[PATCH] i386: __send_IPI_dest_field - i386

Implement __send_IPI_dest_field which can be used to send IPIs when the
"destination shorthand" field of the ICR is set to 00 (destination
field). Use it whenever possible.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Andi Kleen <ak@suse.de>

1 files changed, 18 insertions, 29 deletions

diff --git a/arch/i386/kernel/smp.c b/arch/i386/kernel/smp.c
index 892cd64130bc..d14ffe2109b8 100644
--- a/arch/i386/kernel/smp.c
+++ b/arch/i386/kernel/smp.c
@@ -165,16 +165,13 @@ void fastcall send_IPI_self(int vector)
 }
 
 /*
- * This is only used on smaller machines.
+ * This is used to send an IPI with no shorthand notation (the destination is
+ * specified in bits 56 to 63 of the ICR).
  */
-void send_IPI_mask_bitmask(cpumask_t cpumask, int vector)
+static inline void __send_IPI_dest_field(unsigned long mask, int vector)
 {
-        unsigned long mask = cpus_addr(cpumask)[0];
         unsigned long cfg;
-        unsigned long flags;
 
-        local_irq_save(flags);
-        WARN_ON(mask & ~cpus_addr(cpu_online_map)[0]);
         /*
          * Wait for idle.
          */
@@ -195,13 +192,25 @@ void send_IPI_mask_bitmask(cpumask_t cpumask, int vector)
          * Send the IPI. The write to APIC_ICR fires this off.
          */
         apic_write_around(APIC_ICR, cfg);
+}
 
+/*
+ * This is only used on smaller machines.
+ */
+void send_IPI_mask_bitmask(cpumask_t cpumask, int vector)
+{
+        unsigned long mask = cpus_addr(cpumask)[0];
+        unsigned long flags;
+
+        local_irq_save(flags);
+        WARN_ON(mask & ~cpus_addr(cpu_online_map)[0]);
+        __send_IPI_dest_field(mask, vector);
         local_irq_restore(flags);
 }
 
 void send_IPI_mask_sequence(cpumask_t mask, int vector)
 {
-        unsigned long cfg, flags;
+        unsigned long flags;
         unsigned int query_cpu;
 
         /*
@@ -211,30 +220,10 @@ void send_IPI_mask_sequence(cpumask_t mask, int vector)
          */ 
 
         local_irq_save(flags);
-
         for (query_cpu = 0; query_cpu < NR_CPUS; ++query_cpu) {
                 if (cpu_isset(query_cpu, mask)) {
-                
-                        /*
-                         * Wait for idle.
-                         */
-                        apic_wait_icr_idle();
-                
-                        /*
-                         * prepare target chip field
-                         */
-                        cfg = __prepare_ICR2(cpu_to_logical_apicid(query_cpu));
-                        apic_write_around(APIC_ICR2, cfg);
-                
-                        /*
-                         * program the ICR 
-                         */
-                        cfg = __prepare_ICR(0, vector);
-                        
-                        /*
-                         * Send the IPI. The write to APIC_ICR fires this off.
-                         */
-                        apic_write_around(APIC_ICR, cfg);
+                        __send_IPI_dest_field(cpu_to_logical_apicid(query_cpu),
+                                              vector);
                 }
         }
         local_irq_restore(flags);