Hi Christian, On 04/03/2013 06:40 PM, Christian Ruppert wrote: > This patch adds implicit memory barriers to irqsave/restore functions of > the ARC architecture port in line with what is done in other architectures. > > It seems to fix several seemingly unrelated issues in our platform but for > the moment it is insufficiently tested (and might even be incomplete). > Please comment.
I think this is not needed. Semantically we need barrier for spinlocks, not irq save/restore - although spin locks are one of the primary users of irq save/restore API. So repeating what Thomas already said, the barrier already exists for PREEMPT_COUNT, we need to make sure they are present for !PREEMPT_COUNT. -Vineet > Signed-off-by: Christian Ruppert <christian.rupp...@abilis.com> > --- > arch/arc/include/asm/irqflags.h | 8 ++++---- > 1 files changed, 4 insertions(+), 4 deletions(-) > > diff --git a/arch/arc/include/asm/irqflags.h b/arch/arc/include/asm/irqflags.h > index ccd8480..c8147d1 100644 > --- a/arch/arc/include/asm/irqflags.h > +++ b/arch/arc/include/asm/irqflags.h > @@ -39,7 +39,7 @@ static inline long arch_local_irq_save(void) > " flag.nz %0 \n" > : "=r"(temp), "=r"(flags) > : "n"((STATUS_E1_MASK | STATUS_E2_MASK)) > - : "cc"); > + : "memory", "cc"); > > return flags; > } > @@ -53,7 +53,7 @@ static inline void arch_local_irq_restore(unsigned long > flags) > __asm__ __volatile__( > " flag %0 \n" > : > - : "r"(flags)); > + : "r"(flags) : "memory"); > } > > /* > @@ -73,7 +73,7 @@ static inline void arch_local_irq_disable(void) > " and %0, %0, %1 \n" > " flag %0 \n" > : "=&r"(temp) > - : "n"(~(STATUS_E1_MASK | STATUS_E2_MASK))); > + : "n"(~(STATUS_E1_MASK | STATUS_E2_MASK)) : "memory"); > } > > /* > @@ -85,7 +85,7 @@ static inline long arch_local_save_flags(void) > > __asm__ __volatile__( > " lr %0, [status32] \n" > - : "=&r"(temp)); > + : "=&r"(temp) : : "memory"); > > return temp; > } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
