| Message ID | 20200403112928.19742-4-kirill.shutemov@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | thp/khugepaged improvements and CoW semantics | expand |
On 4/3/20 4:29 AM, Kirill A. Shutemov wrote: > Having a page in LRU add cache offsets page refcount and gives > false-negative on PageLRU(). It reduces collapse success rate. > > Drain all LRU add caches before scanning. It happens relatively > rare and should not disturb the system too much. > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Yang Shi <yang.shi@linux.alibaba.com> > --- > mm/khugepaged.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index 14d7afc90786..fdc10ffde1ca 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c > @@ -2065,6 +2065,8 @@ static void khugepaged_do_scan(void) > > barrier(); /* write khugepaged_pages_to_scan to local stack */ > > + lru_add_drain_all(); > + > while (progress < pages) { > if (!khugepaged_prealloc_page(&hpage, &wait)) > break;
diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 14d7afc90786..fdc10ffde1ca 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -2065,6 +2065,8 @@ static void khugepaged_do_scan(void) barrier(); /* write khugepaged_pages_to_scan to local stack */ + lru_add_drain_all(); + while (progress < pages) { if (!khugepaged_prealloc_page(&hpage, &wait)) break;
Having a page in LRU add cache offsets page refcount and gives false-negative on PageLRU(). It reduces collapse success rate. Drain all LRU add caches before scanning. It happens relatively rare and should not disturb the system too much. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> --- mm/khugepaged.c | 2 ++ 1 file changed, 2 insertions(+)