Re: [PATCH] irq_work: unhide irq_work_queue_on declaration on non-SMP

The cpufreq code uses 'if (IS_ENABLED(CONFIG_SMP))' to check
whether it should queue a task on the local CPU or a remote
one, however the irq_work_queue_on() function is not declared
when CONFIG_SMP is not set:

drivers/cpufreq/cpufreq_governor.c: In function 'gov_queue_irq_work':
drivers/cpufreq/cpufreq_governor.c:251:3: error: implicit declaration of function 'irq_work_queue_on' [-Werror=implicit-function-declaration]
   irq_work_queue_on(&policy_dbs->irq_work, smp_processor_id());

This changes the conditional declaration so that irq_work_queue_on
just queues the irq work on the only available CPU when CONFIG_SMP
is not set, which is presumably what most people need anyway.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 0144fa03ef46 ("cpufreq: governor: Replace timers with utilization update callbacks")

diff --git a/include/linux/irq_work.h b/include/linux/irq_work.h
index 47b9ebd4a74f..c9bde50ef317 100644
--- a/include/linux/irq_work.h
+++ b/include/linux/irq_work.h

@@ -33,9 +33,13 @@ void init_irq_work(struct irq_work *work, void (*func)(struct irq_work *))
 #define DEFINE_IRQ_WORK(name, _f) struct irq_work name = { .func = (_f), }

 bool irq_work_queue(struct irq_work *work);
-
 #ifdef CONFIG_SMP
 bool irq_work_queue_on(struct irq_work *work, int cpu);
+#else
+static inline bool irq_work_queue_on(struct irq_work *work, int cpu)
+{
+       return irq_work_queue(work);
+}
 #endif

 void irq_work_tick(void);