Re: [PATCH] x86: call machine_shutdown and stop all CPUs in native_machine_halt

From: Ivan Vecera
Date: Tue Oct 21 2008 - 08:37:17 EST


Ingo Molnar wrote:
> the code in arch/x86/kernel/smp.c::stop_this_cpu() is very similar to
> this and could be shared. You could move the stop_this_cpu() function to
> arch/x86/kernel/process.c (out of smp.c), so that it can be used by
> reboot.c.
>
Yes, this make sense. Here is the patch.

Ivan

---
arch/x86/kernel/process.c | 16 ++++++++++++++++
arch/x86/kernel/reboot.c | 5 +++++
arch/x86/kernel/smp.c | 13 -------------
include/asm-x86/system.h | 2 ++
4 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index c622772..af6904e 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -8,6 +8,7 @@
#include <linux/pm.h>
#include <linux/clockchips.h>
#include <asm/system.h>
+#include <asm/apic.h>

unsigned long idle_halt;
EXPORT_SYMBOL(idle_halt);
@@ -122,6 +123,21 @@ void default_idle(void)
EXPORT_SYMBOL(default_idle);
#endif

+void stop_this_cpu(void *dummy)
+{
+ local_irq_disable();
+ /*
+ * Remove this CPU:
+ */
+ cpu_clear(smp_processor_id(), cpu_online_map);
+#ifdef CONFIG_X86_LOCAL_APIC
+ disable_local_APIC();
+#endif
+ if (hlt_works(smp_processor_id()))
+ for (;;) halt();
+ for (;;);
+}
+
static void do_nothing(void *unused)
{
}
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index f4c93f1..3113d9e 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -465,6 +465,11 @@ static void native_machine_restart(char *__unused)

static void native_machine_halt(void)
{
+ /* stop other cpus and apics */
+ machine_shutdown();
+
+ /* stop this cpu */
+ stop_this_cpu(NULL);
}

static void native_machine_power_off(void)
diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
index 18f9b19..3f92b13 100644
--- a/arch/x86/kernel/smp.c
+++ b/arch/x86/kernel/smp.c
@@ -140,19 +140,6 @@ void native_send_call_func_ipi(cpumask_t mask)
send_IPI_mask(mask, CALL_FUNCTION_VECTOR);
}

-static void stop_this_cpu(void *dummy)
-{
- local_irq_disable();
- /*
- * Remove this CPU:
- */
- cpu_clear(smp_processor_id(), cpu_online_map);
- disable_local_APIC();
- if (hlt_works(smp_processor_id()))
- for (;;) halt();
- for (;;);
-}
-
/*
* this function calls the 'stop' function on all other CPUs in the system.
*/
diff --git a/include/asm-x86/system.h b/include/asm-x86/system.h
index b20c894..17ac753 100644
--- a/include/asm-x86/system.h
+++ b/include/asm-x86/system.h
@@ -314,6 +314,8 @@ extern void free_init_pages(char *what, unsigned long begin, unsigned long end);

void default_idle(void);

+void stop_this_cpu(void *dummy);
+
/*
* Force strict CPU ordering.
* And yes, this is required on UP too when we're talking
--
1.5.6.3
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