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-rw-r--r--include/linux/hardirq.h1
-rw-r--r--kernel/irq/manage.c70
2 files changed, 51 insertions, 20 deletions
diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
index 12d5f972f23f..cba442ec3c66 100644
--- a/include/linux/hardirq.h
+++ b/include/linux/hardirq.h
@@ -9,6 +9,7 @@
extern void synchronize_irq(unsigned int irq);
+extern void synchronize_hardirq(unsigned int irq);
#if defined(CONFIG_TINY_RCU)
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 481a13c43b17..274ba9238fb7 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -32,24 +32,10 @@ static int __init setup_forced_irqthreads(char *arg)
early_param("threadirqs", setup_forced_irqthreads);
#endif
-/**
- * synchronize_irq - wait for pending IRQ handlers (on other CPUs)
- * @irq: interrupt number to wait for
- *
- * This function waits for any pending IRQ handlers for this interrupt
- * to complete before returning. If you use this function while
- * holding a resource the IRQ handler may need you will deadlock.
- *
- * This function may be called - with care - from IRQ context.
- */
-void synchronize_irq(unsigned int irq)
+static void __synchronize_hardirq(struct irq_desc *desc)
{
- struct irq_desc *desc = irq_to_desc(irq);
bool inprogress;
- if (!desc)
- return;
-
do {
unsigned long flags;
@@ -67,12 +53,56 @@ void synchronize_irq(unsigned int irq)
/* Oops, that failed? */
} while (inprogress);
+}
- /*
- * We made sure that no hardirq handler is running. Now verify
- * that no threaded handlers are active.
- */
- wait_event(desc->wait_for_threads, !atomic_read(&desc->threads_active));
+/**
+ * synchronize_hardirq - wait for pending hard IRQ handlers (on other CPUs)
+ * @irq: interrupt number to wait for
+ *
+ * This function waits for any pending hard IRQ handlers for this
+ * interrupt to complete before returning. If you use this
+ * function while holding a resource the IRQ handler may need you
+ * will deadlock. It does not take associated threaded handlers
+ * into account.
+ *
+ * Do not use this for shutdown scenarios where you must be sure
+ * that all parts (hardirq and threaded handler) have completed.
+ *
+ * This function may be called - with care - from IRQ context.
+ */
+void synchronize_hardirq(unsigned int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ if (desc)
+ __synchronize_hardirq(desc);
+}
+EXPORT_SYMBOL(synchronize_hardirq);
+
+/**
+ * synchronize_irq - wait for pending IRQ handlers (on other CPUs)
+ * @irq: interrupt number to wait for
+ *
+ * This function waits for any pending IRQ handlers for this interrupt
+ * to complete before returning. If you use this function while
+ * holding a resource the IRQ handler may need you will deadlock.
+ *
+ * This function may be called - with care - from IRQ context.
+ */
+void synchronize_irq(unsigned int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ if (desc) {
+ __synchronize_hardirq(desc);
+ /*
+ * We made sure that no hardirq handler is
+ * running. Now verify that no threaded handlers are
+ * active.
+ */
+ wait_event(desc->wait_for_threads,
+ !atomic_read(&desc->threads_active));
+ }
}
EXPORT_SYMBOL(synchronize_irq);