[PATCH 4.16 55/64] genirq/migration: Avoid out of line call if pending is not set

[Greg Kroah-Hartman]

4.16-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

commit d340ebd696f921d3ad01b8c0c29dd38f2ad2bf3e upstream.

The upcoming fix for the -EBUSY return from affinity settings requires to
use the irq_move_irq() functionality even on irq remapped interrupts. To
avoid the out of line call, move the check for the pending bit into an
inline helper.

Preparatory change for the real fix. No functional change.

Fixes: dccfe3147b42 ("x86/vector: Simplify vector move cleanup")
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Joerg Roedel <jroedel@xxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Song Liu <liu.song.a23@xxxxxxxxx>
Cc: Dmitry Safonov <0x7f454c46@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Cc: Mike Travis <mike.travis@xxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Tariq Toukan <tariqt@xxxxxxxxxxxx>
Cc: Dou Liyang <douly.fnst@xxxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20180604162224.471925894@xxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 include/linux/irq.h    |    7 ++++++-
 kernel/irq/migration.c |    5 +----
 2 files changed, 7 insertions(+), 5 deletions(-)

--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -556,7 +556,12 @@ extern int irq_affinity_online_cpu(unsig
 #endif
 
 #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_PENDING_IRQ)
-void irq_move_irq(struct irq_data *data);
+void __irq_move_irq(struct irq_data *data);
+static inline void irq_move_irq(struct irq_data *data)
+{
+	if (unlikely(irqd_is_setaffinity_pending(data)))
+		__irq_move_irq(data);
+}
 void irq_move_masked_irq(struct irq_data *data);
 void irq_force_complete_move(struct irq_desc *desc);
 #else
--- a/kernel/irq/migration.c
+++ b/kernel/irq/migration.c
@@ -91,7 +91,7 @@ void irq_move_masked_irq(struct irq_data
 	cpumask_clear(desc->pending_mask);
 }
 
-void irq_move_irq(struct irq_data *idata)
+void __irq_move_irq(struct irq_data *idata)
 {
 	bool masked;
 
@@ -102,9 +102,6 @@ void irq_move_irq(struct irq_data *idata
 	 */
 	idata = irq_desc_get_irq_data(irq_data_to_desc(idata));
 
-	if (likely(!irqd_is_setaffinity_pending(idata)))
-		return;
-
 	if (unlikely(irqd_irq_disabled(idata)))
 		return;