| Message ID | 20190404054828.2731-1-sjhuang@iluvatar.ai (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mm:rmap: use the pra.mapcount to do the check | expand |
On 4/3/19 10:48 PM, Huang Shijie wrote: > We have the pra.mapcount already, and there is no need to call > the page_mapped() which may do some complicated computing > for compound page. > > Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai> This looks good to me. I had to convince myself that there were no issues if we were operating on a sub-page of a compound-page. However, Kirill is the expert here and would know of any subtle issues I may have overlooked.
On Thu, 4 Apr 2019 16:08:33 -0700 Mike Kravetz <mike.kravetz@oracle.com> wrote: > On 4/3/19 10:48 PM, Huang Shijie wrote: > > We have the pra.mapcount already, and there is no need to call > > the page_mapped() which may do some complicated computing > > for compound page. > > > > Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai> > > This looks good to me. I had to convince myself that there were no > issues if we were operating on a sub-page of a compound-page. However, > Kirill is the expert here and would know of any subtle issues I may have > overlooked. > > -- > Mike Kravetz > > > --- > > mm/rmap.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/mm/rmap.c b/mm/rmap.c > > index 76c8dfd3ae1c..6c5843dddb5a 100644 > > --- a/mm/rmap.c > > +++ b/mm/rmap.c > > @@ -850,7 +850,7 @@ int page_referenced(struct page *page, > > }; > > > > *vm_flags = 0; > > - if (!page_mapped(page)) > > + if (!pra.mapcount) > > return 0; > > > > if (!page_rmapping(page)) > >
On Thu, Apr 04, 2019 at 11:08:33PM +0000, Mike Kravetz wrote: > On 4/3/19 10:48 PM, Huang Shijie wrote: > > We have the pra.mapcount already, and there is no need to call > > the page_mapped() which may do some complicated computing > > for compound page. > > > > Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai> > > This looks good to me. I had to convince myself that there were no > issues if we were operating on a sub-page of a compound-page. However, > Kirill is the expert here and would know of any subtle issues I may have > overlooked. Looks good to me. Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
diff --git a/mm/rmap.c b/mm/rmap.c index 76c8dfd3ae1c..6c5843dddb5a 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -850,7 +850,7 @@ int page_referenced(struct page *page, }; *vm_flags = 0; - if (!page_mapped(page)) + if (!pra.mapcount) return 0; if (!page_rmapping(page))
We have the pra.mapcount already, and there is no need to call the page_mapped() which may do some complicated computing for compound page. Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai> --- mm/rmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)