From f948501b36c6b3d9352ce212a197098a7e958971 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Fri, 15 Jun 2012 14:51:39 +1000 Subject: Make hard_irq_disable() actually hard-disable interrupts At present, hard_irq_disable() does nothing on powerpc because of this code in include/linux/interrupt.h: #ifndef hard_irq_disable #define hard_irq_disable() do { } while(0) #endif So we need to make our hard_irq_disable be a macro. It was previously a macro until commit 7230c56441 ("powerpc: Rework lazy-interrupt handling") changed it to a static inline function. Cc: stable@vger.kernel.org Acked-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras -- arch/powerpc/include/asm/hw_irq.h | 3 +++ 1 file changed, 3 insertions(+) --- arch/powerpc/include/asm/hw_irq.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch/powerpc/include/asm/hw_irq.h') diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm/hw_irq.h index c9aac24b02e2..32b394f3b854 100644 --- a/arch/powerpc/include/asm/hw_irq.h +++ b/arch/powerpc/include/asm/hw_irq.h @@ -100,6 +100,9 @@ static inline void hard_irq_disable(void) get_paca()->irq_happened |= PACA_IRQ_HARD_DIS; } +/* include/linux/interrupt.h needs hard_irq_disable to be a macro */ +#define hard_irq_disable hard_irq_disable + /* * This is called by asynchronous interrupts to conditionally * re-enable hard interrupts when soft-disabled after having -- cgit v1.2.3 From 0b17ba7258db83cd02da560884e053b85de371f2 Mon Sep 17 00:00:00 2001 From: Anton Blanchard Date: Wed, 27 Jun 2012 13:13:52 +0000 Subject: powerpc: check_and_cede_processor() never cedes Commit f948501b36c6 ("Make hard_irq_disable() actually hard-disable interrupts") caused check_and_cede_processor to stop working. ->irq_happened will never be zero right after a hard_irq_disable so the compiler removes the call to cede_processor completely. The bug was introduced back in the lazy interrupt handling rework of 3.4 but was hidden until recently because hard_irq_disable did nothing. This issue will eventually appear in 3.4 stable since the hard_irq_disable fix is marked stable, so mark this one for stable too. Signed-off-by: Anton Blanchard Cc: stable@vger.kernel.org Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/hw_irq.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/powerpc/include/asm/hw_irq.h') diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm/hw_irq.h index 32b394f3b854..6eb75b80488c 100644 --- a/arch/powerpc/include/asm/hw_irq.h +++ b/arch/powerpc/include/asm/hw_irq.h @@ -103,6 +103,11 @@ static inline void hard_irq_disable(void) /* include/linux/interrupt.h needs hard_irq_disable to be a macro */ #define hard_irq_disable hard_irq_disable +static inline bool lazy_irq_pending(void) +{ + return !!(get_paca()->irq_happened & ~PACA_IRQ_HARD_DIS); +} + /* * This is called by asynchronous interrupts to conditionally * re-enable hard interrupts when soft-disabled after having -- cgit v1.2.3