csd->flags &= ~CSD_FLAG_LOCK;
}
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_data, csd_data);
+
/*
* Insert a previously allocated call_single_data element
* for execution on the given CPU. data must already have
* ->func, ->info, and ->flags set.
*/
-static void generic_exec_single(int cpu, struct call_single_data *csd, int wait)
+static int generic_exec_single(int cpu, struct call_single_data *csd,
+ smp_call_func_t func, void *info, int wait)
{
+ struct call_single_data csd_stack = { .flags = 0 };
+ unsigned long flags;
+
+
+ if (cpu == smp_processor_id()) {
+ local_irq_save(flags);
+ func(info);
+ local_irq_restore(flags);
+ return 0;
+ }
+
+
+ if ((unsigned)cpu >= nr_cpu_ids || !cpu_online(cpu))
+ return -ENXIO;
+
+
+ if (!csd) {
+ csd = &csd_stack;
+ if (!wait)
+ csd = &__get_cpu_var(csd_data);
+ }
+
+ csd_lock(csd);
+
+ csd->func = func;
+ csd->info = info;
+
if (wait)
csd->flags |= CSD_FLAG_WAIT;
if (wait)
csd_lock_wait(csd);
+
+ return 0;
}
/*
*/
void generic_smp_call_function_single_interrupt(void)
{
- struct llist_node *entry, *next;
+ struct llist_node *entry;
+ struct call_single_data *csd, *csd_next;
/*
* Shouldn't receive this interrupt on a cpu that is not yet online.
entry = llist_del_all(&__get_cpu_var(call_single_queue));
entry = llist_reverse_order(entry);
- while (entry) {
- struct call_single_data *csd;
-
- next = entry->next;
-
- csd = llist_entry(entry, struct call_single_data, llist);
+ llist_for_each_entry_safe(csd, csd_next, entry, llist) {
csd->func(csd->info);
csd_unlock(csd);
-
- entry = next;
}
}
-static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_data, csd_data);
-
/*
* smp_call_function_single - Run a function on a specific CPU
* @func: The function to run. This must be fast and non-blocking.
int smp_call_function_single(int cpu, smp_call_func_t func, void *info,
int wait)
{
- struct call_single_data d = {
- .flags = 0,
- };
- unsigned long flags;
int this_cpu;
- int err = 0;
+ int err;
/*
* prevent preemption and reschedule on another processor,
WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled()
&& !oops_in_progress);
- if (cpu == this_cpu) {
- local_irq_save(flags);
- func(info);
- local_irq_restore(flags);
- } else {
- if ((unsigned)cpu < nr_cpu_ids && cpu_online(cpu)) {
- struct call_single_data *csd = &d;
+ err = generic_exec_single(cpu, NULL, func, info, wait);
- if (!wait)
- csd = &__get_cpu_var(csd_data);
+ put_cpu();
- csd_lock(csd);
+ return err;
+}
+EXPORT_SYMBOL(smp_call_function_single);
- csd->func = func;
- csd->info = info;
- generic_exec_single(cpu, csd, wait);
- } else {
- err = -ENXIO; /* CPU not online */
- }
- }
+/**
+ * __smp_call_function_single(): Run a function on a specific CPU
+ * @cpu: The CPU to run on.
+ * @csd: Pre-allocated and setup data structure
+ * @wait: If true, wait until function has completed on specified CPU.
+ *
+ * Like smp_call_function_single(), but allow caller to pass in a
+ * pre-allocated data structure. Useful for embedding @data inside
+ * other structures, for instance.
+ */
+int __smp_call_function_single(int cpu, struct call_single_data *csd, int wait)
+{
+ int err = 0;
+ int this_cpu;
+
+ this_cpu = get_cpu();
+ /*
+ * Can deadlock when called with interrupts disabled.
+ * We allow cpu's that are not yet online though, as no one else can
+ * send smp call function interrupt to this cpu and as such deadlocks
+ * can't happen.
+ */
+ WARN_ON_ONCE(cpu_online(this_cpu) && wait && irqs_disabled()
+ && !oops_in_progress);
+ err = generic_exec_single(cpu, csd, csd->func, csd->info, wait);
put_cpu();
return err;
}
-EXPORT_SYMBOL(smp_call_function_single);
+EXPORT_SYMBOL_GPL(__smp_call_function_single);
/*
* smp_call_function_any - Run a function on any of the given cpus
}
EXPORT_SYMBOL_GPL(smp_call_function_any);
-/**
- * __smp_call_function_single(): Run a function on a specific CPU
- * @cpu: The CPU to run on.
- * @data: Pre-allocated and setup data structure
- * @wait: If true, wait until function has completed on specified CPU.
- *
- * Like smp_call_function_single(), but allow caller to pass in a
- * pre-allocated data structure. Useful for embedding @data inside
- * other structures, for instance.
- */
-void __smp_call_function_single(int cpu, struct call_single_data *csd,
- int wait)
-{
- unsigned int this_cpu;
- unsigned long flags;
-
- this_cpu = get_cpu();
- /*
- * Can deadlock when called with interrupts disabled.
- * We allow cpu's that are not yet online though, as no one else can
- * send smp call function interrupt to this cpu and as such deadlocks
- * can't happen.
- */
- WARN_ON_ONCE(cpu_online(smp_processor_id()) && wait && irqs_disabled()
- && !oops_in_progress);
-
- if (cpu == this_cpu) {
- local_irq_save(flags);
- csd->func(csd->info);
- local_irq_restore(flags);
- } else {
- csd_lock(csd);
- generic_exec_single(cpu, csd, wait);
- }
- put_cpu();
-}
-EXPORT_SYMBOL_GPL(__smp_call_function_single);
-
/**
* smp_call_function_many(): Run a function on a set of other CPUs.
* @mask: The set of cpus to run on (only runs on online subset).
projects / linux-block.git / blobdiff