diff options
Diffstat (limited to 'arch/i386/kernel')
| -rw-r--r-- | arch/i386/kernel/apic.c | 78 | ||||
| -rw-r--r-- | arch/i386/kernel/time.c | 6 |
2 files changed, 82 insertions, 2 deletions
diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c index 2d8c6ce1ecd..acd3f1e34ca 100644 --- a/arch/i386/kernel/apic.c +++ b/arch/i386/kernel/apic.c @@ -26,6 +26,7 @@ #include <linux/kernel_stat.h> #include <linux/sysdev.h> #include <linux/cpu.h> +#include <linux/module.h> #include <asm/atomic.h> #include <asm/smp.h> @@ -37,10 +38,17 @@ #include <asm/i8253.h> #include <mach_apic.h> +#include <mach_ipi.h> #include "io_ports.h" /* + * cpu_mask that denotes the CPUs that needs timer interrupt coming in as + * IPIs in place of local APIC timers + */ +static cpumask_t timer_bcast_ipi; + +/* * Knob to control our willingness to enable the local APIC. */ int enable_local_apic __initdata = 0; /* -1=force-disable, +1=force-enable */ @@ -931,11 +939,16 @@ void (*wait_timer_tick)(void) __devinitdata = wait_8254_wraparound; static void __setup_APIC_LVTT(unsigned int clocks) { unsigned int lvtt_value, tmp_value, ver; + int cpu = smp_processor_id(); ver = GET_APIC_VERSION(apic_read(APIC_LVR)); lvtt_value = APIC_LVT_TIMER_PERIODIC | LOCAL_TIMER_VECTOR; if (!APIC_INTEGRATED(ver)) lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV); + + if (cpu_isset(cpu, timer_bcast_ipi)) + lvtt_value |= APIC_LVT_MASKED; + apic_write_around(APIC_LVTT, lvtt_value); /* @@ -1068,7 +1081,7 @@ void __devinit setup_secondary_APIC_clock(void) setup_APIC_timer(calibration_result); } -void __devinit disable_APIC_timer(void) +void disable_APIC_timer(void) { if (using_apic_timer) { unsigned long v; @@ -1080,7 +1093,10 @@ void __devinit disable_APIC_timer(void) void enable_APIC_timer(void) { - if (using_apic_timer) { + int cpu = smp_processor_id(); + + if (using_apic_timer && + !cpu_isset(cpu, timer_bcast_ipi)) { unsigned long v; v = apic_read(APIC_LVTT); @@ -1088,6 +1104,32 @@ void enable_APIC_timer(void) } } +void switch_APIC_timer_to_ipi(void *cpumask) +{ + cpumask_t mask = *(cpumask_t *)cpumask; + int cpu = smp_processor_id(); + + if (cpu_isset(cpu, mask) && + !cpu_isset(cpu, timer_bcast_ipi)) { + disable_APIC_timer(); + cpu_set(cpu, timer_bcast_ipi); + } +} +EXPORT_SYMBOL(switch_APIC_timer_to_ipi); + +void switch_ipi_to_APIC_timer(void *cpumask) +{ + cpumask_t mask = *(cpumask_t *)cpumask; + int cpu = smp_processor_id(); + + if (cpu_isset(cpu, mask) && + cpu_isset(cpu, timer_bcast_ipi)) { + cpu_clear(cpu, timer_bcast_ipi); + enable_APIC_timer(); + } +} +EXPORT_SYMBOL(switch_ipi_to_APIC_timer); + #undef APIC_DIVISOR /* @@ -1152,6 +1194,38 @@ fastcall void smp_apic_timer_interrupt(struct pt_regs *regs) irq_exit(); } +#ifndef CONFIG_SMP +static void up_apic_timer_interrupt_call(struct pt_regs *regs) +{ + int cpu = smp_processor_id(); + + /* + * the NMI deadlock-detector uses this. + */ + per_cpu(irq_stat, cpu).apic_timer_irqs++; + + smp_local_timer_interrupt(regs); +} +#endif + +void smp_send_timer_broadcast_ipi(struct pt_regs *regs) +{ + cpumask_t mask; + + cpus_and(mask, cpu_online_map, timer_bcast_ipi); + if (!cpus_empty(mask)) { +#ifdef CONFIG_SMP + send_IPI_mask(mask, LOCAL_TIMER_VECTOR); +#else + /* + * We can directly call the apic timer interrupt handler + * in UP case. Minus all irq related functions + */ + up_apic_timer_interrupt_call(regs); +#endif + } +} + int setup_profiling_timer(unsigned int multiplier) { return -EINVAL; diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c index 41c5b2dc620..a14d594bfbe 100644 --- a/arch/i386/kernel/time.c +++ b/arch/i386/kernel/time.c @@ -302,6 +302,12 @@ irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) do_timer_interrupt(irq, regs); write_sequnlock(&xtime_lock); + +#ifdef CONFIG_X86_LOCAL_APIC + if (using_apic_timer) + smp_send_timer_broadcast_ipi(regs); +#endif + return IRQ_HANDLED; } |