Re: [PATCH v3 6/9] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-30 Thread Joonsoo Kim
On Tue, Jul 30, 2013 at 08:37:08AM +1000, David Gibson wrote: > On Mon, Jul 29, 2013 at 02:28:18PM +0900, Joonsoo Kim wrote: > > Currently, we use a page with mapped count 1 in page cache for cow > > optimization. If we find this condition, we don't allocate a new > > page and copy contents.

Re: [PATCH v3 6/9] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-30 Thread Joonsoo Kim
On Tue, Jul 30, 2013 at 08:37:08AM +1000, David Gibson wrote: On Mon, Jul 29, 2013 at 02:28:18PM +0900, Joonsoo Kim wrote: Currently, we use a page with mapped count 1 in page cache for cow optimization. If we find this condition, we don't allocate a new page and copy contents. Instead, we

Re: [PATCH v3 6/9] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-29 Thread David Gibson
On Mon, Jul 29, 2013 at 02:28:18PM +0900, Joonsoo Kim wrote: > Currently, we use a page with mapped count 1 in page cache for cow > optimization. If we find this condition, we don't allocate a new > page and copy contents. Instead, we map this page directly. > This may introduce a problem that

Re: [PATCH v3 6/9] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-29 Thread Hillf Danton
On Mon, Jul 29, 2013 at 1:28 PM, Joonsoo Kim wrote: > Currently, we use a page with mapped count 1 in page cache for cow > optimization. If we find this condition, we don't allocate a new > page and copy contents. Instead, we map this page directly. > This may introduce a problem that writting to

Re: [PATCH v3 6/9] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-29 Thread Hillf Danton
On Mon, Jul 29, 2013 at 1:28 PM, Joonsoo Kim iamjoonsoo@lge.com wrote: Currently, we use a page with mapped count 1 in page cache for cow optimization. If we find this condition, we don't allocate a new page and copy contents. Instead, we map this page directly. This may introduce a

Re: [PATCH v3 6/9] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-29 Thread David Gibson
On Mon, Jul 29, 2013 at 02:28:18PM +0900, Joonsoo Kim wrote: Currently, we use a page with mapped count 1 in page cache for cow optimization. If we find this condition, we don't allocate a new page and copy contents. Instead, we map this page directly. This may introduce a problem that

[PATCH v3 6/9] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-28 Thread Joonsoo Kim
Currently, we use a page with mapped count 1 in page cache for cow optimization. If we find this condition, we don't allocate a new page and copy contents. Instead, we map this page directly. This may introduce a problem that writting to private mapping overwrite hugetlb file directly. You can

[PATCH v3 6/9] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-28 Thread Joonsoo Kim
Currently, we use a page with mapped count 1 in page cache for cow optimization. If we find this condition, we don't allocate a new page and copy contents. Instead, we map this page directly. This may introduce a problem that writting to private mapping overwrite hugetlb file directly. You can