[PATCH] watchdog/softlockup: Fix SOFTLOCKUP_DETECTOR=n build

From: Peter Zijlstra
Date: Tue Jul 10 2018 - 07:42:33 EST


On Mon, Jul 09, 2018 at 11:40:14PM +0530, Abdul Haleem wrote:

> Thanks Peter for the patch, build and boot is fine.
>
> Reported-and-tested-by: Abdul Haleem <abdhalee@xxxxxxxxxxxxxxxxxx>

Excellent, Ingo can you stick this in?

---
Subject: watchdog/softlockup: Fix SOFTLOCKUP_DETECTOR=n build
From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Date: Mon, 9 Jul 2018 13:47:16 +0200

I got confused by all the various CONFIG options here about and
conflated CONFIG_LOCKUP_DETECTOR and CONFIG_SOFTLOCKUP_DETECTOR. This
results in a build failure for:

CONFIG_LOCKUP_DETECTOR=y && CONFIG_SOFTLOCKUP_DETECTOR=n

As reported by Abdul.

Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Cc: linuxppc-dev <linuxppc-dev@xxxxxxxxxxxxxxxx>
Cc: sachinp <sachinp@xxxxxxxxxxxxxxxxxx>
Cc: mpe <mpe@xxxxxxxxxxxxxx>
Reported-and-tested-by: Abdul Haleem <abdhalee@xxxxxxxxxxxxxxxxxx>
Fixes: 9cf57731b63e ("watchdog/softlockup: Replace "watchdog/%u" threads with cpu_stop_work")
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20180709114716.GN2476@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
---
include/linux/nmi.h | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)

--- a/include/linux/nmi.h
+++ b/include/linux/nmi.h
@@ -33,15 +33,10 @@ extern int sysctl_hardlockup_all_cpu_bac
#define sysctl_hardlockup_all_cpu_backtrace 0
#endif /* !CONFIG_SMP */

-extern int lockup_detector_online_cpu(unsigned int cpu);
-extern int lockup_detector_offline_cpu(unsigned int cpu);
-
#else /* CONFIG_LOCKUP_DETECTOR */
static inline void lockup_detector_init(void) { }
static inline void lockup_detector_soft_poweroff(void) { }
static inline void lockup_detector_cleanup(void) { }
-#define lockup_detector_online_cpu NULL
-#define lockup_detector_offline_cpu NULL
#endif /* !CONFIG_LOCKUP_DETECTOR */

#ifdef CONFIG_SOFTLOCKUP_DETECTOR
@@ -50,12 +45,18 @@ extern void touch_softlockup_watchdog(vo
extern void touch_softlockup_watchdog_sync(void);
extern void touch_all_softlockup_watchdogs(void);
extern unsigned int softlockup_panic;
-#else
+
+extern int lockup_detector_online_cpu(unsigned int cpu);
+extern int lockup_detector_offline_cpu(unsigned int cpu);
+#else /* CONFIG_SOFTLOCKUP_DETECTOR */
static inline void touch_softlockup_watchdog_sched(void) { }
static inline void touch_softlockup_watchdog(void) { }
static inline void touch_softlockup_watchdog_sync(void) { }
static inline void touch_all_softlockup_watchdogs(void) { }
-#endif
+
+#define lockup_detector_online_cpu NULL
+#define lockup_detector_offline_cpu NULL
+#endif /* CONFIG_SOFTLOCKUP_DETECTOR */

#ifdef CONFIG_DETECT_HUNG_TASK
void reset_hung_task_detector(void);