[added to the 4.1 stable tree] genirq: Provide irq_gc_{lock_irqsave,unlock_irqrestore}() helpers

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>

This patch has been added to the 4.1 stable tree. If you have any
objections, please let us know.

===============

[ Upstream commit ebf9ff753c041b296241990aef76163bbb2cc9c8 ]

Some irqchip drivers need to take the generic chip lock outside of the
irq context.

Provide the irq_gc_{lock_irqsave,unlock_irqrestore}() helpers to allow
one to disable irqs while entering a critical section protected by
gc->lock.

Note that we do not provide optimized version of these helpers for !SMP,
because they are not called from the hot-path.

[ tglx: Added a comment when these helpers should be [not] used ]

Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
Cc: Jason Cooper <jason@xxxxxxxxxxxxxx>
Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
Cc: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Cc: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1473775109-4192-1-git-send-email-boris.brezillon@xxxxxxxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
 include/linux/irq.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index 3532dca..33475a3 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -852,6 +852,16 @@ static inline void irq_gc_lock(struct irq_chip_generic *gc) { }
 static inline void irq_gc_unlock(struct irq_chip_generic *gc) { }
 #endif
 
+/*
+ * The irqsave variants are for usage in non interrupt code. Do not use
+ * them in irq_chip callbacks. Use irq_gc_lock() instead.
+ */
+#define irq_gc_lock_irqsave(gc, flags)	\
+	raw_spin_lock_irqsave(&(gc)->lock, flags)
+
+#define irq_gc_unlock_irqrestore(gc, flags)	\
+	raw_spin_unlock_irqrestore(&(gc)->lock, flags)
+
 static inline void irq_reg_writel(struct irq_chip_generic *gc,
 				  u32 val, int reg_offset)
 {
-- 
2.7.4
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]