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-rw-r--r--arch/i386/kernel/smp.c68
-rw-r--r--arch/x86_64/kernel/smp.c28
-rw-r--r--include/asm-x86_64/smp.h1
3 files changed, 48 insertions, 49 deletions
diff --git a/arch/i386/kernel/smp.c b/arch/i386/kernel/smp.c
index 0e8977871b1f..0cd459baad68 100644
--- a/arch/i386/kernel/smp.c
+++ b/arch/i386/kernel/smp.c
@@ -515,35 +515,14 @@ void unlock_ipi_call_lock(void)
static struct call_data_struct *call_data;
-/**
- * smp_call_function(): Run a function on all other CPUs.
- * @func: The function to run. This must be fast and non-blocking.
- * @info: An arbitrary pointer to pass to the function.
- * @nonatomic: currently unused.
- * @wait: If true, wait (atomically) until function has completed on other CPUs.
- *
- * Returns 0 on success, else a negative status code. Does not return until
- * remote CPUs are nearly ready to execute <<func>> or are or have executed.
- *
- * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler or from a bottom half handler.
- */
-int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
- int wait)
+static void __smp_call_function(void (*func) (void *info), void *info,
+ int nonatomic, int wait)
{
struct call_data_struct data;
- int cpus;
-
- /* Holding any lock stops cpus from going down. */
- spin_lock(&call_lock);
- cpus = num_online_cpus() - 1;
- if (!cpus) {
- spin_unlock(&call_lock);
- return 0;
- }
+ int cpus = num_online_cpus() - 1;
- /* Can deadlock when called with interrupts disabled */
- WARN_ON(irqs_disabled());
+ if (!cpus)
+ return;
data.func = func;
data.info = info;
@@ -565,6 +544,30 @@ int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
if (wait)
while (atomic_read(&data.finished) != cpus)
cpu_relax();
+}
+
+/**
+ * smp_call_function(): Run a function on all other CPUs.
+ * @func: The function to run. This must be fast and non-blocking.
+ * @info: An arbitrary pointer to pass to the function.
+ * @nonatomic: currently unused.
+ * @wait: If true, wait (atomically) until function has completed on other CPUs.
+ *
+ * Returns 0 on success, else a negative status code. Does not return until
+ * remote CPUs are nearly ready to execute <<func>> or are or have executed.
+ *
+ * You must not call this function with disabled interrupts or from a
+ * hardware interrupt handler or from a bottom half handler.
+ */
+int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
+ int wait)
+{
+ /* Can deadlock when called with interrupts disabled */
+ WARN_ON(irqs_disabled());
+
+ /* Holding any lock stops cpus from going down. */
+ spin_lock(&call_lock);
+ __smp_call_function(func, info, nonatomic, wait);
spin_unlock(&call_lock);
return 0;
@@ -573,11 +576,11 @@ EXPORT_SYMBOL(smp_call_function);
static void stop_this_cpu (void * dummy)
{
+ local_irq_disable();
/*
* Remove this CPU:
*/
cpu_clear(smp_processor_id(), cpu_online_map);
- local_irq_disable();
disable_local_APIC();
if (cpu_data[smp_processor_id()].hlt_works_ok)
for(;;) halt();
@@ -590,11 +593,16 @@ static void stop_this_cpu (void * dummy)
void smp_send_stop(void)
{
- smp_call_function(stop_this_cpu, NULL, 1, 0);
+ /* Don't deadlock on the call lock in panic */
+ int nolock = !spin_trylock(&call_lock);
+ unsigned long flags;
- local_irq_disable();
+ local_irq_save(flags);
+ __smp_call_function(stop_this_cpu, NULL, 0, 0);
+ if (!nolock)
+ spin_unlock(&call_lock);
disable_local_APIC();
- local_irq_enable();
+ local_irq_restore(flags);
}
/*
diff --git a/arch/x86_64/kernel/smp.c b/arch/x86_64/kernel/smp.c
index af1ec4d23cf8..bd1d123947ce 100644
--- a/arch/x86_64/kernel/smp.c
+++ b/arch/x86_64/kernel/smp.c
@@ -452,42 +452,34 @@ int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
}
EXPORT_SYMBOL(smp_call_function);
-void smp_stop_cpu(void)
+static void stop_this_cpu(void *dummy)
{
- unsigned long flags;
+ local_irq_disable();
/*
* Remove this CPU:
*/
cpu_clear(smp_processor_id(), cpu_online_map);
- local_irq_save(flags);
disable_local_APIC();
- local_irq_restore(flags);
-}
-
-static void smp_really_stop_cpu(void *dummy)
-{
- smp_stop_cpu();
for (;;)
halt();
}
void smp_send_stop(void)
{
- int nolock = 0;
+ int nolock;
+ unsigned long flags;
+
if (reboot_force)
return;
+
/* Don't deadlock on the call lock in panic */
- if (!spin_trylock(&call_lock)) {
- /* ignore locking because we have panicked anyways */
- nolock = 1;
- }
- __smp_call_function(smp_really_stop_cpu, NULL, 0, 0);
+ nolock = !spin_trylock(&call_lock);
+ local_irq_save(flags);
+ __smp_call_function(stop_this_cpu, NULL, 0, 0);
if (!nolock)
spin_unlock(&call_lock);
-
- local_irq_disable();
disable_local_APIC();
- local_irq_enable();
+ local_irq_restore(flags);
}
/*
diff --git a/include/asm-x86_64/smp.h b/include/asm-x86_64/smp.h
index f4236d7789aa..d5704421456b 100644
--- a/include/asm-x86_64/smp.h
+++ b/include/asm-x86_64/smp.h
@@ -37,7 +37,6 @@ extern void lock_ipi_call_lock(void);
extern void unlock_ipi_call_lock(void);
extern int smp_num_siblings;
extern void smp_send_reschedule(int cpu);
-void smp_stop_cpu(void);
extern cpumask_t cpu_sibling_map[NR_CPUS];
extern cpumask_t cpu_core_map[NR_CPUS];