From d7e9629de051bb4b1d104588cd97673ad770809e Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 3 Jul 2006 00:24:27 -0700 Subject: [PATCH] [PATCH] lockdep: add local_irq_enable_in_hardirq() API Introduce local_irq_enable_in_hardirq() API. It is currently aliased to local_irq_enable(), hence has no functional effects. This API will be used by lockdep, but even without lockdep this will better document places in the kernel where a hardirq context enables hardirqs. Signed-off-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/interrupt.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 2c5452c1d7bb..73463fbb38e4 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -80,6 +80,23 @@ extern int request_irq(unsigned int, unsigned long, const char *, void *); extern void free_irq(unsigned int, void *); +/* + * On lockdep we dont want to enable hardirqs in hardirq + * context. Use local_irq_enable_in_hardirq() to annotate + * kernel code that has to do this nevertheless (pretty much + * the only valid case is for old/broken hardware that is + * insanely slow). + * + * NOTE: in theory this might break fragile code that relies + * on hardirq delivery - in practice we dont seem to have such + * places left. So the only effect should be slightly increased + * irqs-off latencies. + */ +#ifdef CONFIG_LOCKDEP +# define local_irq_enable_in_hardirq() do { } while (0) +#else +# define local_irq_enable_in_hardirq() local_irq_enable() +#endif #ifdef CONFIG_GENERIC_HARDIRQS extern void disable_irq_nosync(unsigned int irq); -- GitLab