There is no need to keep NMI_DISABLED definition and use it for nmi_watchdog by default. Here is the point why: - IO-APIC and APIC chips are programmed for nmi_watchdog support at very early stage of kernel booting and not having nmi_watchdog specified as boot option lead only to nmi_watchdog becomes to NMI_NONE anyway - enable nmi_watchdog thru /proc/sys/kernel/nmi if it was not specified at boot is not possible too (even having this sysfs entry) Signed-off-by: Cyrill Gorcunov --- Index: linux-2.6.git/include/asm-x86/nmi.h ==================================================================== --- linux-2.6.git.orig/include/asm-x86/nmi.h 2008-06-24 19:30:34.000000000 +0400 +++ linux-2.6.git/include/asm-x86/nmi.h 2008-06-24 19:32:44.000000000 +0400 @@ -20,7 +20,6 @@ extern void default_do_nmi(struct pt_reg #endif extern void die_nmi(char *str, struct pt_regs *regs, int do_panic); -extern void nmi_watchdog_default(void); extern int check_nmi_watchdog(void); extern int nmi_watchdog_enabled; extern int avail_to_resrv_perfctr_nmi_bit(unsigned int); @@ -38,12 +37,10 @@ extern int nmi_watchdog_tick(struct pt_r extern atomic_t nmi_active; extern unsigned int nmi_watchdog; -#define NMI_DISABLED -1 #define NMI_NONE 0 #define NMI_IO_APIC 1 #define NMI_LOCAL_APIC 2 #define NMI_INVALID 3 -#define NMI_DEFAULT NMI_DISABLED struct ctl_table; struct file; Index: linux-2.6.git/arch/x86/kernel/apic_64.c ==================================================================== --- linux-2.6.git.orig/arch/x86/kernel/apic_64.c 2008-06-24 19:30:59.000000000 +0400 +++ linux-2.6.git/arch/x86/kernel/apic_64.c 2008-06-24 19:31:03.000000000 +0400 @@ -826,7 +826,6 @@ static void __cpuinit lapic_setup_esr(vo void __cpuinit end_local_APIC_setup(void) { lapic_setup_esr(); - nmi_watchdog_default(); setup_apic_nmi_watchdog(NULL); apic_pm_activate(); } Index: linux-2.6.git/arch/x86/kernel/io_apic_64.c ==================================================================== --- linux-2.6.git.orig/arch/x86/kernel/io_apic_64.c 2008-06-24 19:30:34.000000000 +0400 +++ linux-2.6.git/arch/x86/kernel/io_apic_64.c 2008-06-24 19:31:03.000000000 +0400 @@ -1729,7 +1729,6 @@ static inline void __init check_timer(vo } unmask_IO_APIC_irq(0); if (!no_timer_check && timer_irq_works()) { - nmi_watchdog_default(); if (nmi_watchdog == NMI_IO_APIC) { setup_nmi(); enable_8259A_irq(0); @@ -1758,7 +1757,6 @@ static inline void __init check_timer(vo if (timer_irq_works()) { apic_printk(APIC_VERBOSE," works.\n"); timer_through_8259 = 1; - nmi_watchdog_default(); if (nmi_watchdog == NMI_IO_APIC) { disable_8259A_irq(0); setup_nmi(); Index: linux-2.6.git/arch/x86/kernel/smpboot.c ==================================================================== --- linux-2.6.git.orig/arch/x86/kernel/smpboot.c 2008-06-24 19:30:34.000000000 +0400 +++ linux-2.6.git/arch/x86/kernel/smpboot.c 2008-06-24 19:31:03.000000000 +0400 @@ -1140,7 +1140,6 @@ static void __init smp_cpu_index_default void __init native_smp_prepare_cpus(unsigned int max_cpus) { preempt_disable(); - nmi_watchdog_default(); smp_cpu_index_default(); current_cpu_data = boot_cpu_data; cpu_callin_map = cpumask_of_cpu(0); Index: linux-2.6.git/arch/x86/kernel/nmi.c ==================================================================== --- linux-2.6.git.orig/arch/x86/kernel/nmi.c 2008-06-24 19:31:01.000000000 +0400 +++ linux-2.6.git/arch/x86/kernel/nmi.c 2008-06-24 19:32:09.000000000 +0400 @@ -49,7 +49,7 @@ static cpumask_t backtrace_mask = CPU_MA atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ EXPORT_SYMBOL(nmi_active); -unsigned int nmi_watchdog = NMI_DEFAULT; +unsigned int nmi_watchdog = NMI_NONE; EXPORT_SYMBOL(nmi_watchdog); static int panic_on_timeout; @@ -89,14 +89,6 @@ static inline unsigned int get_timer_irq #endif } -/* Run after command line and cpu_init init, but before all other checks */ -void nmi_watchdog_default(void) -{ - if (nmi_watchdog != NMI_DEFAULT) - return; - nmi_watchdog = NMI_NONE; -} - #ifdef CONFIG_SMP /* * The performance counters used by NMI_LOCAL_APIC don't trigger when @@ -124,7 +116,7 @@ int __init check_nmi_watchdog(void) unsigned int *prev_nmi_count; int cpu; - if (nmi_watchdog == NMI_NONE || nmi_watchdog == NMI_DISABLED) + if (nmi_watchdog == NMI_NONE) return 0; if (!atomic_read(&nmi_active)) @@ -481,24 +473,12 @@ int proc_nmi_enabled(struct ctl_table *t if (!!old_state == !!nmi_watchdog_enabled) return 0; - if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_DISABLED) { + if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_NONE) { printk(KERN_WARNING "NMI watchdog is permanently disabled\n"); return -EIO; } - /* if nmi_watchdog is not set yet, then set it */ - nmi_watchdog_default(); - -#ifdef CONFIG_X86_32 - if (nmi_watchdog == NMI_NONE) { - if (lapic_watchdog_ok()) - nmi_watchdog = NMI_LOCAL_APIC; - else - nmi_watchdog = NMI_IO_APIC; - } -#endif - if (nmi_watchdog == NMI_LOCAL_APIC) { if (nmi_watchdog_enabled) enable_lapic_nmi_watchdog(); -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/