[PATCH] PPC64: Generic hotplug cpu support
From: Zwane Mwaikambo
Date: Tue Feb 01 2005 - 13:27:28 EST
Patch provides a generic hotplug cpu implementation, with the only current
user being pmac. This doesn't replace real hotplug code as is currently
used by LPAR systems. Ben i can add the additional pmac specific code to
put the processor into a sleeping state seperately. Thanks to Nathan for
testing.
arch/ppc64/Kconfig | 2
arch/ppc64/kernel/idle.c | 4 +
arch/ppc64/kernel/irq.c | 29 +++++++++++++
arch/ppc64/kernel/pSeries_setup.c | 5 +-
arch/ppc64/kernel/pmac_setup.c | 3 +
arch/ppc64/kernel/pmac_smp.c | 5 ++
arch/ppc64/kernel/setup.c | 3 -
arch/ppc64/kernel/smp.c | 80 ++++++++++++++++++++++++++++++++++++++
arch/ppc64/kernel/sysfs.c | 6 --
include/asm-ppc64/machdep.h | 1
include/asm-ppc64/smp.h | 9 +++-
11 files changed, 136 insertions(+), 11 deletions(-)
Signed-off-by: Zwane Mwaikambo <zwane@xxxxxxxxxxxxxxxx>
Index: linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/Kconfig
===================================================================
RCS file: /home/cvsroot/linux-2.6.11-rc2-mm2/arch/ppc64/Kconfig,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 Kconfig
--- linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/Kconfig 29 Jan 2005 21:29:21 -0000 1.1.1.1
+++ linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/Kconfig 1 Feb 2005 05:01:10 -0000
@@ -313,7 +313,7 @@ source "drivers/pci/Kconfig"
config HOTPLUG_CPU
bool "Support for hot-pluggable CPUs"
- depends on SMP && EXPERIMENTAL && PPC_PSERIES
+ depends on SMP && EXPERIMENTAL && (PPC_PSERIES || PPC_PMAC)
select HOTPLUG
---help---
Say Y here to be able to turn CPUs off and on.
Index: linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/idle.c
===================================================================
RCS file: /home/cvsroot/linux-2.6.11-rc2-mm2/arch/ppc64/kernel/idle.c,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 idle.c
--- linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/idle.c 29 Jan 2005 21:29:21 -0000 1.1.1.1
+++ linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/idle.c 1 Feb 2005 06:32:09 -0000
@@ -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;
}
Index: linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/irq.c
===================================================================
RCS file: /home/cvsroot/linux-2.6.11-rc2-mm2/arch/ppc64/kernel/irq.c,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 irq.c
--- linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/irq.c 29 Jan 2005 21:29:21 -0000 1.1.1.1
+++ linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/irq.c 1 Feb 2005 05:18:21 -0000
@@ -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;
/*
Index: linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/pSeries_setup.c
===================================================================
RCS file: /home/cvsroot/linux-2.6.11-rc2-mm2/arch/ppc64/kernel/pSeries_setup.c,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 pSeries_setup.c
--- linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/pSeries_setup.c 29 Jan 2005 21:29:21 -0000 1.1.1.1
+++ linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/pSeries_setup.c 1 Feb 2005 05:01:10 -0000
@@ -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,
Index: linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/pmac_setup.c
===================================================================
RCS file: /home/cvsroot/linux-2.6.11-rc2-mm2/arch/ppc64/kernel/pmac_setup.c,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 pmac_setup.c
--- linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/pmac_setup.c 29 Jan 2005 21:29:21 -0000 1.1.1.1
+++ linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/pmac_setup.c 1 Feb 2005 06:49:25 -0000
@@ -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,
Index: linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/pmac_smp.c
===================================================================
RCS file: /home/cvsroot/linux-2.6.11-rc2-mm2/arch/ppc64/kernel/pmac_smp.c,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 pmac_smp.c
--- linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/pmac_smp.c 29 Jan 2005 21:29:21 -0000 1.1.1.1
+++ linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/pmac_smp.c 1 Feb 2005 06:50:02 -0000
@@ -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
}
Index: linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/setup.c
===================================================================
RCS file: /home/cvsroot/linux-2.6.11-rc2-mm2/arch/ppc64/kernel/setup.c,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 setup.c
--- linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/setup.c 29 Jan 2005 21:29:21 -0000 1.1.1.1
+++ linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/setup.c 1 Feb 2005 06:25:29 -0000
@@ -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 (;;);
}
Index: linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/smp.c
===================================================================
RCS file: /home/cvsroot/linux-2.6.11-rc2-mm2/arch/ppc64/kernel/smp.c,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 smp.c
--- linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/smp.c 29 Jan 2005 21:29:21 -0000 1.1.1.1
+++ linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/smp.c 1 Feb 2005 06:36:42 -0000
@@ -30,6 +30,7 @@
#include <linux/err.h>
#include <linux/sysdev.h>
#include <linux/cpu.h>
+#include <linux/notifier.h>
#include <asm/ptrace.h>
#include <asm/atomic.h>
@@ -406,10 +407,89 @@ void __devinit smp_prepare_boot_cpu(void
current_set[boot_cpuid] = current->thread_info;
}
+#ifdef CONFIG_HOTPLUG_CPU
+/* State of each CPU during hotplug phases */
+DEFINE_PER_CPU(int, cpu_state) = { 0 };
+
+int generic_cpu_disable(void)
+{
+ unsigned int cpu = smp_processor_id();
+
+ if (cpu == boot_cpuid)
+ return -EBUSY;
+
+ systemcfg->processorCount--;
+ cpu_clear(cpu, cpu_online_map);
+ fixup_irqs(cpu_online_map);
+ return 0;
+}
+
+int generic_cpu_enable(unsigned int cpu)
+{
+ /* Do the normal bootup if we haven't
+ * already bootstrapped. */
+ if (system_state != SYSTEM_RUNNING)
+ return -ENOSYS;
+
+ /* get the target out of it's holding state */
+ per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
+ wmb();
+
+ while (!cpu_online(cpu))
+ cpu_relax();
+
+ fixup_irqs(cpu_online_map);
+ /* counter the irq disable in fixup_irqs */
+ local_irq_enable();
+ return 0;
+}
+
+void generic_cpu_die(unsigned int cpu)
+{
+ int i;
+
+ for (i = 0; i < 100; i++) {
+ rmb();
+ if (per_cpu(cpu_state, cpu) == CPU_DEAD)
+ return;
+ msleep(100);
+ }
+ printk(KERN_ERR "CPU%d didn't die...\n", cpu);
+}
+
+void generic_mach_cpu_die(void)
+{
+ unsigned int cpu;
+
+ local_irq_disable();
+ cpu = smp_processor_id();
+ printk(KERN_DEBUG "CPU%d offline\n", cpu);
+ __get_cpu_var(cpu_state) = CPU_DEAD;
+ wmb();
+ while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
+ cpu_relax();
+
+ flush_tlb_pending();
+ cpu_set(cpu, cpu_online_map);
+ local_irq_enable();
+}
+#endif
+
+static int __devinit cpu_enable(unsigned int cpu)
+{
+ if (smp_ops->cpu_enable)
+ return smp_ops->cpu_enable(cpu);
+
+ return -ENOSYS;
+}
+
int __devinit __cpu_up(unsigned int cpu)
{
int c;
+ if (!cpu_enable(cpu))
+ return 0;
+
/* At boot, don't bother with non-present cpus -JSCHOPP */
if (system_state < SYSTEM_RUNNING && !cpu_present(cpu))
return -ENOENT;
Index: linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/sysfs.c
===================================================================
RCS file: /home/cvsroot/linux-2.6.11-rc2-mm2/arch/ppc64/kernel/sysfs.c,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 sysfs.c
--- linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/sysfs.c 29 Jan 2005 21:29:21 -0000 1.1.1.1
+++ linux-2.6.11-rc2-mm2-ppc64/arch/ppc64/kernel/sysfs.c 1 Feb 2005 05:01:10 -0000
@@ -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)) {
Index: linux-2.6.11-rc2-mm2-ppc64/include/asm-ppc64/machdep.h
===================================================================
RCS file: /home/cvsroot/linux-2.6.11-rc2-mm2/include/asm-ppc64/machdep.h,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 machdep.h
--- linux-2.6.11-rc2-mm2-ppc64/include/asm-ppc64/machdep.h 29 Jan 2005 21:29:28 -0000 1.1.1.1
+++ linux-2.6.11-rc2-mm2-ppc64/include/asm-ppc64/machdep.h 1 Feb 2005 05:56:24 -0000
@@ -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);
};
Index: linux-2.6.11-rc2-mm2-ppc64/include/asm-ppc64/smp.h
===================================================================
RCS file: /home/cvsroot/linux-2.6.11-rc2-mm2/include/asm-ppc64/smp.h,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 smp.h
--- linux-2.6.11-rc2-mm2-ppc64/include/asm-ppc64/smp.h 29 Jan 2005 21:29:28 -0000 1.1.1.1
+++ linux-2.6.11-rc2-mm2-ppc64/include/asm-ppc64/smp.h 1 Feb 2005 06:25:08 -0000
@@ -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)
-
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