1 files changed, 29 insertions, 0 deletions

diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
index 013e7eba83b..7539d84628f 100644
--- a/arch/x86/kernel/smp.c
+++ b/arch/x86/kernel/smp.c
@@ -23,6 +23,9 @@
 #include <linux/cpu.h>
 #include <linux/gfp.h>
 
+#include <litmus/preempt.h>
+#include <litmus/debug_trace.h>
+
 #include <asm/mtrr.h>
 #include <asm/tlbflush.h>
 #include <asm/mmu_context.h>
@@ -147,6 +150,16 @@ void native_send_call_func_ipi(const struct cpumask *mask)
         free_cpumask_var(allbutself);
 }
 
+/* trigger timers on remote cpu */
+void smp_send_pull_timers(int cpu)
+{
+        if (unlikely(cpu_is_offline(cpu))) {
+                WARN_ON(1);
+                return;
+        }
+        apic->send_IPI_mask(cpumask_of(cpu), PULL_TIMERS_VECTOR);
+}
+
 /*
  * this function calls the 'stop' function on all other CPUs in the system.
  */
@@ -204,6 +217,11 @@ void smp_reschedule_interrupt(struct pt_regs *regs)
         /*
          * KVM uses this interrupt to force a cpu out of guest mode
          */
+
+        /* LITMUS^RT: this IPI might need to trigger the sched state machine.
+         * Starting from 3.0 schedule_ipi() actually does something.  This may
+         * increase IPI latencies compared with previous versions. */
+        sched_state_ipi();
 }
 
 void smp_call_function_interrupt(struct pt_regs *regs)
@@ -224,6 +242,17 @@ void smp_call_function_single_interrupt(struct pt_regs *regs)
         irq_exit();
 }
 
+extern void hrtimer_pull(void);
+
+void smp_pull_timers_interrupt(struct pt_regs *regs)
+{
+        ack_APIC_irq();
+        irq_enter();
+        TRACE("pull timer interrupt\n");
+        hrtimer_pull();
+        irq_exit();
+}
+
 struct smp_ops smp_ops = {
         .smp_prepare_boot_cpu   = native_smp_prepare_boot_cpu,
         .smp_prepare_cpus       = native_smp_prepare_cpus,