From: Peter Watkins <pwatkins@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Peter Watkins <pwatkins@xxxxxxxxxxxxxxxxxxxx>
---
arch/mips/kernel/smp.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++
include/asm-mips/smp.h | 2 ++
2 files changed, 52 insertions(+), 0 deletions(-)
diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c
index 67edfa7..26f0f55 100644
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -203,6 +203,56 @@ 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;
+ }
+
+ if (!cpu_online(cpu))
+ 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);
+
+ spin_lock(&smp_call_lock);
+ call_data = &data;
+ smp_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;
+}
+
static void stop_this_cpu(void *dummy)
{
/*
diff --git a/include/asm-mips/smp.h b/include/asm-mips/smp.h
index 1608fd7..1aa6bb4 100644
--- a/include/asm-mips/smp.h
+++ b/include/asm-mips/smp.h
@@ -109,6 +109,8 @@ static inline void smp_send_reschedule(i
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 */
--
1.4.2.4
