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-rw-r--r--arch/i386/kernel/apic.c131
1 files changed, 78 insertions, 53 deletions
diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c
index 496a2c9909f..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 */
@@ -92,10 +100,6 @@ void __init apic_intr_init(void)
/* Using APIC to generate smp_local_timer_interrupt? */
int using_apic_timer = 0;
-static DEFINE_PER_CPU(int, prof_multiplier) = 1;
-static DEFINE_PER_CPU(int, prof_old_multiplier) = 1;
-static DEFINE_PER_CPU(int, prof_counter) = 1;
-
static int enabled_via_apicbase;
void enable_NMI_through_LVT0 (void * dummy)
@@ -721,7 +725,7 @@ static int __init apic_set_verbosity(char *str)
apic_verbosity = APIC_VERBOSE;
else
printk(KERN_WARNING "APIC Verbosity level %s not recognised"
- " use apic=verbose or apic=debug", str);
+ " use apic=verbose or apic=debug\n", str);
return 0;
}
@@ -935,11 +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);
/*
@@ -1072,7 +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;
@@ -1084,7 +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);
@@ -1092,33 +1104,31 @@ void enable_APIC_timer(void)
}
}
-/*
- * the frequency of the profiling timer can be changed
- * by writing a multiplier value into /proc/profile.
- */
-int setup_profiling_timer(unsigned int multiplier)
+void switch_APIC_timer_to_ipi(void *cpumask)
{
- int i;
+ cpumask_t mask = *(cpumask_t *)cpumask;
+ int cpu = smp_processor_id();
- /*
- * Sanity check. [at least 500 APIC cycles should be
- * between APIC interrupts as a rule of thumb, to avoid
- * irqs flooding us]
- */
- if ( (!multiplier) || (calibration_result/multiplier < 500))
- return -EINVAL;
-
- /*
- * Set the new multiplier for each CPU. CPUs don't start using the
- * new values until the next timer interrupt in which they do process
- * accounting. At that time they also adjust their APIC timers
- * accordingly.
- */
- for (i = 0; i < NR_CPUS; ++i)
- per_cpu(prof_multiplier, i) = multiplier;
+ 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);
- return 0;
+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
@@ -1134,32 +1144,10 @@ int setup_profiling_timer(unsigned int multiplier)
inline void smp_local_timer_interrupt(struct pt_regs * regs)
{
- int cpu = smp_processor_id();
-
profile_tick(CPU_PROFILING, regs);
- if (--per_cpu(prof_counter, cpu) <= 0) {
- /*
- * The multiplier may have changed since the last time we got
- * to this point as a result of the user writing to
- * /proc/profile. In this case we need to adjust the APIC
- * timer accordingly.
- *
- * Interrupts are already masked off at this point.
- */
- per_cpu(prof_counter, cpu) = per_cpu(prof_multiplier, cpu);
- if (per_cpu(prof_counter, cpu) !=
- per_cpu(prof_old_multiplier, cpu)) {
- __setup_APIC_LVTT(
- calibration_result/
- per_cpu(prof_counter, cpu));
- per_cpu(prof_old_multiplier, cpu) =
- per_cpu(prof_counter, cpu);
- }
-
#ifdef CONFIG_SMP
- update_process_times(user_mode_vm(regs));
+ update_process_times(user_mode_vm(regs));
#endif
- }
/*
* We take the 'long' return path, and there every subsystem
@@ -1206,6 +1194,43 @@ 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;
+}
+
/*
* This interrupt should _never_ happen with our APIC/SMP architecture
*/