From 9b0f8b040acd8dfd23860754c0d09ff4f44e2cbc Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Mon, 20 Feb 2006 18:27:52 -0800 Subject: [PATCH] Terminate process that fails on a constrained allocation Some allocations are restricted to a limited set of nodes (due to memory policies or cpuset constraints). If the page allocator is not able to find enough memory then that does not mean that overall system memory is low. In particular going postal and more or less randomly shooting at processes is not likely going to help the situation but may just lead to suicide (the whole system coming down). It is better to signal to the process that no memory exists given the constraints that the process (or the configuration of the process) has placed on the allocation behavior. The process may be killed but then the sysadmin or developer can investigate the situation. The solution is similar to what we do when running out of hugepages. This patch adds a check before we kill processes. At that point performance considerations do not matter much so we just scan the zonelist and reconstruct a list of nodes. If the list of nodes does not contain all online nodes then this is a constrained allocation and we should kill the current process. Signed-off-by: Christoph Lameter Cc: Nick Piggin Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/char/sysrq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/char/sysrq.c') diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c index 5765f67..d58f823 100644 --- a/drivers/char/sysrq.c +++ b/drivers/char/sysrq.c @@ -243,7 +243,7 @@ static struct sysrq_key_op sysrq_term_op = { static void moom_callback(void *ignored) { - out_of_memory(GFP_KERNEL, 0); + out_of_memory(&NODE_DATA(0)->node_zonelists[ZONE_NORMAL], GFP_KERNEL, 0); } static DECLARE_WORK(moom_work, moom_callback, NULL); -- cgit v1.1