From 249e52e35580fcfe5dad53a7dcd7c1252788749c Mon Sep 17 00:00:00 2001 From: Babu Moger Date: Wed, 14 Dec 2016 15:06:21 -0800 Subject: [PATCH] kernel/watchdog.c: move shared definitions to nmi.h Patch series "Clean up watchdog handlers", v2. This is an attempt to cleanup watchdog handlers. Right now, kernel/watchdog.c implements both softlockup and hardlockup detectors. Softlockup code is generic. Hardlockup code is arch specific. Some architectures don't use hardlockup detectors. They use their own watchdog detectors. To make both these combination work, we have numerous #ifdefs in kernel/watchdog.c. We are trying here to make these handlers independent of each other. Also provide an interface for architectures to implement their own handlers. watchdog_nmi_enable and watchdog_nmi_disable will be defined as weak such that architectures can override its definitions. Thanks to Don Zickus for his suggestions. Here are our previous discussions http://www.spinics.net/lists/sparclinux/msg16543.html http://www.spinics.net/lists/sparclinux/msg16441.html This patch (of 3): Move shared macros and definitions to nmi.h so that watchdog.c, new file watchdog_hld.c or any other architecture specific handler can use those definitions. Link: http://lkml.kernel.org/r/1478034826-43888-2-git-send-email-babu.moger@oracle.com Signed-off-by: Babu Moger Acked-by: Don Zickus Cc: Ingo Molnar Cc: Jiri Kosina Cc: Andi Kleen Cc: Yaowei Bai Cc: Aaron Tomlin Cc: Ulrich Obergfell Cc: Tejun Heo Cc: Hidehiro Kawai Cc: Josh Hunt Cc: "David S. Miller" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/nmi.h | 24 ++++++++++++++++++++++++ kernel/watchdog.c | 28 ++++------------------------ 2 files changed, 28 insertions(+), 24 deletions(-) diff --git a/include/linux/nmi.h b/include/linux/nmi.h index a78c35cff1ae..aacca824a6ae 100644 --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -7,6 +7,23 @@ #include #include +/* + * The run state of the lockup detectors is controlled by the content of the + * 'watchdog_enabled' variable. Each lockup detector has its dedicated bit - + * bit 0 for the hard lockup detector and bit 1 for the soft lockup detector. + * + * 'watchdog_user_enabled', 'nmi_watchdog_enabled' and 'soft_watchdog_enabled' + * are variables that are only used as an 'interface' between the parameters + * in /proc/sys/kernel and the internal state bits in 'watchdog_enabled'. The + * 'watchdog_thresh' variable is handled differently because its value is not + * boolean, and the lockup detectors are 'suspended' while 'watchdog_thresh' + * is equal zero. + */ +#define NMI_WATCHDOG_ENABLED_BIT 0 +#define SOFT_WATCHDOG_ENABLED_BIT 1 +#define NMI_WATCHDOG_ENABLED (1 << NMI_WATCHDOG_ENABLED_BIT) +#define SOFT_WATCHDOG_ENABLED (1 << SOFT_WATCHDOG_ENABLED_BIT) + /** * touch_nmi_watchdog - restart NMI watchdog timeout. * @@ -91,9 +108,16 @@ extern int nmi_watchdog_enabled; extern int soft_watchdog_enabled; extern int watchdog_user_enabled; extern int watchdog_thresh; +extern unsigned long watchdog_enabled; extern unsigned long *watchdog_cpumask_bits; +#ifdef CONFIG_SMP extern int sysctl_softlockup_all_cpu_backtrace; extern int sysctl_hardlockup_all_cpu_backtrace; +#else +#define sysctl_softlockup_all_cpu_backtrace 0 +#define sysctl_hardlockup_all_cpu_backtrace 0 +#endif +extern bool is_hardlockup(void); struct ctl_table; extern int proc_watchdog(struct ctl_table *, int , void __user *, size_t *, loff_t *); diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 6d1020c03d41..d21049496e26 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -27,29 +27,12 @@ #include #include -/* - * The run state of the lockup detectors is controlled by the content of the - * 'watchdog_enabled' variable. Each lockup detector has its dedicated bit - - * bit 0 for the hard lockup detector and bit 1 for the soft lockup detector. - * - * 'watchdog_user_enabled', 'nmi_watchdog_enabled' and 'soft_watchdog_enabled' - * are variables that are only used as an 'interface' between the parameters - * in /proc/sys/kernel and the internal state bits in 'watchdog_enabled'. The - * 'watchdog_thresh' variable is handled differently because its value is not - * boolean, and the lockup detectors are 'suspended' while 'watchdog_thresh' - * is equal zero. - */ -#define NMI_WATCHDOG_ENABLED_BIT 0 -#define SOFT_WATCHDOG_ENABLED_BIT 1 -#define NMI_WATCHDOG_ENABLED (1 << NMI_WATCHDOG_ENABLED_BIT) -#define SOFT_WATCHDOG_ENABLED (1 << SOFT_WATCHDOG_ENABLED_BIT) - static DEFINE_MUTEX(watchdog_proc_mutex); -#ifdef CONFIG_HARDLOCKUP_DETECTOR -static unsigned long __read_mostly watchdog_enabled = SOFT_WATCHDOG_ENABLED|NMI_WATCHDOG_ENABLED; +#if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR) +unsigned long __read_mostly watchdog_enabled = SOFT_WATCHDOG_ENABLED|NMI_WATCHDOG_ENABLED; #else -static unsigned long __read_mostly watchdog_enabled = SOFT_WATCHDOG_ENABLED; +unsigned long __read_mostly watchdog_enabled = SOFT_WATCHDOG_ENABLED; #endif int __read_mostly nmi_watchdog_enabled; int __read_mostly soft_watchdog_enabled; @@ -59,9 +42,6 @@ int __read_mostly watchdog_thresh = 10; #ifdef CONFIG_SMP int __read_mostly sysctl_softlockup_all_cpu_backtrace; int __read_mostly sysctl_hardlockup_all_cpu_backtrace; -#else -#define sysctl_softlockup_all_cpu_backtrace 0 -#define sysctl_hardlockup_all_cpu_backtrace 0 #endif static struct cpumask watchdog_cpumask __read_mostly; unsigned long *watchdog_cpumask_bits = cpumask_bits(&watchdog_cpumask); @@ -289,7 +269,7 @@ void touch_softlockup_watchdog_sync(void) #ifdef CONFIG_HARDLOCKUP_DETECTOR /* watchdog detector functions */ -static bool is_hardlockup(void) +bool is_hardlockup(void) { unsigned long hrint = __this_cpu_read(hrtimer_interrupts); -- GitLab