[SPARC64]: dr-cpu unconfigure support.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 16 insertions, 5 deletions

diff --git a/arch/sparc64/kernel/process.c b/arch/sparc64/kernel/process.c
index f5f97e2c669c..93557507ec9f 100644
--- a/arch/sparc64/kernel/process.c
+++ b/arch/sparc64/kernel/process.c
@@ -29,6 +29,7 @@
 #include <linux/compat.h>
 #include <linux/tick.h>
 #include <linux/init.h>
+#include <linux/cpu.h>
 
 #include <asm/oplib.h>
 #include <asm/uaccess.h>
@@ -49,7 +50,7 @@
 
 /* #define VERBOSE_SHOWREGS */
 
-static void sparc64_yield(void)
+static void sparc64_yield(int cpu)
 {
         if (tlb_type != hypervisor)
                 return;
@@ -57,7 +58,7 @@ static void sparc64_yield(void)
         clear_thread_flag(TIF_POLLING_NRFLAG);
         smp_mb__after_clear_bit();
 
-        while (!need_resched()) {
+        while (!need_resched() && !cpu_is_offline(cpu)) {
                 unsigned long pstate;
 
                 /* Disable interrupts. */
@@ -68,7 +69,7 @@ static void sparc64_yield(void)
                         : "=&r" (pstate)
                         : "i" (PSTATE_IE));
 
-                if (!need_resched())
+                if (!need_resched() && !cpu_is_offline(cpu))
                         sun4v_cpu_yield();
 
                 /* Re-enable interrupts. */
@@ -86,15 +87,25 @@ static void sparc64_yield(void)
 /* The idle loop on sparc64. */
 void cpu_idle(void)
 {
+        int cpu = smp_processor_id();
+
         set_thread_flag(TIF_POLLING_NRFLAG);
 
         while(1) {
                 tick_nohz_stop_sched_tick();
-                while (!need_resched())
-                        sparc64_yield();
+
+                while (!need_resched() && !cpu_is_offline(cpu))
+                        sparc64_yield(cpu);
+
                 tick_nohz_restart_sched_tick();
 
                 preempt_enable_no_resched();
+
+#ifdef CONFIG_HOTPLUG_CPU
+                if (cpu_is_offline(cpu))
+                        cpu_play_dead();
+#endif
+
                 schedule();
                 preempt_disable();
         }