From 8bc719d3cab8414938f9ea6e33b58d8810d18068 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Mon, 25 Sep 2006 23:31:20 -0700 Subject: [PATCH] out of memory notifier Add a notifer chain to the out of memory killer. If one of the registered callbacks could release some memory, do not kill the process but return and retry the allocation that forced the oom killer to run. The purpose of the notifier is to add a safety net in the presence of memory ballooners. If the resource manager inflated the balloon to a size where memory allocations can not be satisfied anymore, it is better to deflate the balloon a bit instead of killing processes. The implementation for the s390 ballooner is included. [akpm@osdl.org: cleanups] Signed-off-by: Martin Schwidefsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/swap.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include') diff --git a/include/linux/swap.h b/include/linux/swap.h index 34a6bc3e6cf..32db06c8ffe 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -10,6 +10,8 @@ #include #include +struct notifier_block; + #define SWAP_FLAG_PREFER 0x8000 /* set if swap priority specified */ #define SWAP_FLAG_PRIO_MASK 0x7fff #define SWAP_FLAG_PRIO_SHIFT 0 @@ -156,6 +158,8 @@ struct swap_list_t { /* linux/mm/oom_kill.c */ extern void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order); +extern int register_oom_notifier(struct notifier_block *nb); +extern int unregister_oom_notifier(struct notifier_block *nb); /* linux/mm/memory.c */ extern void swapin_readahead(swp_entry_t, unsigned long, struct vm_area_struct *); -- cgit v1.2.3