PPC64: Generic hotplug cpu support

diff -u -p -B -r1.1.1.1 idle.c
@@ -293,6 +293,10 @@ static int native_idle(void)
 			power4_idle();
 		if (need_resched())
 			schedule();
+
+		if (cpu_is_offline(smp_processor_id()) &&
+		    system_state == SYSTEM_RUNNING)
+			cpu_die();
 	}
 	return 0;
 }

diff -u -p -B -r1.1.1.1 irq.c
@@ -115,6 +115,35 @@ skip:
 	return 0;
 }
 
+#ifdef CONFIG_HOTPLUG_CPU
+void fixup_irqs(cpumask_t map)
+{
+	unsigned int irq;
+	static int warned;
+
+	for_each_irq(irq) {
+		cpumask_t mask;
+
+		if (irq_desc[irq].status & IRQ_PER_CPU)
+			continue;
+
+		cpus_and(mask, irq_affinity[irq], map);
+		if (any_online_cpu(mask) == NR_CPUS) {
+			printk("Breaking affinity for irq %i\n", irq);
+			mask = map;
+		}
+		if (irq_desc[irq].handler->set_affinity)
+			irq_desc[irq].handler->set_affinity(irq, mask);
+		else if (irq_desc[irq].action && !(warned++))
+			printk("Cannot set affinity for irq %i\n", irq);
+	}
+
+	local_irq_enable();
+	mdelay(1);
+	local_irq_disable();
+}
+#endif
+
 extern int noirqdebug;
 
 /*

diff -u -p -B -r1.1.1.1 pSeries_setup.c
@@ -320,8 +320,9 @@ static  void __init pSeries_discover_pic
 	}
 }
 
-static void pSeries_cpu_die(void)
+static void pSeries_mach_cpu_die(void)
 {
+	idle_task_exit();
 	local_irq_disable();
 	/* Some hardware requires clearing the CPPR, while other hardware does not
 	 * it is safe either way

@@ -599,7 +600,7 @@ struct machdep_calls __initdata pSeries_
 	.power_off		= rtas_power_off,
 	.halt			= rtas_halt,
 	.panic			= rtas_os_term,
-	.cpu_die		= pSeries_cpu_die,
+	.cpu_die		= pSeries_mach_cpu_die,
 	.get_boot_time		= pSeries_get_boot_time,
 	.get_rtc_time		= pSeries_get_rtc_time,
 	.set_rtc_time		= pSeries_set_rtc_time,

diff -u -p -B -r1.1.1.1 pmac_setup.c
@@ -439,6 +439,9 @@ static int __init pmac_probe(int platfor
 }
 
 struct machdep_calls __initdata pmac_md = {
+#ifdef CONFIG_HOTPLUG_CPU
+	.cpu_die		= generic_mach_cpu_die,
+#endif
 	.probe			= pmac_probe,
 	.setup_arch		= pmac_setup_arch,
 	.init_early		= pmac_init_early,

diff -u -p -B -r1.1.1.1 pmac_smp.c
@@ -308,4 +308,9 @@ struct smp_ops_t core99_smp_ops __pmacda
 void __init pmac_setup_smp(void)
 {
 	smp_ops = &core99_smp_ops;
+#ifdef CONFIG_HOTPLUG_CPU
+	smp_ops->cpu_enable = generic_cpu_enable;
+	smp_ops->cpu_disable = generic_cpu_disable;
+	smp_ops->cpu_die = generic_cpu_die;
+#endif
 }

diff -u -p -B -r1.1.1.1 setup.c
@@ -1345,9 +1345,6 @@ early_param("xmon", early_xmon);
 
 void cpu_die(void)
 {
-	idle_task_exit();
 	if (ppc_md.cpu_die)
 		ppc_md.cpu_die();
-	local_irq_disable();
-	for (;;);
 }

96 lines not on this page · raw message

diff -u -p -B -r1.1.1.1 sysfs.c
@@ -18,7 +18,7 @@
 #include <asm/systemcfg.h>
 #include <asm/paca.h>
 #include <asm/lppaca.h>
-
+#include <asm/machdep.h>
 
 static DEFINE_PER_CPU(struct cpu, cpu_devices);
 

@@ -413,9 +413,7 @@ static int __init topology_init(void)
 		 * CPU.  For instance, the boot cpu might never be valid
 		 * for hotplugging.
 		 */
-#ifdef CONFIG_HOTPLUG_CPU
-		if (systemcfg->platform != PLATFORM_PSERIES_LPAR)
-#endif
+		if (!ppc_md.cpu_die)
 			c->no_control = 1;
 
 		if (cpu_online(cpu) || (c->no_control == 0)) {

diff -u -p -B -r1.1.1.1 machdep.h
@@ -30,6 +30,7 @@ struct smp_ops_t {
 	void  (*setup_cpu)(int nr);
 	void  (*take_timebase)(void);
 	void  (*give_timebase)(void);
+	int   (*cpu_enable)(unsigned int nr);
 	int   (*cpu_disable)(void);
 	void  (*cpu_die)(unsigned int nr);
 };

diff -u -p -B -r1.1.1.1 smp.h
@@ -29,7 +29,7 @@
 extern int boot_cpuid;
 extern int boot_cpuid_phys;
 
-extern void cpu_die(void) __attribute__((noreturn));
+extern void cpu_die(void);
 
 #ifdef CONFIG_SMP
 

@@ -37,6 +37,13 @@ extern void smp_send_debugger_break(int 
 struct pt_regs;
 extern void smp_message_recv(int, struct pt_regs *);
 
+#ifdef CONFIG_HOTPLUG_CPU
+extern void fixup_irqs(cpumask_t map);
+int generic_cpu_disable(void);
+int generic_cpu_enable(unsigned int cpu);
+void generic_cpu_die(unsigned int cpu);
+void generic_mach_cpu_die(void);
+#endif
 
 #define __smp_processor_id() (get_paca()->paca_index)
 #define hard_smp_processor_id() (get_paca()->hw_cpu_id)

@@ -294,7 +294,7 @@ static int native_idle(void)
 		if (need_resched())
 			schedule();
 
-		if (cpu_is_offline(smp_processor_id()) &&
+		if (cpu_is_offline(_smp_processor_id()) &&
 		    system_state == SYSTEM_RUNNING)
 			cpu_die();
 	}

Index: linux-2.6.11-rc5-mm1/init/main.c
===================================================================
@@ -638,6 +638,10 @@
 {
 	lock_kernel();
 	/*
+	 * init can run on any cpu.
+	 */
+	set_cpus_allowed(current, CPU_MASK_ALL);
+	/*
 	 * Tell the world that we're going to be the grim
 	 * reaper of innocent orphaned children.
 	 *

Index: linux-2.6.11-rc5-mm1/kernel/sched.c
===================================================================
@@ -4092,6 +4092,7 @@
 	idle->array = NULL;
 	idle->prio = MAX_PRIO;
 	idle->state = TASK_RUNNING;
+	idle->cpus_allowed = cpumask_of_cpu(cpu);
 	set_task_cpu(idle, cpu);
 
 	spin_lock_irqsave(&rq->lock, flags);