On Wed, Oct 01, 2014 at 10:56:34AM +0200, Andrea Arcangeli wrote: > From: Andres Lagar-Cavilla <[email protected]>
This needs a changelog.... > Reviewed-by: Radim Krčmář <[email protected]> > Signed-off-by: Andres Lagar-Cavilla <[email protected]> > Signed-off-by: Andrea Arcangeli <[email protected]> > --- > include/linux/mm.h | 1 + > mm/gup.c | 4 ++++ > 2 files changed, 5 insertions(+) > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 8981cc8..0f4196a 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -1985,6 +1985,7 @@ static inline struct page *follow_page(struct > vm_area_struct *vma, > #define FOLL_HWPOISON 0x100 /* check page is hwpoisoned */ > #define FOLL_NUMA 0x200 /* force NUMA hinting page fault */ > #define FOLL_MIGRATION 0x400 /* wait for page to replace migration > entry */ > +#define FOLL_TRIED 0x800 /* a retry, previous pass started an IO */ > > typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr, > void *data); > diff --git a/mm/gup.c b/mm/gup.c > index 91d044b..af7ea3e 100644 > --- a/mm/gup.c > +++ b/mm/gup.c > @@ -281,6 +281,10 @@ static int faultin_page(struct task_struct *tsk, struct > vm_area_struct *vma, > fault_flags |= FAULT_FLAG_ALLOW_RETRY; > if (*flags & FOLL_NOWAIT) > fault_flags |= FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_RETRY_NOWAIT; > + if (*flags & FOLL_TRIED) { > + VM_WARN_ON_ONCE(fault_flags & FAULT_FLAG_ALLOW_RETRY); > + fault_flags |= FAULT_FLAG_TRIED; > + } > > ret = handle_mm_fault(mm, vma, address, fault_flags); > if (ret & VM_FAULT_ERROR) { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
