26 files changed, 863 insertions, 377 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index d913e3b4bf0d..5368ba701de2 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2968,6 +2968,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                         Set maximum number of finished RCU callbacks to
                         process in one batch.
 
+        rcutree.gp_init_delay=  [KNL]
+                        Set the number of jiffies to delay each step of
+                        RCU grace-period initialization.  This only has
+                        effect when CONFIG_RCU_TORTURE_TEST_SLOW_INIT is
+                        set.
+
         rcutree.rcu_fanout_leaf= [KNL]
                         Increase the number of CPUs assigned to each
                         leaf rcu_node structure.  Useful for very large
diff --git a/arch/blackfin/mach-common/smp.c b/arch/blackfin/mach-common/smp.c
index 8ad3e90cc8fc..1c7259597395 100644
--- a/arch/blackfin/mach-common/smp.c
+++ b/arch/blackfin/mach-common/smp.c
@@ -413,16 +413,14 @@ int __cpu_disable(void)
         return 0;
 }
 
-static DECLARE_COMPLETION(cpu_killed);
-
 int __cpu_die(unsigned int cpu)
 {
-        return wait_for_completion_timeout(&cpu_killed, 5000);
+        return cpu_wait_death(cpu, 5);
 }
 
 void cpu_die(void)
 {
-        complete(&cpu_killed);
+        (void)cpu_report_death();
 
         atomic_dec(&init_mm.mm_users);
         atomic_dec(&init_mm.mm_count);
diff --git a/arch/metag/kernel/smp.c b/arch/metag/kernel/smp.c
index f006d2276f40..ac3a199e33e7 100644
--- a/arch/metag/kernel/smp.c
+++ b/arch/metag/kernel/smp.c
@@ -261,7 +261,6 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle)
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
-static DECLARE_COMPLETION(cpu_killed);
 
 /*
  * __cpu_disable runs on the processor to be shutdown.
@@ -299,7 +298,7 @@ int __cpu_disable(void)
  */
 void __cpu_die(unsigned int cpu)
 {
-        if (!wait_for_completion_timeout(&cpu_killed, msecs_to_jiffies(1)))
+        if (!cpu_wait_death(cpu, 1))
                 pr_err("CPU%u: unable to kill\n", cpu);
 }
 
@@ -314,7 +313,7 @@ void cpu_die(void)
         local_irq_disable();
         idle_task_exit();
 
-        complete(&cpu_killed);
+        (void)cpu_report_death();
 
         asm ("XOR       TXENABLE, D0Re0,D0Re0\n");
 }
diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index d2b12988d2ed..bf2caa1dedc5 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -34,8 +34,6 @@ extern int _debug_hotplug_cpu(int cpu, int action);
 #endif
 #endif
 
-DECLARE_PER_CPU(int, cpu_state);
-
 int mwait_usable(const struct cpuinfo_x86 *);
 
 #endif /* _ASM_X86_CPU_H */
diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h
index 8cd1cc3bc835..a5cb4f6e9492 100644
--- a/arch/x86/include/asm/smp.h
+++ b/arch/x86/include/asm/smp.h
@@ -150,12 +150,12 @@ static inline void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 }
 
 void cpu_disable_common(void);
-void cpu_die_common(unsigned int cpu);
 void native_smp_prepare_boot_cpu(void);
 void native_smp_prepare_cpus(unsigned int max_cpus);
 void native_smp_cpus_done(unsigned int max_cpus);
 int native_cpu_up(unsigned int cpunum, struct task_struct *tidle);
 int native_cpu_disable(void);
+int common_cpu_die(unsigned int cpu);
 void native_cpu_die(unsigned int cpu);
 void native_play_dead(void);
 void play_dead_common(void);
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index febc6aabc72e..c8fa34963ead 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -77,9 +77,6 @@
 #include <asm/realmode.h>
 #include <asm/misc.h>
 
-/* State of each CPU */
-DEFINE_PER_CPU(int, cpu_state) = { 0 };
-
 /* Number of siblings per CPU package */
 int smp_num_siblings = 1;
 EXPORT_SYMBOL(smp_num_siblings);
@@ -257,7 +254,7 @@ static void notrace start_secondary(void *unused)
         lock_vector_lock();
         set_cpu_online(smp_processor_id(), true);
         unlock_vector_lock();
-        per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
+        cpu_set_state_online(smp_processor_id());
         x86_platform.nmi_init();
 
         /* enable local interrupts */
@@ -948,7 +945,10 @@ int native_cpu_up(unsigned int cpu, struct task_struct *tidle)
          */
         mtrr_save_state();
 
-        per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
+        /* x86 CPUs take themselves offline, so delayed offline is OK. */
+        err = cpu_check_up_prepare(cpu);
+        if (err && err != -EBUSY)
+                return err;
 
         /* the FPU context is blank, nobody can own it */
         __cpu_disable_lazy_restore(cpu);
@@ -1191,7 +1191,7 @@ void __init native_smp_prepare_boot_cpu(void)
         switch_to_new_gdt(me);
         /* already set me in cpu_online_mask in boot_cpu_init() */
         cpumask_set_cpu(me, cpu_callout_mask);
-        per_cpu(cpu_state, me) = CPU_ONLINE;
+        cpu_set_state_online(me);
 }
 
 void __init native_smp_cpus_done(unsigned int max_cpus)
@@ -1318,14 +1318,10 @@ static void __ref remove_cpu_from_maps(int cpu)
         numa_remove_cpu(cpu);
 }
 
-static DEFINE_PER_CPU(struct completion, die_complete);
-
 void cpu_disable_common(void)
 {