From e82a3b75127188f20c7780bec580e148beb29da7 Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Tue, 16 Jun 2009 20:51:48 +0000 Subject: parisc: ensure broadcast tlb purge runs single threaded The TLB flushing functions on hppa, which causes PxTLB broadcasts on the system bus, needs to be protected by irq-safe spinlocks to avoid irq handlers to deadlock the kernel. The deadlocks only happened during I/O intensive loads and triggered pretty seldom, which is why this bug went so long unnoticed. Signed-off-by: Helge Deller [edited to use spin_lock_irqsave on UP as well since we'd been locking there all this time anyway, --kyle] Signed-off-by: Kyle McMartin --- arch/parisc/include/asm/tlbflush.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'arch/parisc/include/asm') diff --git a/arch/parisc/include/asm/tlbflush.h b/arch/parisc/include/asm/tlbflush.h index 1f6fd4fc05b..8f1a8100bf2 100644 --- a/arch/parisc/include/asm/tlbflush.h +++ b/arch/parisc/include/asm/tlbflush.h @@ -12,14 +12,12 @@ * N class systems, only one PxTLB inter processor broadcast can be * active at any one time on the Merced bus. This tlb purge * synchronisation is fairly lightweight and harmless so we activate - * it on all SMP systems not just the N class. We also need to have - * preemption disabled on uniprocessor machines, and spin_lock does that - * nicely. + * it on all systems not just the N class. */ extern spinlock_t pa_tlb_lock; -#define purge_tlb_start(x) spin_lock(&pa_tlb_lock) -#define purge_tlb_end(x) spin_unlock(&pa_tlb_lock) +#define purge_tlb_start(flags) spin_lock_irqsave(&pa_tlb_lock, flags) +#define purge_tlb_end(flags) spin_unlock_irqrestore(&pa_tlb_lock, flags) extern void flush_tlb_all(void); extern void flush_tlb_all_local(void *); @@ -63,14 +61,16 @@ static inline void flush_tlb_mm(struct mm_struct *mm) static inline void flush_tlb_page(struct vm_area_struct *vma, unsigned long addr) { + unsigned long flags; + /* For one page, it's not worth testing the split_tlb variable */ mb(); mtsp(vma->vm_mm->context,1); - purge_tlb_start(); + purge_tlb_start(flags); pdtlb(addr); pitlb(addr); - purge_tlb_end(); + purge_tlb_end(flags); } void __flush_tlb_range(unsigned long sid, -- cgit v1.2.3