[IA64] Optional method to purge the TLB on SN systems

This patch adds an optional method for purging the TLB on SN IA64 systems.
The change should not affect any non-SN system.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 22 insertions, 5 deletions

diff --git a/arch/ia64/kernel/irq_ia64.c b/arch/ia64/kernel/irq_ia64.c
index 456f57b087ca..9a5f41be760b 100644
--- a/arch/ia64/kernel/irq_ia64.c
+++ b/arch/ia64/kernel/irq_ia64.c
@@ -39,6 +39,7 @@
 #include <asm/machvec.h>
 #include <asm/pgtable.h>
 #include <asm/system.h>
+#include <asm/tlbflush.h>
 
 #ifdef CONFIG_PERFMON
 # include <asm/perfmon.h>
@@ -127,8 +128,10 @@ void destroy_irq(unsigned int irq)
 
 #ifdef CONFIG_SMP
 #       define IS_RESCHEDULE(vec)       (vec == IA64_IPI_RESCHEDULE)
+#       define IS_LOCAL_TLB_FLUSH(vec)  (vec == IA64_IPI_LOCAL_TLB_FLUSH)
 #else
 #       define IS_RESCHEDULE(vec)       (0)
+#       define IS_LOCAL_TLB_FLUSH(vec)  (0)
 #endif
 /*
  * That's where the IVT branches when we get an external
@@ -180,8 +183,11 @@ ia64_handle_irq (ia64_vector vector, struct pt_regs *regs)
         saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
         ia64_srlz_d();
         while (vector != IA64_SPURIOUS_INT_VECTOR) {
-                if (unlikely(IS_RESCHEDULE(vector)))
-                         kstat_this_cpu.irqs[vector]++;
+                if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
+                        smp_local_flush_tlb();
+                        kstat_this_cpu.irqs[vector]++;
+                } else if (unlikely(IS_RESCHEDULE(vector)))
+                        kstat_this_cpu.irqs[vector]++;
                 else {
                         ia64_setreg(_IA64_REG_CR_TPR, vector);
                         ia64_srlz_d();
@@ -227,8 +233,11 @@ void ia64_process_pending_intr(void)
           * Perform normal interrupt style processing
           */
         while (vector != IA64_SPURIOUS_INT_VECTOR) {
-                if (unlikely(IS_RESCHEDULE(vector)))
-                         kstat_this_cpu.irqs[vector]++;
+                if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
+                        smp_local_flush_tlb();
+                        kstat_this_cpu.irqs[vector]++;
+                } else if (unlikely(IS_RESCHEDULE(vector)))
+                        kstat_this_cpu.irqs[vector]++;
                 else {
                         struct pt_regs *old_regs = set_irq_regs(NULL);
 
@@ -260,12 +269,12 @@ void ia64_process_pending_intr(void)
 
 
 #ifdef CONFIG_SMP
-extern irqreturn_t handle_IPI (int irq, void *dev_id);
 
 static irqreturn_t dummy_handler (int irq, void *dev_id)
 {
         BUG();
 }
+extern irqreturn_t handle_IPI (int irq, void *dev_id);
 
 static struct irqaction ipi_irqaction = {
         .handler =      handle_IPI,
@@ -278,6 +287,13 @@ static struct irqaction resched_irqaction = {
         .flags =        IRQF_DISABLED,
         .name =         "resched"
 };
+
+static struct irqaction tlb_irqaction = {
+        .handler =      dummy_handler,
+        .flags =        SA_INTERRUPT,
+        .name =         "tlb_flush"
+};
+
 #endif
 
 void
@@ -303,6 +319,7 @@ init_IRQ (void)
 #ifdef CONFIG_SMP
         register_percpu_irq(IA64_IPI_VECTOR, &ipi_irqaction);
         register_percpu_irq(IA64_IPI_RESCHEDULE, &resched_irqaction);
+        register_percpu_irq(IA64_IPI_LOCAL_TLB_FLUSH, &tlb_irqaction);
 #endif
 #ifdef CONFIG_PERFMON
         pfm_init_percpu();