Merge tag 'v4.0-rc2' into irq/core, to refresh the tree before applying new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
index cba442e..f4af034 100644
--- a/include/linux/hardirq.h
+++ b/include/linux/hardirq.h
@@ -9,7 +9,7 @@
extern void synchronize_irq(unsigned int irq);
-extern void synchronize_hardirq(unsigned int irq);
+extern bool synchronize_hardirq(unsigned int irq);
#if defined(CONFIG_TINY_RCU)
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index d9b05b5..3bb01b9 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -184,6 +184,7 @@
#endif
extern void disable_irq_nosync(unsigned int irq);
+extern bool disable_hardirq(unsigned int irq);
extern void disable_irq(unsigned int irq);
extern void disable_percpu_irq(unsigned int irq);
extern void enable_irq(unsigned int irq);
diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h
index d176d65..5dd1272 100644
--- a/include/linux/irqflags.h
+++ b/include/linux/irqflags.h
@@ -85,7 +85,7 @@
* The local_irq_*() APIs are equal to the raw_local_irq*()
* if !TRACE_IRQFLAGS.
*/
-#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
+#ifdef CONFIG_TRACE_IRQFLAGS
#define local_irq_enable() \
do { trace_hardirqs_on(); raw_local_irq_enable(); } while (0)
#define local_irq_disable() \
@@ -107,22 +107,6 @@
raw_local_irq_restore(flags); \
} \
} while (0)
-#define local_save_flags(flags) \
- do { \
- raw_local_save_flags(flags); \
- } while (0)
-
-#define irqs_disabled_flags(flags) \
- ({ \
- raw_irqs_disabled_flags(flags); \
- })
-
-#define irqs_disabled() \
- ({ \
- unsigned long _flags; \
- raw_local_save_flags(_flags); \
- raw_irqs_disabled_flags(_flags); \
- })
#define safe_halt() \
do { \
@@ -131,7 +115,7 @@
} while (0)
-#else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */
+#else /* !CONFIG_TRACE_IRQFLAGS */
#define local_irq_enable() do { raw_local_irq_enable(); } while (0)
#define local_irq_disable() do { raw_local_irq_disable(); } while (0)
@@ -140,11 +124,28 @@
raw_local_irq_save(flags); \
} while (0)
#define local_irq_restore(flags) do { raw_local_irq_restore(flags); } while (0)
-#define local_save_flags(flags) do { raw_local_save_flags(flags); } while (0)
-#define irqs_disabled() (raw_irqs_disabled())
-#define irqs_disabled_flags(flags) (raw_irqs_disabled_flags(flags))
#define safe_halt() do { raw_safe_halt(); } while (0)
+#endif /* CONFIG_TRACE_IRQFLAGS */
+
+#define local_save_flags(flags) raw_local_save_flags(flags)
+
+/*
+ * Some architectures don't define arch_irqs_disabled(), so even if either
+ * definition would be fine we need to use different ones for the time being
+ * to avoid build issues.
+ */
+#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
+#define irqs_disabled() \
+ ({ \
+ unsigned long _flags; \
+ raw_local_save_flags(_flags); \
+ raw_irqs_disabled_flags(_flags); \
+ })
+#else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */
+#define irqs_disabled() raw_irqs_disabled()
#endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */
+#define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
+
#endif
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 196a06f..03329c2 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -68,14 +68,20 @@
* Do not use this for shutdown scenarios where you must be sure
* that all parts (hardirq and threaded handler) have completed.
*
+ * Returns: false if a threaded handler is active.
+ *
* This function may be called - with care - from IRQ context.
*/
-void synchronize_hardirq(unsigned int irq)
+bool synchronize_hardirq(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
- if (desc)
+ if (desc) {
__synchronize_hardirq(desc);
+ return !atomic_read(&desc->threads_active);
+ }
+
+ return true;
}
EXPORT_SYMBOL(synchronize_hardirq);
@@ -440,6 +446,32 @@
}
EXPORT_SYMBOL(disable_irq);
+/**
+ * disable_hardirq - disables an irq and waits for hardirq completion
+ * @irq: Interrupt to disable
+ *
+ * Disable the selected interrupt line. Enables and Disables are
+ * nested.
+ * 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 hard IRQ handler may need you will deadlock.
+ *
+ * When used to optimistically disable an interrupt from atomic context
+ * the return value must be checked.
+ *
+ * Returns: false if a threaded handler is active.
+ *
+ * This function may be called - with care - from IRQ context.
+ */
+bool disable_hardirq(unsigned int irq)
+{
+ if (!__disable_irq_nosync(irq))
+ return synchronize_hardirq(irq);
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(disable_hardirq);
+
void __enable_irq(struct irq_desc *desc, unsigned int irq)
{
switch (desc->depth) {