nmi_watchdog: add asm/nmi.h for ARM64

hulk inclusion
category: bugfix
bugzilla: 16572
CVE: NA

-------------------------------------------------

When I compile the kernel with CONFIG_SDEI_WATCHDOG chosen and without
CONFIG_HARDLOCKUP_DETECTOR, I got the following error.
./include/linux/nmi.h: In function 'touch_nmi_watchdog':
./include/linux/nmi.h:141:2: error: implicit declaration of function 'arch_touch_nmi_watchdog' [-Werror=implicit-function-declaration]
  arch_touch_nmi_watchdog();
  ^~~~~~~~~~~~~~~~~~~~~~~

It is because CONFIG_SDEI_WATCHDOG selects HAVE_NMI_WATCHDOG, but we
didn't provide arch_touch_nmi_watchdog for ARM64 in 'asm/nmi.h'. This
patch implements arch_touch_nmi_watchdog() for ARM64 when
CONFIG_HARDLOCKUP_DETECTOR is not chosen.
Signed-off-by: NXiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

arch/arm64/include/asm/nmi.h

+/* SPDX-License-Identifier: GPL-2.0 */
+
+#if !defined(CONFIG_HARDLOCKUP_DETECTOR)
+static inline void arch_touch_nmi_watchdog(void) { }
+#endif

include/linux/nmi.h

@@ -7,7 +7,7 @@
 
 #include <linux/sched.h>
 #include <asm/irq.h>
-#if defined(CONFIG_HAVE_NMI_WATCHDOG) && !defined(CONFIG_SDEI_WATCHDOG)
+#if defined(CONFIG_HAVE_NMI_WATCHDOG)
 #include <asm/nmi.h>
 #endif
 
@@ -87,6 +87,7 @@ extern void watchdog_hardlockup_check(struct pt_regs *regs);
 extern unsigned int hardlockup_panic;
 #else
 static inline void hardlockup_detector_disable(void) {}
+static inline void watchdog_hardlockup_check(struct pt_regs *regs) {}
 #endif
 
 #if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR)