From 4de0043617f949fdac538fd59335e2150cd1b863 Mon Sep 17 00:00:00 2001 From: Cyrill Gorcunov Date: Tue, 24 Jun 2008 22:52:06 +0200 Subject: [PATCH] x86: nmi_watchdog - introduce nmi_watchdog_active() helper Signed-off-by: Cyrill Gorcunov Cc: macro@linux-mips.org Signed-off-by: Ingo Molnar --- arch/x86/kernel/nmi.c | 13 ++++--------- include/asm-x86/nmi.h | 13 +++++++++++++ 2 files changed, 17 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index 32acda2..8dfe9db 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -119,10 +119,7 @@ int __init check_nmi_watchdog(void) unsigned int *prev_nmi_count; int cpu; - if (nmi_watchdog == NMI_NONE) - return 0; - - if (!atomic_read(&nmi_active)) + if (!nmi_watchdog_active() || !atomic_read(&nmi_active)) return 0; prev_nmi_count = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL); @@ -317,8 +314,7 @@ void setup_apic_nmi_watchdog(void *unused) void stop_apic_nmi_watchdog(void *unused) { /* only support LOCAL and IO APICs for now */ - if (nmi_watchdog != NMI_LOCAL_APIC && - nmi_watchdog != NMI_IO_APIC) + if (!nmi_watchdog_active()) return; if (__get_cpu_var(wd_enabled) == 0) return; @@ -348,8 +344,7 @@ static DEFINE_PER_CPU(int, nmi_touch); void touch_nmi_watchdog(void) { - if (nmi_watchdog == NMI_LOCAL_APIC || - nmi_watchdog == NMI_IO_APIC) { + if (nmi_watchdog_active()) { unsigned cpu; /* @@ -474,7 +469,7 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, if (!!old_state == !!nmi_watchdog_enabled) return 0; - if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_NONE) { + if (atomic_read(&nmi_active) < 0 || !nmi_watchdog_active()) { printk(KERN_WARNING "NMI watchdog is permanently disabled\n"); return -EIO; diff --git a/include/asm-x86/nmi.h b/include/asm-x86/nmi.h index 1348e54..21f8d02 100644 --- a/include/asm-x86/nmi.h +++ b/include/asm-x86/nmi.h @@ -56,6 +56,19 @@ static inline void localise_nmi_watchdog(void) if (nmi_watchdog == NMI_IO_APIC) nmi_watchdog = NMI_LOCAL_APIC; } + +/* check if nmi_watchdog is active (ie was specified at boot) */ +static inline int nmi_watchdog_active(void) +{ + /* + * actually it should be: + * return (nmi_watchdog == NMI_LOCAL_APIC || + * nmi_watchdog == NMI_IO_APIC) + * but since they are power of two we could use a + * cheaper way --cvg + */ + return nmi_watchdog & 0x3; +} #endif void lapic_watchdog_stop(void); -- 2.7.4