diff options
Diffstat (limited to 'mm')
-rw-r--r-- | mm/swap_state.c | 27 |
1 files changed, 8 insertions, 19 deletions
diff --git a/mm/swap_state.c b/mm/swap_state.c index a063a902ed0..4f251775ef9 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -143,7 +143,6 @@ void __delete_from_swap_cache(struct page *page) int add_to_swap(struct page * page) { swp_entry_t entry; - int pf_flags; int err; if (!PageLocked(page)) @@ -154,29 +153,19 @@ int add_to_swap(struct page * page) if (!entry.val) return 0; - /* Radix-tree node allocations are performing - * GFP_ATOMIC allocations under PF_MEMALLOC. - * They can completely exhaust the page allocator. - * - * So PF_MEMALLOC is dropped here. This causes the slab - * allocations to fail earlier, so radix-tree nodes will - * then be allocated from the mempool reserves. + /* + * Radix-tree node allocations from PF_MEMALLOC contexts could + * completely exhaust the page allocator. __GFP_NOMEMALLOC + * stops emergency reserves from being allocated. * - * We're still using __GFP_HIGH for radix-tree node - * allocations, so some of the emergency pools are available, - * just not all of them. + * TODO: this could cause a theoretical memory reclaim + * deadlock in the swap out path. */ - - pf_flags = current->flags; - current->flags &= ~PF_MEMALLOC; - /* * Add it to the swap cache and mark it dirty */ - err = __add_to_swap_cache(page, entry, GFP_ATOMIC|__GFP_NOWARN); - - if (pf_flags & PF_MEMALLOC) - current->flags |= PF_MEMALLOC; + err = __add_to_swap_cache(page, entry, + GFP_ATOMIC|__GFP_NOMEMALLOC|__GFP_NOWARN); switch (err) { case 0: /* Success */ |