[PATCH] MIPS: add smp_call_function_single()

Stephane Eranian
2007-07-27T12:46:38Z

[MIPS] add smp_call_function_single()

signed-off-by: Stephane Eranian <eranian@hpl.hp.com>
signed-off-by: Phil Mucci <mucci@cs.utk.edu>

diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c
index be7362b..9e376e2 100644
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -193,6 +193,53 @@ void smp_call_function_interrupt(void)
}
}

+int smp_call_function_single(int cpu, void (*func) (void *info), void *info, int retry,
+ int wait)
+{
+ struct call_data_struct data;
+ int me = smp_processor_id();
+
+ /*
+ * Can die spectacularly if this CPU isn't yet marked online
+ */
+ BUG_ON(!cpu_online(me));
+ if (cpu == me) {
+ WARN_ON(1);
+ return -EBUSY;
+ }
+
+ /* 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);
+
+ spin_lock(&smp_call_lock);
+ call_data = &data;
+ mb();
+
+ /* Send a message to the other CPU */
+ core_send_ipi(cpu, SMP_CALL_FUNCTION);
+
+ /* Wait for response */
+ /* FIXME: lock-up detection, backtrace on lock-up */
+ while (atomic_read(&data.started) != 1)
+ barrier();
+
+ if (wait)
+ while (atomic_read(&data.finished) != 1)
+ barrier();
+ call_data = NULL;
+ spin_unlock(&smp_call_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL(smp_call_function_single);
+
static void stop_this_cpu(void *dummy)
{
/*
diff --git a/include/asm-mips/smp.h b/include/asm-mips/smp.h
index 13aef6a..5acbf38 100644
--- a/include/asm-mips/smp.h
+++ b/include/asm-mips/smp.h
@@ -102,6 +102,8 @@ static inline void smp_send_reschedule(int cpu)
core_send_ipi(cpu, SMP_RESCHEDULE_YOURSELF);
}

+extern int smp_call_function_single(int cpuid, void (*func) (void *info),
+ void *info, int retry, int wait);
extern asmlinkage void smp_call_function_interrupt(void);

#endif /* CONFIG_SMP */