modify the
explanation related.

Link: https://lkml.kernel.org/r/1619687073-24686-2-git-send-email-wangqing@vivo.comSigned-off-by: NWang Qing <wangqing@vivo.com>
Reviewed-by: NPetr Mladek <pmladek@suse.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Stephen Kitt <steve@sk2.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: "Guilherme G. Piccoli" <gpiccoli@canonical.com>
Cc: Qais Yousef <qais.yousef@arm.com>
Cc: Santosh Sivaraj <santosh@fossix.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kernel/watchdog.c

@@ -92,7 +92,7 @@ __setup("nmi_watchdog=", hardlockup_panic_setup);
  * own hardlockup detector.
  *
  * watchdog_nmi_enable/disable can be implemented to start and stop when
- * softlockup watchdog threads start and stop. The arch must select the
+ * softlockup watchdog start and stop. The arch must select the
  * SOFTLOCKUP_DETECTOR Kconfig.
  */
 int __weak watchdog_nmi_enable(unsigned int cpu)
@@ -335,7 +335,7 @@ static DEFINE_PER_CPU(struct completion, softlockup_completion);
 static DEFINE_PER_CPU(struct cpu_stop_work, softlockup_stop_work);
 
 /*
- * The watchdog thread function - touches the timestamp.
+ * The watchdog feed function - touches the timestamp.
  *
  * It only runs once every sample_period seconds (4 seconds by
  * default) to reset the softlockup timestamp. If this gets delayed
@@ -558,11 +558,7 @@ static void lockup_detector_reconfigure(void)
 }
 
 /*
- * Create the watchdog thread infrastructure and configure the detector(s).
- *
- * The threads are not unparked as watchdog_allowed_mask is empty.  When
- * the threads are successfully initialized, take the proper locks and
- * unpark the threads in the watchdog_cpumask if the watchdog is enabled.
+ * Create the watchdog infrastructure and configure the detector(s).
  */
 static __init void lockup_detector_setup(void)
 {
@@ -628,7 +624,7 @@ void lockup_detector_soft_poweroff(void)
 
 #ifdef CONFIG_SYSCTL
 
-/* Propagate any changes to the watchdog threads */
+/* Propagate any changes to the watchdog infrastructure */
 static void proc_watchdog_update(void)
 {
 	/* Remove impossible cpus to keep sysctl output clean. */