Implement set_perf_counter_pending() with a self-IPI so that it will
run ASAP in a usable context.
For now use a second IRQ vector, because the primary vector pokes
the apic in funny ways that seem to confuse things.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <
20090406094517.
724626696@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
#ifdef CONFIG_PERF_COUNTERS
BUILD_INTERRUPT(perf_counter_interrupt, LOCAL_PERF_VECTOR)
+BUILD_INTERRUPT(perf_pending_interrupt, LOCAL_PENDING_VECTOR)
#endif
#ifdef CONFIG_X86_MCE_P4THERMAL
#endif
unsigned int generic_irqs; /* arch dependent */
unsigned int apic_perf_irqs;
+ unsigned int apic_pending_irqs;
#ifdef CONFIG_SMP
unsigned int irq_resched_count;
unsigned int irq_call_count;
extern void generic_interrupt(void);
extern void error_interrupt(void);
extern void perf_counter_interrupt(void);
+extern void perf_pending_interrupt(void);
extern void spurious_interrupt(void);
extern void thermal_interrupt(void);
*/
#define GENERIC_INTERRUPT_VECTOR 0xed
+/*
+ * Performance monitoring pending work vector:
+ */
+#define LOCAL_PENDING_VECTOR 0xec
+
/*
* First APIC vector available to drivers: (vectors 0x30-0xee) we
* start at 0x31(0x41) to spread out vectors evenly between priority
#define MSR_ARCH_PERFMON_FIXED_CTR2 0x30b
#define X86_PMC_IDX_FIXED_BUS_CYCLES (X86_PMC_IDX_FIXED + 2)
-#define set_perf_counter_pending() do { } while (0)
+extern void set_perf_counter_pending(void);
+
#define clear_perf_counter_pending() do { } while (0)
#define test_perf_counter_pending() (0)
irq_exit();
}
+void smp_perf_pending_interrupt(struct pt_regs *regs)
+{
+ irq_enter();
+ ack_APIC_irq();
+ inc_irq_stat(apic_pending_irqs);
+ perf_counter_do_pending();
+ irq_exit();
+}
+
+void set_perf_counter_pending(void)
+{
+ apic->send_IPI_self(LOCAL_PENDING_VECTOR);
+}
+
void perf_counters_lapic_init(int nmi)
{
u32 apic_val;
#ifdef CONFIG_PERF_COUNTERS
apicinterrupt LOCAL_PERF_VECTOR \
perf_counter_interrupt smp_perf_counter_interrupt
+apicinterrupt LOCAL_PENDING_VECTOR \
+ perf_pending_interrupt smp_perf_pending_interrupt
#endif
/*
for_each_online_cpu(j)
seq_printf(p, "%10u ", irq_stats(j)->apic_perf_irqs);
seq_printf(p, " Performance counter interrupts\n");
+ seq_printf(p, "PND: ");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->apic_pending_irqs);
+ seq_printf(p, " Performance pending work\n");
#endif
if (generic_interrupt_extension) {
seq_printf(p, "PLT: ");
sum += irq_stats(cpu)->apic_timer_irqs;
sum += irq_stats(cpu)->irq_spurious_count;
sum += irq_stats(cpu)->apic_perf_irqs;
+ sum += irq_stats(cpu)->apic_pending_irqs;
#endif
if (generic_interrupt_extension)
sum += irq_stats(cpu)->generic_irqs;
alloc_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
# ifdef CONFIG_PERF_COUNTERS
alloc_intr_gate(LOCAL_PERF_VECTOR, perf_counter_interrupt);
+ alloc_intr_gate(LOCAL_PENDING_VECTOR, perf_pending_interrupt);
# endif
# ifdef CONFIG_X86_MCE_P4THERMAL
/* Performance monitoring interrupt: */
#ifdef CONFIG_PERF_COUNTERS
alloc_intr_gate(LOCAL_PERF_VECTOR, perf_counter_interrupt);
+ alloc_intr_gate(LOCAL_PENDING_VECTOR, perf_pending_interrupt);
#endif
}