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authorJens Axboe <jens.axboe@oracle.com>2008-06-26 11:21:54 +0200
committerJens Axboe <jens.axboe@oracle.com>2008-06-26 11:21:54 +0200
commit3b16cf874861436725c43ba0b68bdd799297be7c (patch)
tree8e48647e3dce5dde6917f260f93c4b9f19945c55 /arch/x86/kernel/smp.c
parent3d4422332711ef48ef0f132f1fcbfcbd56c7f3d1 (diff)
x86: convert to generic helpers for IPI function calls
This converts x86, x86-64, and xen to use the new helpers for smp_call_function() and friends, and adds support for smp_call_function_single(). Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Diffstat (limited to 'arch/x86/kernel/smp.c')
-rw-r--r--arch/x86/kernel/smp.c158
1 files changed, 20 insertions, 138 deletions
diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
index 0cb7aadc87cd..575aa3d7248a 100644
--- a/arch/x86/kernel/smp.c
+++ b/arch/x86/kernel/smp.c
@@ -121,132 +121,23 @@ static void native_smp_send_reschedule(int cpu)
send_IPI_mask(cpumask_of_cpu(cpu), RESCHEDULE_VECTOR);
}
-/*
- * Structure and data for smp_call_function(). This is designed to minimise
- * static memory requirements. It also looks cleaner.
- */
-static DEFINE_SPINLOCK(call_lock);
-
-struct call_data_struct {
- void (*func) (void *info);
- void *info;
- atomic_t started;
- atomic_t finished;
- int wait;
-};
-
-void lock_ipi_call_lock(void)
+void native_send_call_func_single_ipi(int cpu)
{
- spin_lock_irq(&call_lock);
-}
-
-void unlock_ipi_call_lock(void)
-{
- spin_unlock_irq(&call_lock);
-}
-
-static struct call_data_struct *call_data;
-
-static void __smp_call_function(void (*func) (void *info), void *info,
- int nonatomic, int wait)
-{
- struct call_data_struct data;
- int cpus = num_online_cpus() - 1;
-
- if (!cpus)
- return;
-
- data.func = func;
- data.info = info;
- atomic_set(&data.started, 0);
- data.wait = wait;
- if (wait)
- atomic_set(&data.finished, 0);
-
- call_data = &data;
- mb();
-
- /* Send a message to all other CPUs and wait for them to respond */
- send_IPI_allbutself(CALL_FUNCTION_VECTOR);
-
- /* Wait for response */
- while (atomic_read(&data.started) != cpus)
- cpu_relax();
-
- if (wait)
- while (atomic_read(&data.finished) != cpus)
- cpu_relax();
+ send_IPI_mask(cpumask_of_cpu(cpu), CALL_FUNCTION_SINGLE_VECTOR);
}
-
-/**
- * smp_call_function_mask(): Run a function on a set of other CPUs.
- * @mask: The set of cpus to run on. Must not include the current cpu.
- * @func: The function to run. This must be fast and non-blocking.
- * @info: An arbitrary pointer to pass to the function.
- * @wait: If true, wait (atomically) until function has completed on other CPUs.
- *
- * Returns 0 on success, else a negative status code.
- *
- * If @wait is true, then returns once @func has returned; otherwise
- * it returns just before the target cpu calls @func.
- *
- * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler or from a bottom half handler.
- */
-static int
-native_smp_call_function_mask(cpumask_t mask,
- void (*func)(void *), void *info,
- int wait)
+void native_send_call_func_ipi(cpumask_t mask)
{
- struct call_data_struct data;
cpumask_t allbutself;
- int cpus;
-
- /* Can deadlock when called with interrupts disabled */
- WARN_ON(irqs_disabled());
-
- /* Holding any lock stops cpus from going down. */
- spin_lock(&call_lock);
allbutself = cpu_online_map;
cpu_clear(smp_processor_id(), allbutself);
- cpus_and(mask, mask, allbutself);
- cpus = cpus_weight(mask);
-
- if (!cpus) {
- spin_unlock(&call_lock);
- return 0;
- }
-
- data.func = func;
- data.info = info;
- atomic_set(&data.started, 0);
- data.wait = wait;
- if (wait)
- atomic_set(&data.finished, 0);
-
- call_data = &data;
- wmb();
-
- /* Send a message to other CPUs */
if (cpus_equal(mask, allbutself) &&
cpus_equal(cpu_online_map, cpu_callout_map))
send_IPI_allbutself(CALL_FUNCTION_VECTOR);
else
send_IPI_mask(mask, CALL_FUNCTION_VECTOR);
-
- /* Wait for response */
- while (atomic_read(&data.started) != cpus)
- cpu_relax();
-
- if (wait)
- while (atomic_read(&data.finished) != cpus)
- cpu_relax();
- spin_unlock(&call_lock);
-
- return 0;
}
static void stop_this_cpu(void *dummy)
@@ -268,18 +159,13 @@ static void stop_this_cpu(void *dummy)
static void native_smp_send_stop(void)
{
- int nolock;
unsigned long flags;
if (reboot_force)
return;
- /* Don't deadlock on the call lock in panic */
- nolock = !spin_trylock(&call_lock);
+ smp_call_function(stop_this_cpu, NULL, 0, 0);
local_irq_save(flags);
- __smp_call_function(stop_this_cpu, NULL, 0, 0);
- if (!nolock)
- spin_unlock(&call_lock);
disable_local_APIC();
local_irq_restore(flags);
}
@@ -301,33 +187,28 @@ void smp_reschedule_interrupt(struct pt_regs *regs)
void smp_call_function_interrupt(struct pt_regs *regs)
{
- void (*func) (void *info) = call_data->func;
- void *info = call_data->info;
- int wait = call_data->wait;
-
ack_APIC_irq();
- /*
- * Notify initiating CPU that I've grabbed the data and am
- * about to execute the function
- */
- mb();
- atomic_inc(&call_data->started);
- /*
- * At this point the info structure may be out of scope unless wait==1
- */
irq_enter();
- (*func)(info);
+ generic_smp_call_function_interrupt();
#ifdef CONFIG_X86_32
__get_cpu_var(irq_stat).irq_call_count++;
#else
add_pda(irq_call_count, 1);
#endif
irq_exit();
+}
- if (wait) {
- mb();
- atomic_inc(&call_data->finished);
- }
+void smp_call_function_single_interrupt(void)
+{
+ ack_APIC_irq();
+ irq_enter();
+ generic_smp_call_function_single_interrupt();
+#ifdef CONFIG_X86_32
+ __get_cpu_var(irq_stat).irq_call_count++;
+#else
+ add_pda(irq_call_count, 1);
+#endif
+ irq_exit();
}
struct smp_ops smp_ops = {
@@ -338,7 +219,8 @@ struct smp_ops smp_ops = {
.smp_send_stop = native_smp_send_stop,
.smp_send_reschedule = native_smp_send_reschedule,
- .smp_call_function_mask = native_smp_call_function_mask,
+
+ .send_call_func_ipi = native_send_call_func_ipi,
+ .send_call_func_single_ipi = native_send_call_func_single_ipi,
};
EXPORT_SYMBOL_GPL(smp_ops);
-