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yaml
---
r: 53733
b: refs/heads/master
c: 9964cf7
h: refs/heads/master
i:
  53731: 86361ac
v: v3
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Jan Beulich authored and Andi Kleen committed May 2, 2007
1 parent b4eb571 commit a55aafb
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Showing 4 changed files with 49 additions and 50 deletions.
2 changes: 1 addition & 1 deletion [refs]
Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: b0354795c9c8fef2fadf8f867586c78efd9a1dc9
refs/heads/master: 9964cf7d776600724ef5f1b33303ceadc588b8ba
68 changes: 38 additions & 30 deletions trunk/arch/i386/kernel/smp.c
Original file line number Diff line number Diff line change
Expand Up @@ -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;
Expand All @@ -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;
Expand All @@ -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();
Expand All @@ -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);
}

/*
Expand Down
28 changes: 10 additions & 18 deletions trunk/arch/x86_64/kernel/smp.c
Original file line number Diff line number Diff line change
Expand Up @@ -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);
}

/*
Expand Down
1 change: 0 additions & 1 deletion trunk/include/asm-x86_64/smp.h
Original file line number Diff line number Diff line change
Expand Up @@ -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];
Expand Down

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