[PATCH 1/5] Move rtas_stop_self() into platforms/pseries/hotplug-cpu.c

[PATCH 1/5] Move rtas_stop_self() into platforms/pseries/hotplug-cpu.c

[Michael Ellerman]

As the first step in consolidating the pseries hotplug cpu code,
create platforms/pseries/hotplug-cpu.c and move rtas_stop_self()
into it. Do the rtas token initialisation in a new initcall, rather
than rtas_initialize()

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
---

 arch/powerpc/kernel/rtas.c                   |   29 -------------
 arch/powerpc/platforms/pseries/Makefile      |    2 
 arch/powerpc/platforms/pseries/hotplug-cpu.c |   58 +++++++++++++++++++++++++++
 3 files changed, 60 insertions(+), 29 deletions(-)

Index: powerpc/arch/powerpc/kernel/rtas.c
===================================================================
--- powerpc.orig/arch/powerpc/kernel/rtas.c
+++ powerpc/arch/powerpc/kernel/rtas.c
@@ -810,32 +810,6 @@ asmlinkage int ppc_rtas(struct rtas_args
 	return 0;
 }
 
-#ifdef CONFIG_HOTPLUG_CPU
-/* This version can't take the spinlock, because it never returns */
-static struct rtas_args rtas_stop_self_args = {
-	/* The token is initialized for real in setup_system() */
-	.token = RTAS_UNKNOWN_SERVICE,
-	.nargs = 0,
-	.nret = 1,
-	.rets = &rtas_stop_self_args.args[0],
-};
-
-void rtas_stop_self(void)
-{
-	struct rtas_args *rtas_args = &rtas_stop_self_args;
-
-	local_irq_disable();
-
-	BUG_ON(rtas_args->token == RTAS_UNKNOWN_SERVICE);
-
-	printk("cpu %u (hwid %u) Ready to die...\n",
-	       smp_processor_id(), hard_smp_processor_id());
-	enter_rtas(__pa(rtas_args));
-
-	panic("Alas, I survived.\n");
-}
-#endif
-
 /*
  * Call early during boot, before mem init or bootmem, to retrieve the RTAS
  * informations from the device-tree and allocate the RMO buffer for userland
@@ -880,9 +854,6 @@ void __init rtas_initialize(void)
 #endif
 	rtas_rmo_buf = lmb_alloc_base(RTAS_RMOBUF_MAX, PAGE_SIZE, rtas_region);
 
-#ifdef CONFIG_HOTPLUG_CPU
-	rtas_stop_self_args.token = rtas_token("stop-self");
-#endif /* CONFIG_HOTPLUG_CPU */
 #ifdef CONFIG_RTAS_ERROR_LOGGING
 	rtas_last_error_token = rtas_token("rtas-last-error");
 #endif
Index: powerpc/arch/powerpc/platforms/pseries/Makefile
===================================================================
--- powerpc.orig/arch/powerpc/platforms/pseries/Makefile
+++ powerpc/arch/powerpc/platforms/pseries/Makefile
@@ -10,6 +10,8 @@ obj-$(CONFIG_XICS)	+= xics.o
 obj-$(CONFIG_SCANLOG)	+= scanlog.o
 obj-$(CONFIG_EEH)	+= eeh.o eeh_cache.o eeh_driver.o eeh_event.o
 
+obj-$(CONFIG_HOTPLUG_CPU)	+= hotplug-cpu.o
+
 obj-$(CONFIG_HVC_CONSOLE)	+= hvconsole.o
 obj-$(CONFIG_HVCS)		+= hvcserver.o
 obj-$(CONFIG_HCALL_STATS)	+= hvCall_inst.o
Index: powerpc/arch/powerpc/platforms/pseries/hotplug-cpu.c
===================================================================
--- /dev/null
+++ powerpc/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -0,0 +1,58 @@
+/*
+ * pseries CPU Hotplug infrastructure.
+ *
+ * Split out from arch/powerpc/kernel/rtas.c
+ *
+ * Peter Bergner, IBM	March 2001.
+ * Copyright (C) 2001 IBM.
+ *
+ * Copyright (C) 2006 Michael Ellerman, IBM Corporation
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/cpu.h>
+#include <asm/system.h>
+#include <asm/prom.h>
+#include <asm/rtas.h>
+#include <asm/firmware.h>
+#include <asm/machdep.h>
+#include <asm/vdso_datapage.h>
+#include <asm/pSeries_reconfig.h>
+#include "xics.h"
+
+/* This version can't take the spinlock, because it never returns */
+static struct rtas_args rtas_stop_self_args = {
+	.token = RTAS_UNKNOWN_SERVICE,
+	.nargs = 0,
+	.nret = 1,
+	.rets = &rtas_stop_self_args.args[0],
+};
+
+void rtas_stop_self(void)
+{
+	struct rtas_args *args = &rtas_stop_self_args;
+
+	local_irq_disable();
+
+	BUG_ON(args->token == RTAS_UNKNOWN_SERVICE);
+
+	printk("cpu %u (hwid %u) Ready to die...\n",
+	       smp_processor_id(), hard_smp_processor_id());
+	enter_rtas(__pa(args));
+
+	panic("Alas, I survived.\n");
+}
+
+static int __init pseries_cpu_hotplug_init(void)
+{
+	rtas_stop_self_args.token = rtas_token("stop-self");
+
+	return 0;
+}
+arch_initcall(pseries_cpu_hotplug_init);

[PATCH 2/5] Move pSeries_mach_cpu_die() into platforms/pseries/hotplug-cpu.c

[Michael Ellerman]

Move pSeries_mach_cpu_die() into platforms/pseries/hotplug-cpu.c,
this allows rtas_stop_self() to be static so remove the prototype.

Wire up pSeries_mach_cpu_die() in the initcall, rather than statically
in setup.c, the initcall will still run prior to the cpu hotplug code
being callable, so there should be no change in behaviour.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
---

 arch/powerpc/platforms/pseries/hotplug-cpu.c |   18 ++++++++++++++++--
 arch/powerpc/platforms/pseries/setup.c       |   16 ----------------
 include/asm-powerpc/rtas.h                   |    2 --
 3 files changed, 16 insertions(+), 20 deletions(-)

Index: powerpc/arch/powerpc/platforms/pseries/hotplug-cpu.c
===================================================================
--- powerpc.orig/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ powerpc/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -1,7 +1,8 @@
 /*
  * pseries CPU Hotplug infrastructure.
  *
- * Split out from arch/powerpc/kernel/rtas.c
+ * Split out from arch/powerpc/platforms/pseries/setup.c and
+ *  arch/powerpc/kernel/rtas.c
  *
  * Peter Bergner, IBM	March 2001.
  * Copyright (C) 2001 IBM.
@@ -34,7 +35,7 @@ static struct rtas_args rtas_stop_self_a
 	.rets = &rtas_stop_self_args.args[0],
 };
 
-void rtas_stop_self(void)
+static void rtas_stop_self(void)
 {
 	struct rtas_args *args = &rtas_stop_self_args;
 
@@ -49,10 +50,23 @@ void rtas_stop_self(void)
 	panic("Alas, I survived.\n");
 }
 
+static void pSeries_mach_cpu_die(void)
+{
+	local_irq_disable();
+	idle_task_exit();
+	xics_teardown_cpu(0);
+	rtas_stop_self();
+	/* Should never get here... */
+	BUG();
+	for(;;);
+}
+
 static int __init pseries_cpu_hotplug_init(void)
 {
 	rtas_stop_self_args.token = rtas_token("stop-self");
 
+	ppc_md.cpu_die = pSeries_mach_cpu_die;
+
 	return 0;
 }
 arch_initcall(pseries_cpu_hotplug_init);
Index: powerpc/arch/powerpc/platforms/pseries/setup.c
===================================================================
--- powerpc.orig/arch/powerpc/platforms/pseries/setup.c
+++ powerpc/arch/powerpc/platforms/pseries/setup.c
@@ -347,21 +347,6 @@ static int __init pSeries_init_panel(voi
 }
 arch_initcall(pSeries_init_panel);
 
-#ifdef CONFIG_HOTPLUG_CPU
-static void pSeries_mach_cpu_die(void)
-{
-	local_irq_disable();
-	idle_task_exit();
-	xics_teardown_cpu(0);
-	rtas_stop_self();
-	/* Should never get here... */
-	BUG();
-	for(;;);
-}
-#else
-#define pSeries_mach_cpu_die NULL
-#endif
-
 static int pseries_set_dabr(unsigned long dabr)
 {
 	return plpar_hcall_norets(H_SET_DABR, dabr);
@@ -561,7 +546,6 @@ define_machine(pseries) {
 	.power_off		= rtas_power_off,
 	.halt			= rtas_halt,
 	.panic			= rtas_os_term,
-	.cpu_die		= pSeries_mach_cpu_die,
 	.get_boot_time		= rtas_get_boot_time,
 	.get_rtc_time		= rtas_get_rtc_time,
 	.set_rtc_time		= rtas_set_rtc_time,
Index: powerpc/include/asm-powerpc/rtas.h
===================================================================
--- powerpc.orig/include/asm-powerpc/rtas.h
+++ powerpc/include/asm-powerpc/rtas.h
@@ -221,8 +221,6 @@ extern int rtas_get_error_log_max(void);
 extern spinlock_t rtas_data_buf_lock;
 extern char rtas_data_buf[RTAS_DATA_BUF_SIZE];
 
-extern void rtas_stop_self(void);
-
 /* RMO buffer reserved for user-space RTAS use */
 extern unsigned long rtas_rmo_buf;
 

[PATCH 3/5] Move the rest of the hotplug cpu code into platforms/pseries/hotplug-cpu.c

[Michael Ellerman]

Move the rest of the hotplug cpu code from platforms/pseries/smp.c into
platforms/pseries/hotplug-cpu.c.

Wire up the smp_ops callbacks and the notifier in the hotplug cpu initcall,
rather than in smp_init_pseries(). No change in behaviour.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
---

 arch/powerpc/platforms/pseries/hotplug-cpu.c |  201 ++++++++++++++++++++++++++-
 arch/powerpc/platforms/pseries/smp.c         |  200 --------------------------
 2 files changed, 199 insertions(+), 202 deletions(-)

Index: powerpc/arch/powerpc/platforms/pseries/hotplug-cpu.c
===================================================================
--- powerpc.orig/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ powerpc/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -1,11 +1,14 @@
 /*
  * pseries CPU Hotplug infrastructure.
  *
- * Split out from arch/powerpc/platforms/pseries/setup.c and
- *  arch/powerpc/kernel/rtas.c
+ * Split out from arch/powerpc/platforms/pseries/setup.c
+ *  arch/powerpc/kernel/rtas.c, and arch/powerpc/platforms/pseries/smp.c
  *
  * Peter Bergner, IBM	March 2001.
  * Copyright (C) 2001 IBM.
+ * Dave Engebretsen, Peter Bergner, and
+ * Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
+ * Plus various changes from other IBM teams...
  *
  * Copyright (C) 2006 Michael Ellerman, IBM Corporation
  *
@@ -61,12 +64,206 @@ static void pSeries_mach_cpu_die(void)
 	for(;;);
 }
 
+/* Get state of physical CPU.
+ * Return codes:
+ *	0	- The processor is in the RTAS stopped state
+ *	1	- stop-self is in progress
+ *	2	- The processor is not in the RTAS stopped state
+ *	-1	- Hardware Error
+ *	-2	- Hardware Busy, Try again later.
+ */
+static int query_cpu_stopped(unsigned int pcpu)
+{
+	int cpu_status;
+	int status, qcss_tok;
+
+	qcss_tok = rtas_token("query-cpu-stopped-state");
+	if (qcss_tok == RTAS_UNKNOWN_SERVICE)
+		return -1;
+	status = rtas_call(qcss_tok, 1, 2, &cpu_status, pcpu);
+	if (status != 0) {
+		printk(KERN_ERR
+		       "RTAS query-cpu-stopped-state failed: %i\n", status);
+		return status;
+	}
+
+	return cpu_status;
+}
+
+static int pSeries_cpu_disable(void)
+{
+	int cpu = smp_processor_id();
+
+	cpu_clear(cpu, cpu_online_map);
+	vdso_data->processorCount--;
+
+	/*fix boot_cpuid here*/
+	if (cpu == boot_cpuid)
+		boot_cpuid = any_online_cpu(cpu_online_map);
+
+	/* FIXME: abstract this to not be platform specific later on */
+	xics_migrate_irqs_away();
+	return 0;
+}
+
+static void pSeries_cpu_die(unsigned int cpu)
+{
+	int tries;
+	int cpu_status;
+	unsigned int pcpu = get_hard_smp_processor_id(cpu);
+
+	for (tries = 0; tries < 25; tries++) {
+		cpu_status = query_cpu_stopped(pcpu);
+		if (cpu_status == 0 || cpu_status == -1)
+			break;
+		msleep(200);
+	}
+	if (cpu_status != 0) {
+		printk("Querying DEAD? cpu %i (%i) shows %i\n",
+		       cpu, pcpu, cpu_status);
+	}
+
+	/* Isolation and deallocation are definatly done by
+	 * drslot_chrp_cpu.  If they were not they would be
+	 * done here.  Change isolate state to Isolate and
+	 * change allocation-state to Unusable.
+	 */
+	paca[cpu].cpu_start = 0;
+}
+
+/*
+ * Update cpu_present_map and paca(s) for a new cpu node.  The wrinkle
+ * here is that a cpu device node may represent up to two logical cpus
+ * in the SMT case.  We must honor the assumption in other code that
+ * the logical ids for sibling SMT threads x and y are adjacent, such
+ * that x^1 == y and y^1 == x.
+ */
+static int pSeries_add_processor(struct device_node *np)
+{
+	unsigned int cpu;
+	cpumask_t candidate_map, tmp = CPU_MASK_NONE;
+	int err = -ENOSPC, len, nthreads, i;
+	const u32 *intserv;
+
+	intserv = get_property(np, "ibm,ppc-interrupt-server#s", &len);
+	if (!intserv)
+		return 0;
+
+	nthreads = len / sizeof(u32);
+	for (i = 0; i < nthreads; i++)
+		cpu_set(i, tmp);
+
+	lock_cpu_hotplug();
+
+	BUG_ON(!cpus_subset(cpu_present_map, cpu_possible_map));
+
+	/* Get a bitmap of unoccupied slots. */
+	cpus_xor(candidate_map, cpu_possible_map, cpu_present_map);
+	if (cpus_empty(candidate_map)) {
+		/* If we get here, it most likely means that NR_CPUS is
+		 * less than the partition's max processors setting.
+		 */
+		printk(KERN_ERR "Cannot add cpu %s; this system configuration"
+		       " supports %d logical cpus.\n", np->full_name,
+		       cpus_weight(cpu_possible_map));
+		goto out_unlock;
+	}
+
+	while (!cpus_empty(tmp))
+		if (cpus_subset(tmp, candidate_map))
+			/* Found a range where we can insert the new cpu(s) */
+			break;
+		else
+			cpus_shift_left(tmp, tmp, nthreads);
+
+	if (cpus_empty(tmp)) {
+		printk(KERN_ERR "Unable to find space in cpu_present_map for"
+		       " processor %s with %d thread(s)\n", np->name,
+		       nthreads);
+		goto out_unlock;
+	}
+
+	for_each_cpu_mask(cpu, tmp) {
+		BUG_ON(cpu_isset(cpu, cpu_present_map));
+		cpu_set(cpu, cpu_present_map);
+		set_hard_smp_processor_id(cpu, *intserv++);
+	}
+	err = 0;
+out_unlock:
+	unlock_cpu_hotplug();
+	return err;
+}
+
+/*
+ * Update the present map for a cpu node which is going away, and set
+ * the hard id in the paca(s) to -1 to be consistent with boot time
+ * convention for non-present cpus.
+ */
+static void pSeries_remove_processor(struct device_node *np)
+{
+	unsigned int cpu;
+	int len, nthreads, i;
+	const u32 *intserv;
+
+	intserv = get_property(np, "ibm,ppc-interrupt-server#s", &len);
+	if (!intserv)
+		return;
+
+	nthreads = len / sizeof(u32);
+
+	lock_cpu_hotplug();
+	for (i = 0; i < nthreads; i++) {
+		for_each_present_cpu(cpu) {
+			if (get_hard_smp_processor_id(cpu) != intserv[i])
+				continue;
+			BUG_ON(cpu_online(cpu));
+			cpu_clear(cpu, cpu_present_map);
+			set_hard_smp_processor_id(cpu, -1);
+			break;
+		}
+		if (cpu == NR_CPUS)
+			printk(KERN_WARNING "Could not find cpu to remove "
+			       "with physical id 0x%x\n", intserv[i]);
+	}
+	unlock_cpu_hotplug();
+}
+
+static int pSeries_smp_notifier(struct notifier_block *nb, unsigned long action, void *node)
+{
+	int err = NOTIFY_OK;
+
+	switch (action) {
+	case PSERIES_RECONFIG_ADD:
+		if (pSeries_add_processor(node))
+			err = NOTIFY_BAD;
+		break;
+	case PSERIES_RECONFIG_REMOVE:
+		pSeries_remove_processor(node);
+		break;
+	default:
+		err = NOTIFY_DONE;
+		break;
+	}
+	return err;
+}
+
+static struct notifier_block pSeries_smp_nb = {
+	.notifier_call = pSeries_smp_notifier,
+};
+
 static int __init pseries_cpu_hotplug_init(void)
 {
 	rtas_stop_self_args.token = rtas_token("stop-self");
 
 	ppc_md.cpu_die = pSeries_mach_cpu_die;
 
+	smp_ops->cpu_disable = pSeries_cpu_disable;
+	smp_ops->cpu_die = pSeries_cpu_die;
+
+	/* Processors can be added/removed only on LPAR */
+	if (firmware_has_feature(FW_FEATURE_LPAR))
+		pSeries_reconfig_notifier_register(&pSeries_smp_nb);
+
 	return 0;
 }
 arch_initcall(pseries_cpu_hotplug_init);
Index: powerpc/arch/powerpc/platforms/pseries/smp.c
===================================================================
--- powerpc.orig/arch/powerpc/platforms/pseries/smp.c
+++ powerpc/arch/powerpc/platforms/pseries/smp.c
@@ -64,197 +64,6 @@ static cpumask_t of_spin_map;
 
 extern void generic_secondary_smp_init(unsigned long);
 
-#ifdef CONFIG_HOTPLUG_CPU
-
-/* Get state of physical CPU.
- * Return codes:
- *	0	- The processor is in the RTAS stopped state
- *	1	- stop-self is in progress
- *	2	- The processor is not in the RTAS stopped state
- *	-1	- Hardware Error
- *	-2	- Hardware Busy, Try again later.
- */
-static int query_cpu_stopped(unsigned int pcpu)
-{
-	int cpu_status;
-	int status, qcss_tok;
-
-	qcss_tok = rtas_token("query-cpu-stopped-state");
-	if (qcss_tok == RTAS_UNKNOWN_SERVICE)
-		return -1;
-	status = rtas_call(qcss_tok, 1, 2, &cpu_status, pcpu);
-	if (status != 0) {
-		printk(KERN_ERR
-		       "RTAS query-cpu-stopped-state failed: %i\n", status);
-		return status;
-	}
-
-	return cpu_status;
-}
-
-static int pSeries_cpu_disable(void)
-{
-	int cpu = smp_processor_id();
-
-	cpu_clear(cpu, cpu_online_map);
-	vdso_data->processorCount--;
-
-	/*fix boot_cpuid here*/
-	if (cpu == boot_cpuid)
-		boot_cpuid = any_online_cpu(cpu_online_map);
-
-	/* FIXME: abstract this to not be platform specific later on */
-	xics_migrate_irqs_away();
-	return 0;
-}
-
-static void pSeries_cpu_die(unsigned int cpu)
-{
-	int tries;
-	int cpu_status;
-	unsigned int pcpu = get_hard_smp_processor_id(cpu);
-
-	for (tries = 0; tries < 25; tries++) {
-		cpu_status = query_cpu_stopped(pcpu);
-		if (cpu_status == 0 || cpu_status == -1)
-			break;
-		msleep(200);
-	}
-	if (cpu_status != 0) {
-		printk("Querying DEAD? cpu %i (%i) shows %i\n",
-		       cpu, pcpu, cpu_status);
-	}
-
-	/* Isolation and deallocation are definatly done by
-	 * drslot_chrp_cpu.  If they were not they would be
-	 * done here.  Change isolate state to Isolate and
-	 * change allocation-state to Unusable.
-	 */
-	paca[cpu].cpu_start = 0;
-}
-
-/*
- * Update cpu_present_map and paca(s) for a new cpu node.  The wrinkle
- * here is that a cpu device node may represent up to two logical cpus
- * in the SMT case.  We must honor the assumption in other code that
- * the logical ids for sibling SMT threads x and y are adjacent, such
- * that x^1 == y and y^1 == x.
- */
-static int pSeries_add_processor(struct device_node *np)
-{
-	unsigned int cpu;
-	cpumask_t candidate_map, tmp = CPU_MASK_NONE;
-	int err = -ENOSPC, len, nthreads, i;
-	const u32 *intserv;
-
-	intserv = get_property(np, "ibm,ppc-interrupt-server#s", &len);
-	if (!intserv)
-		return 0;
-
-	nthreads = len / sizeof(u32);
-	for (i = 0; i < nthreads; i++)
-		cpu_set(i, tmp);
-
-	lock_cpu_hotplug();
-
-	BUG_ON(!cpus_subset(cpu_present_map, cpu_possible_map));
-
-	/* Get a bitmap of unoccupied slots. */
-	cpus_xor(candidate_map, cpu_possible_map, cpu_present_map);
-	if (cpus_empty(candidate_map)) {
-		/* If we get here, it most likely means that NR_CPUS is
-		 * less than the partition's max processors setting.
-		 */
-		printk(KERN_ERR "Cannot add cpu %s; this system configuration"
-		       " supports %d logical cpus.\n", np->full_name,
-		       cpus_weight(cpu_possible_map));
-		goto out_unlock;
-	}
-
-	while (!cpus_empty(tmp))
-		if (cpus_subset(tmp, candidate_map))
-			/* Found a range where we can insert the new cpu(s) */
-			break;
-		else
-			cpus_shift_left(tmp, tmp, nthreads);
-
-	if (cpus_empty(tmp)) {
-		printk(KERN_ERR "Unable to find space in cpu_present_map for"
-		       " processor %s with %d thread(s)\n", np->name,
-		       nthreads);
-		goto out_unlock;
-	}
-
-	for_each_cpu_mask(cpu, tmp) {
-		BUG_ON(cpu_isset(cpu, cpu_present_map));
-		cpu_set(cpu, cpu_present_map);
-		set_hard_smp_processor_id(cpu, *intserv++);
-	}
-	err = 0;
-out_unlock:
-	unlock_cpu_hotplug();
-	return err;
-}
-
-/*
- * Update the present map for a cpu node which is going away, and set
- * the hard id in the paca(s) to -1 to be consistent with boot time
- * convention for non-present cpus.
- */
-static void pSeries_remove_processor(struct device_node *np)
-{
-	unsigned int cpu;
-	int len, nthreads, i;
-	const u32 *intserv;
-
-	intserv = get_property(np, "ibm,ppc-interrupt-server#s", &len);
-	if (!intserv)
-		return;
-
-	nthreads = len / sizeof(u32);
-
-	lock_cpu_hotplug();
-	for (i = 0; i < nthreads; i++) {
-		for_each_present_cpu(cpu) {
-			if (get_hard_smp_processor_id(cpu) != intserv[i])
-				continue;
-			BUG_ON(cpu_online(cpu));
-			cpu_clear(cpu, cpu_present_map);
-			set_hard_smp_processor_id(cpu, -1);
-			break;
-		}
-		if (cpu == NR_CPUS)
-			printk(KERN_WARNING "Could not find cpu to remove "
-			       "with physical id 0x%x\n", intserv[i]);
-	}
-	unlock_cpu_hotplug();
-}
-
-static int pSeries_smp_notifier(struct notifier_block *nb, unsigned long action, void *node)
-{
-	int err = NOTIFY_OK;
-
-	switch (action) {
-	case PSERIES_RECONFIG_ADD:
-		if (pSeries_add_processor(node))
-			err = NOTIFY_BAD;
-		break;
-	case PSERIES_RECONFIG_REMOVE:
-		pSeries_remove_processor(node);
-		break;
-	default:
-		err = NOTIFY_DONE;
-		break;
-	}
-	return err;
-}
-
-static struct notifier_block pSeries_smp_nb = {
-	.notifier_call = pSeries_smp_notifier,
-};
-
-#endif /* CONFIG_HOTPLUG_CPU */
-
 /**
  * smp_startup_cpu() - start the given cpu
  *
@@ -422,15 +231,6 @@ static void __init smp_init_pseries(void
 
 	DBG(" -> smp_init_pSeries()\n");
 
-#ifdef CONFIG_HOTPLUG_CPU
-	smp_ops->cpu_disable = pSeries_cpu_disable;
-	smp_ops->cpu_die = pSeries_cpu_die;
-
-	/* Processors can be added/removed only on LPAR */
-	if (firmware_has_feature(FW_FEATURE_LPAR))
-		pSeries_reconfig_notifier_register(&pSeries_smp_nb);
-#endif
-
 	/* Mark threads which are still spinning in hold loops. */
 	if (cpu_has_feature(CPU_FTR_SMT)) {
 		for_each_present_cpu(i) { 

[PATCH 4/5] Only enable cpu hotplug via RTAS if the required firmware support is found

[Michael Ellerman]

To support cpu hotplug on pseries we require two RTAS tokens, the cpu
hotplug machinery should only be wired up if these tokens are found in
the device tree.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
---

 arch/powerpc/platforms/pseries/hotplug-cpu.c |   17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

Index: powerpc/arch/powerpc/platforms/pseries/hotplug-cpu.c
===================================================================
--- powerpc.orig/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ powerpc/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -64,6 +64,8 @@ static void pSeries_mach_cpu_die(void)
 	for(;;);
 }
 
+static int qcss_tok;	/* query-cpu-stopped-state token */
+
 /* Get state of physical CPU.
  * Return codes:
  *	0	- The processor is in the RTAS stopped state
@@ -74,12 +76,8 @@ static void pSeries_mach_cpu_die(void)
  */
 static int query_cpu_stopped(unsigned int pcpu)
 {
-	int cpu_status;
-	int status, qcss_tok;
+	int cpu_status, status;
 
-	qcss_tok = rtas_token("query-cpu-stopped-state");
-	if (qcss_tok == RTAS_UNKNOWN_SERVICE)
-		return -1;
 	status = rtas_call(qcss_tok, 1, 2, &cpu_status, pcpu);
 	if (status != 0) {
 		printk(KERN_ERR
@@ -254,9 +252,16 @@ static struct notifier_block pSeries_smp
 static int __init pseries_cpu_hotplug_init(void)
 {
 	rtas_stop_self_args.token = rtas_token("stop-self");
+	qcss_tok = rtas_token("query-cpu-stopped-state");
 
-	ppc_md.cpu_die = pSeries_mach_cpu_die;
+	if (rtas_stop_self_args.token == RTAS_UNKNOWN_SERVICE ||
+			qcss_tok == RTAS_UNKNOWN_SERVICE) {
+		printk(KERN_INFO "CPU Hotplug not supported by firmware "
+				"- disabling.\n");
+		return 0;
+	}
 
+	ppc_md.cpu_die = pSeries_mach_cpu_die;
 	smp_ops->cpu_disable = pSeries_cpu_disable;
 	smp_ops->cpu_die = pSeries_cpu_die;
 

[PATCH 5/5] Cleanup pass over platforms/pseries/hotplug-cpu.c

[Michael Ellerman]

Purely cosmetic. Change pSeries to pseries inline with other parts of the
kernel, and fix an overly long line.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
---

 arch/powerpc/platforms/pseries/hotplug-cpu.c |   29 +++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

Index: powerpc/arch/powerpc/platforms/pseries/hotplug-cpu.c
===================================================================
--- powerpc.orig/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ powerpc/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -53,7 +53,7 @@ static void rtas_stop_self(void)
 	panic("Alas, I survived.\n");
 }
 
-static void pSeries_mach_cpu_die(void)
+static void pseries_mach_cpu_die(void)
 {
 	local_irq_disable();
 	idle_task_exit();
@@ -88,7 +88,7 @@ static int query_cpu_stopped(unsigned in
 	return cpu_status;
 }
 
-static int pSeries_cpu_disable(void)
+static int pseries_cpu_disable(void)
 {
 	int cpu = smp_processor_id();
 
@@ -104,7 +104,7 @@ static int pSeries_cpu_disable(void)
 	return 0;
 }
 
-static void pSeries_cpu_die(unsigned int cpu)
+static void pseries_cpu_die(unsigned int cpu)
 {
 	int tries;
 	int cpu_status;
@@ -136,7 +136,7 @@ static void pSeries_cpu_die(unsigned int
  * the logical ids for sibling SMT threads x and y are adjacent, such
  * that x^1 == y and y^1 == x.
  */
-static int pSeries_add_processor(struct device_node *np)
+static int pseries_add_processor(struct device_node *np)
 {
 	unsigned int cpu;
 	cpumask_t candidate_map, tmp = CPU_MASK_NONE;
@@ -197,7 +197,7 @@ out_unlock:
  * the hard id in the paca(s) to -1 to be consistent with boot time
  * convention for non-present cpus.
  */
-static void pSeries_remove_processor(struct device_node *np)
+static void pseries_remove_processor(struct device_node *np)
 {
 	unsigned int cpu;
 	int len, nthreads, i;
@@ -226,17 +226,18 @@ static void pSeries_remove_processor(str
 	unlock_cpu_hotplug();
 }
 
-static int pSeries_smp_notifier(struct notifier_block *nb, unsigned long action, void *node)
+static int pseries_smp_notifier(struct notifier_block *nb,
+				unsigned long action, void *node)
 {
 	int err = NOTIFY_OK;
 
 	switch (action) {
 	case PSERIES_RECONFIG_ADD:
-		if (pSeries_add_processor(node))
+		if (pseries_add_processor(node))
 			err = NOTIFY_BAD;
 		break;
 	case PSERIES_RECONFIG_REMOVE:
-		pSeries_remove_processor(node);
+		pseries_remove_processor(node);
 		break;
 	default:
 		err = NOTIFY_DONE;
@@ -245,8 +246,8 @@ static int pSeries_smp_notifier(struct n
 	return err;
 }
 
-static struct notifier_block pSeries_smp_nb = {
-	.notifier_call = pSeries_smp_notifier,
+static struct notifier_block pseries_smp_nb = {
+	.notifier_call = pseries_smp_notifier,
 };
 
 static int __init pseries_cpu_hotplug_init(void)
@@ -261,13 +262,13 @@ static int __init pseries_cpu_hotplug_in
 		return 0;
 	}
 
-	ppc_md.cpu_die = pSeries_mach_cpu_die;
-	smp_ops->cpu_disable = pSeries_cpu_disable;
-	smp_ops->cpu_die = pSeries_cpu_die;
+	ppc_md.cpu_die = pseries_mach_cpu_die;
+	smp_ops->cpu_disable = pseries_cpu_disable;
+	smp_ops->cpu_die = pseries_cpu_die;
 
 	/* Processors can be added/removed only on LPAR */
 	if (firmware_has_feature(FW_FEATURE_LPAR))
-		pSeries_reconfig_notifier_register(&pSeries_smp_nb);
+		pSeries_reconfig_notifier_register(&pseries_smp_nb);
 
 	return 0;
 }

Re: [PATCH 1/5] Move rtas_stop_self() into platforms/pseries/hotplug-cpu.c

[Linas Vepstas]

On Tue, Dec 05, 2006 at 05:52:36PM +1100, Michael Ellerman wrote:
> As the first step in consolidating the pseries hotplug cpu code,
> 
> Signed-off-by: Michael Ellerman <michael@ellerman.id.au>

As per previous discussion,

Acked-by: Linas Vepstas <linas@austin.ibm.cm>

--linas