watchdog: introduce the hardlockup_detector_disable() function

Have kvm_guest_init() use hardlockup_detector_disable() instead of
watchdog_enable_hardlockup_detector(false).

Remove the watchdog_hardlockup_detector_is_enabled() and the
watchdog_enable_hardlockup_detector() function which are no longer needed.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 19 deletions

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 49d02250aaac..f2be11ab7e08 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -83,8 +83,6 @@ static unsigned long soft_lockup_nmi_warn;
 #ifdef CONFIG_HARDLOCKUP_DETECTOR
 static int hardlockup_panic =
                         CONFIG_BOOTPARAM_HARDLOCKUP_PANIC_VALUE;
-
-static bool hardlockup_detector_enabled = true;
 /*
  * We may not want to enable hard lockup detection by default in all cases,
  * for example when running the kernel as a guest on a hypervisor. In these
@@ -93,14 +91,9 @@ static bool hardlockup_detector_enabled = true;
  * kernel command line parameters are parsed, because otherwise it is not
  * possible to override this in hardlockup_panic_setup().
  */
-void watchdog_enable_hardlockup_detector(bool val)
-{
-        hardlockup_detector_enabled = val;
-}
-
-bool watchdog_hardlockup_detector_is_enabled(void)
+void hardlockup_detector_disable(void)
 {
-        return hardlockup_detector_enabled;
+        watchdog_enabled &= ~NMI_WATCHDOG_ENABLED;
 }
 
 static int __init hardlockup_panic_setup(char *str)
@@ -530,15 +523,6 @@ static int watchdog_nmi_enable(unsigned int cpu)
         if (!(watchdog_enabled & NMI_WATCHDOG_ENABLED))
                 goto out;
 
-        /*
-         * Some kernels need to default hard lockup detection to
-         * 'disabled', for example a guest on a hypervisor.
-         */
-        if (!watchdog_hardlockup_detector_is_enabled()) {
-                event = ERR_PTR(-ENOENT);
-                goto handle_err;
-        }
-
         /* is it already setup and enabled? */
         if (event && event->state > PERF_EVENT_STATE_OFF)
                 goto out;
@@ -553,7 +537,6 @@ static int watchdog_nmi_enable(unsigned int cpu)
         /* Try to register using hardware perf events */
         event = perf_event_create_kernel_counter(wd_attr, cpu, NULL, watchdog_overflow_callback, NULL);
 
-handle_err:
         /* save cpu0 error for future comparision */
         if (cpu == 0 && IS_ERR(event))
                 cpu0_err = PTR_ERR(event);