[PATCH 19/22] ARM: CPU hotplug: move cpu_killed completion to core code
Russell King - ARM Linux
linux at arm.linux.org.uk
Fri Dec 3 15:25:22 EST 2010
We always need to wait for the dying CPU to reach a safe state before
taking it down, irrespective of the requirements of the platform.
Move the completion code into the ARM SMP hotplug code rather than
having each platform re-implement this.
Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
arch/arm/kernel/smp.c | 14 +++++++++++++-
arch/arm/mach-omap2/omap-hotplug.c | 8 ++------
arch/arm/mach-realview/hotplug.c | 8 +-------
arch/arm/mach-s5pv310/hotplug.c | 8 +-------
arch/arm/mach-tegra/hotplug.c | 8 +-------
arch/arm/mach-ux500/hotplug.c | 8 +-------
6 files changed, 19 insertions(+), 35 deletions(-)
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 1f1de2b..bebe3bd 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -24,6 +24,7 @@
#include <linux/irq.h>
#include <linux/percpu.h>
#include <linux/clockchips.h>
+#include <linux/completion.h>
#include <asm/atomic.h>
#include <asm/cacheflush.h>
@@ -238,12 +239,20 @@ int __cpu_disable(void)
return 0;
}
+static DECLARE_COMPLETION(cpu_died);
+
/*
* called on the thread which is asking for a CPU to be shutdown -
* waits until shutdown has completed, or it is timed out.
*/
void __cpu_die(unsigned int cpu)
{
+ if (wait_for_completion_timeout(&cpu_died, 5000)) {
+ printk(KERN_ERR "CPU%u: cpu didn't die\n", cpu);
+ return;
+ }
+ printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
+
if (!platform_cpu_kill(cpu))
printk("CPU%u: unable to kill\n", cpu);
}
@@ -263,9 +272,12 @@ void __ref cpu_die(void)
local_irq_disable();
idle_task_exit();
+ /* Tell __cpu_die() that this CPU is now safe to dispose of */
+ complete(&cpu_died);
+
/*
* actual CPU shutdown procedure is at least platform (if not
- * CPU) specific
+ * CPU) specific.
*/
platform_cpu_die(cpu);
diff --git a/arch/arm/mach-omap2/omap-hotplug.c b/arch/arm/mach-omap2/omap-hotplug.c
index 6cee456..ace979d 100644
--- a/arch/arm/mach-omap2/omap-hotplug.c
+++ b/arch/arm/mach-omap2/omap-hotplug.c
@@ -17,16 +17,13 @@
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>
-#include <linux/completion.h>
#include <asm/cacheflush.h>
#include <mach/omap4-common.h>
-static DECLARE_COMPLETION(cpu_killed);
-
int platform_cpu_kill(unsigned int cpu)
{
- return wait_for_completion_timeout(&cpu_killed, 5000);
+ return 1;
}
/*
@@ -42,8 +39,7 @@ void platform_cpu_die(unsigned int cpu)
this_cpu, cpu);
BUG();
}
- pr_notice("CPU%u: shutdown\n", cpu);
- complete(&cpu_killed);
+
flush_cache_all();
dsb();
diff --git a/arch/arm/mach-realview/hotplug.c b/arch/arm/mach-realview/hotplug.c
index f95521a..7d58c16 100644
--- a/arch/arm/mach-realview/hotplug.c
+++ b/arch/arm/mach-realview/hotplug.c
@@ -11,14 +11,11 @@
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>
-#include <linux/completion.h>
#include <asm/cacheflush.h>
extern volatile int pen_release;
-static DECLARE_COMPLETION(cpu_killed);
-
static inline void cpu_enter_lowpower(void)
{
unsigned int v;
@@ -95,7 +92,7 @@ static inline void platform_do_lowpower(unsigned int cpu)
int platform_cpu_kill(unsigned int cpu)
{
- return wait_for_completion_timeout(&cpu_killed, 5000);
+ return 1;
}
/*
@@ -115,9 +112,6 @@ void platform_cpu_die(unsigned int cpu)
}
#endif
- printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
- complete(&cpu_killed);
-
/*
* we're ready for shutdown now, so do it
*/
diff --git a/arch/arm/mach-s5pv310/hotplug.c b/arch/arm/mach-s5pv310/hotplug.c
index 03652c3..d7be70a 100644
--- a/arch/arm/mach-s5pv310/hotplug.c
+++ b/arch/arm/mach-s5pv310/hotplug.c
@@ -13,14 +13,11 @@
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>
-#include <linux/completion.h>
#include <asm/cacheflush.h>
extern volatile int pen_release;
-static DECLARE_COMPLETION(cpu_killed);
-
static inline void cpu_enter_lowpower(void)
{
unsigned int v;
@@ -98,7 +95,7 @@ static inline void platform_do_lowpower(unsigned int cpu)
int platform_cpu_kill(unsigned int cpu)
{
- return wait_for_completion_timeout(&cpu_killed, 5000);
+ return 1;
}
/*
@@ -118,9 +115,6 @@ void platform_cpu_die(unsigned int cpu)
}
#endif
- printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
- complete(&cpu_killed);
-
/*
* we're ready for shutdown now, so do it
*/
diff --git a/arch/arm/mach-tegra/hotplug.c b/arch/arm/mach-tegra/hotplug.c
index 8e7f115..ecaa41c 100644
--- a/arch/arm/mach-tegra/hotplug.c
+++ b/arch/arm/mach-tegra/hotplug.c
@@ -11,12 +11,9 @@
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>
-#include <linux/completion.h>
#include <asm/cacheflush.h>
-static DECLARE_COMPLETION(cpu_killed);
-
static inline void cpu_enter_lowpower(void)
{
unsigned int v;
@@ -94,7 +91,7 @@ static inline void platform_do_lowpower(unsigned int cpu)
int platform_cpu_kill(unsigned int cpu)
{
- return wait_for_completion_timeout(&cpu_killed, 5000);
+ return 1;
}
/*
@@ -114,9 +111,6 @@ void platform_cpu_die(unsigned int cpu)
}
#endif
- printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
- complete(&cpu_killed);
-
/*
* we're ready for shutdown now, so do it
*/
diff --git a/arch/arm/mach-ux500/hotplug.c b/arch/arm/mach-ux500/hotplug.c
index b782a03..7a4890b 100644
--- a/arch/arm/mach-ux500/hotplug.c
+++ b/arch/arm/mach-ux500/hotplug.c
@@ -11,14 +11,11 @@
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>
-#include <linux/completion.h>
#include <asm/cacheflush.h>
extern volatile int pen_release;
-static DECLARE_COMPLETION(cpu_killed);
-
static inline void platform_do_lowpower(unsigned int cpu)
{
flush_cache_all();
@@ -38,7 +35,7 @@ static inline void platform_do_lowpower(unsigned int cpu)
int platform_cpu_kill(unsigned int cpu)
{
- return wait_for_completion_timeout(&cpu_killed, 5000);
+ return 1;
}
/*
@@ -58,9 +55,6 @@ void platform_cpu_die(unsigned int cpu)
}
#endif
- printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
- complete(&cpu_killed);
-
/* directly enter low power state, skipping secure registers */
platform_do_lowpower(cpu);
}
--
1.6.2.5
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