From c01d403b2e3e3f231b18ebd07ad64ecbe6a258a5 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 3 Jul 2006 00:24:27 -0700 Subject: [PATCH] lockdep: add disable/enable_irq_lockdep() API lockdep wants to use the disable_irq()/enable_irq() prototypes before they are provied by the platform's asm/irq.h. So move them out of the CONFIG_GENERIC_HARDIRQS define - all architectures have a common prototype for this anyway. Add special lockdep variants of irq line disabling/enabling. These should be used for locking constructs that know that a particular irq context which is disabled, and which is the only irq-context user of a lock, that it's safe to take the lock in the irq-disabled section without disabling hardirqs. [akpm@osdl.org: build fix] Signed-off-by: Ingo Molnar Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/interrupt.h | 49 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 48 insertions(+), 1 deletion(-) (limited to 'include/linux/interrupt.h') diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index da3e0dbe61d4..2c5452c1d7bb 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -86,6 +86,41 @@ extern void disable_irq_nosync(unsigned int irq); extern void disable_irq(unsigned int irq); extern void enable_irq(unsigned int irq); +/* + * Special lockdep variants of irq disabling/enabling. + * These should be used for locking constructs that + * know that a particular irq context which is disabled, + * and which is the only irq-context user of a lock, + * that it's safe to take the lock in the irq-disabled + * section without disabling hardirqs. + * + * On !CONFIG_LOCKDEP they are equivalent to the normal + * irq disable/enable methods. + */ +static inline void disable_irq_nosync_lockdep(unsigned int irq) +{ + disable_irq_nosync(irq); +#ifdef CONFIG_LOCKDEP + local_irq_disable(); +#endif +} + +static inline void disable_irq_lockdep(unsigned int irq) +{ + disable_irq(irq); +#ifdef CONFIG_LOCKDEP + local_irq_disable(); +#endif +} + +static inline void enable_irq_lockdep(unsigned int irq) +{ +#ifdef CONFIG_LOCKDEP + local_irq_enable(); +#endif + enable_irq(irq); +} + /* IRQ wakeup (PM) control: */ extern int set_irq_wake(unsigned int irq, unsigned int on); @@ -99,7 +134,19 @@ static inline int disable_irq_wake(unsigned int irq) return set_irq_wake(irq, 0); } -#endif +#else /* !CONFIG_GENERIC_HARDIRQS */ +/* + * NOTE: non-genirq architectures, if they want to support the lock + * validator need to define the methods below in their asm/irq.h + * files, under an #ifdef CONFIG_LOCKDEP section. + */ +# ifndef CONFIG_LOCKDEP +# define disable_irq_nosync_lockdep(irq) disable_irq_nosync(irq) +# define disable_irq_lockdep(irq) disable_irq(irq) +# define enable_irq_lockdep(irq) enable_irq(irq) +# endif + +#endif /* CONFIG_GENERIC_HARDIRQS */ #ifndef __ARCH_SET_SOFTIRQ_PENDING #define set_softirq_pending(x) (local_softirq_pending() = (x)) -- cgit v1.2.3 From d7e9629de051bb4b1d104588cd97673ad770809e Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 3 Jul 2006 00:24:27 -0700 Subject: [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(+) (limited to 'include/linux/interrupt.h') 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); -- cgit v1.2.3 From de30a2b355ea85350ca2f58f3b9bf4e5bc007986 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 3 Jul 2006 00:24:42 -0700 Subject: [PATCH] lockdep: irqtrace subsystem, core Accurate hard-IRQ-flags and softirq-flags state tracing. This allows us to attach extra functionality to IRQ flags on/off events (such as trace-on/off). Signed-off-by: Ingo Molnar Signed-off-by: Arjan van de Ven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/interrupt.h | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) (limited to 'include/linux/interrupt.h') diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 73463fbb38e4..d5afee95fd43 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -199,13 +200,11 @@ static inline void __deprecated save_and_cli(unsigned long *x) #define save_and_cli(x) save_and_cli(&x) #endif /* CONFIG_SMP */ -/* SoftIRQ primitives. */ -#define local_bh_disable() \ - do { add_preempt_count(SOFTIRQ_OFFSET); barrier(); } while (0) -#define __local_bh_enable() \ - do { barrier(); sub_preempt_count(SOFTIRQ_OFFSET); } while (0) - +extern void local_bh_disable(void); +extern void __local_bh_enable(void); +extern void _local_bh_enable(void); extern void local_bh_enable(void); +extern void local_bh_enable_ip(unsigned long ip); /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high frequency threaded job scheduling. For almost all the purposes -- cgit v1.2.3