[IA64] Implement smp_call_function_mask for ia64
This interface provides more flexible functionality for smp
infrastructure ... e.g. KVM frequently needs to operate on
a subset of cpus.
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/arch/ia64/kernel/smp.c b/arch/ia64/kernel/smp.c
index 4e446aa..9a9d4c4 100644
--- a/arch/ia64/kernel/smp.c
+++ b/arch/ia64/kernel/smp.c
@@ -213,6 +213,19 @@
* Called with preemption disabled.
*/
static inline void
+send_IPI_mask(cpumask_t mask, int op)
+{
+ unsigned int cpu;
+
+ for_each_cpu_mask(cpu, mask) {
+ send_IPI_single(cpu, op);
+ }
+}
+
+/*
+ * Called with preemption disabled.
+ */
+static inline void
send_IPI_all (int op)
{
int i;
@@ -401,6 +414,75 @@
}
EXPORT_SYMBOL(smp_call_function_single);
+/**
+ * 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.
+ */
+int smp_call_function_mask(cpumask_t mask,
+ void (*func)(void *), void *info,
+ int wait)
+{
+ struct call_data_struct data;
+ cpumask_t allbutself;
+ int cpus;
+
+ 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;
+ }
+
+ /* Can deadlock when called with interrupts disabled */
+ WARN_ON(irqs_disabled());
+
+ 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(); /* ensure store to call_data precedes setting of IPI_CALL_FUNC*/
+
+ /* Send a message to other CPUs */
+ if (cpus_equal(mask, allbutself))
+ send_IPI_allbutself(IPI_CALL_FUNC);
+ else
+ send_IPI_mask(mask, IPI_CALL_FUNC);
+
+ /* Wait for response */
+ while (atomic_read(&data.started) != cpus)
+ cpu_relax();
+
+ if (wait)
+ while (atomic_read(&data.finished) != cpus)
+ cpu_relax();
+ call_data = NULL;
+
+ spin_unlock(&call_lock);
+ return 0;
+
+}
+EXPORT_SYMBOL(smp_call_function_mask);
+
/*
* this function sends a 'generic call function' IPI to all other CPUs
* in the system.
diff --git a/include/asm-ia64/smp.h b/include/asm-ia64/smp.h
index 4fa733d..ec5f355 100644
--- a/include/asm-ia64/smp.h
+++ b/include/asm-ia64/smp.h
@@ -38,6 +38,9 @@
return lid.f.id << 8 | lid.f.eid;
}
+extern int smp_call_function_mask(cpumask_t mask, void (*func)(void *),
+ void *info, int wait);
+
#define hard_smp_processor_id() ia64_get_lid()
#ifdef CONFIG_SMP