On Tue, 8 Dec 2015 11:39:50 -0800 Yang Shi <[email protected]> wrote:
> For slow version, just add trace point for raw __get_user_pages since all > slow variants call it to do the real work finally. > > Signed-off-by: Yang Shi <[email protected]> > --- > mm/gup.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/mm/gup.c b/mm/gup.c > index deafa2c..44f05c9 100644 > --- a/mm/gup.c > +++ b/mm/gup.c > @@ -18,6 +18,9 @@ > > #include "internal.h" > > +#define CREATE_TRACE_POINTS > +#include <trace/events/gup.h> > + > static struct page *no_page_table(struct vm_area_struct *vma, > unsigned int flags) > { > @@ -462,6 +465,8 @@ long __get_user_pages(struct task_struct *tsk, struct > mm_struct *mm, > if (!nr_pages) > return 0; > > + trace_gup_get_user_pages(start, nr_pages); > + > VM_BUG_ON(!!pages != !!(gup_flags & FOLL_GET)); > > /* > @@ -599,6 +604,7 @@ int fixup_user_fault(struct task_struct *tsk, struct > mm_struct *mm, > if (!(vm_flags & vma->vm_flags)) > return -EFAULT; > > + trace_gup_fixup_user_fault(address); > ret = handle_mm_fault(mm, vma, address, fault_flags); > if (ret & VM_FAULT_ERROR) { > if (ret & VM_FAULT_OOM) > @@ -1340,6 +1346,8 @@ int __get_user_pages_fast(unsigned long start, int > nr_pages, int write, > start, len))) > return 0; > > + trace_gup_get_user_pages_fast(start, (unsigned long) nr_pages); typecast shouldn't be needed. But I'm wondering, it would save space in the ring buffer if we used unsigend int instead of long. Will nr_pages ever be bigger than 4 billion? -- Steve > + > /* > * Disable interrupts. We use the nested form as we can already have > * interrupts disabled by get_futex_key. -- 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/
