Re: [PATCH 1/4] mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC

2017-04-07 Thread Vlastimil Babka
On 04/05/2017 01:40 PM, Andrey Ryabinin wrote: > On 04/05/2017 10:46 AM, Vlastimil Babka wrote: >> The function __alloc_pages_direct_compact() sets PF_MEMALLOC to prevent >> deadlock during page migration by lock_page() (see the comment in >> __unmap_and_move()). Then it unconditionally clears the

Re: [PATCH 1/4] mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC

2017-04-07 Thread Hillf Danton
On April 05, 2017 3:47 PM Vlastimil Babka wrote: > > The function __alloc_pages_direct_compact() sets PF_MEMALLOC to prevent > deadlock during page migration by lock_page() (see the comment in > __unmap_and_move()). Then it unconditionally clears the flag, which can clear > a > pre-existing PF_M

Re: [PATCH 1/4] mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC

2017-04-05 Thread Andrey Ryabinin
On 04/05/2017 10:46 AM, Vlastimil Babka wrote: > The function __alloc_pages_direct_compact() sets PF_MEMALLOC to prevent > deadlock during page migration by lock_page() (see the comment in > __unmap_and_move()). Then it unconditionally clears the flag, which can clear > a > pre-existing PF_MEMALLO

Re: [PATCH 1/4] mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC

2017-04-05 Thread Michal Hocko
On Wed 05-04-17 09:46:57, Vlastimil Babka wrote: > The function __alloc_pages_direct_compact() sets PF_MEMALLOC to prevent > deadlock during page migration by lock_page() (see the comment in > __unmap_and_move()). Then it unconditionally clears the flag, which can clear > a > pre-existing PF_MEMAL

[PATCH 1/4] mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC

2017-04-05 Thread Vlastimil Babka
The function __alloc_pages_direct_compact() sets PF_MEMALLOC to prevent deadlock during page migration by lock_page() (see the comment in __unmap_and_move()). Then it unconditionally clears the flag, which can clear a pre-existing PF_MEMALLOC flag and result in recursive reclaim. This was not a pro