mm, oom: ensure memoryless node zonelist always includes zones

With memoryless node support being worked on, it's possible that for
optimizations that a node may not have a non-NULL zonelist.  When
CONFIG_NUMA is enabled and node 0 is memoryless, this means the zonelist
for first_online_node may become NULL.

The oom killer requires a zonelist that includes all memory zones for
the sysrq trigger and pagefault out of memory handler.

Ensure that a non-NULL zonelist is always passed to the oom killer.

[akpm@linux-foundation.org: fix non-numa build]
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Rientjes 2014-08-06 16:07:50 -07:00 committed by Linus Torvalds
parent 6e90b58be7
commit 8d060bf490
3 changed files with 12 additions and 3 deletions

View file

@ -355,7 +355,7 @@ static struct sysrq_key_op sysrq_term_op = {
static void moom_callback(struct work_struct *ignored)
{
out_of_memory(node_zonelist(first_online_node, GFP_KERNEL), GFP_KERNEL,
out_of_memory(node_zonelist(first_memory_node, GFP_KERNEL), GFP_KERNEL,
0, NULL, true);
}

View file

@ -430,7 +430,15 @@ static inline int num_node_state(enum node_states state)
for_each_node_mask((__node), node_states[__state])
#define first_online_node first_node(node_states[N_ONLINE])
#define next_online_node(nid) next_node((nid), node_states[N_ONLINE])
#define first_memory_node first_node(node_states[N_MEMORY])
static inline int next_online_node(int nid)
{
return next_node(nid, node_states[N_ONLINE]);
}
static inline int next_memory_node(int nid)
{
return next_node(nid, node_states[N_MEMORY]);
}
extern int nr_node_ids;
extern int nr_online_nodes;
@ -471,6 +479,7 @@ static inline int num_node_state(enum node_states state)
for ( (node) = 0; (node) == 0; (node) = 1)
#define first_online_node 0
#define first_memory_node 0
#define next_online_node(nid) (MAX_NUMNODES)
#define nr_node_ids 1
#define nr_online_nodes 1

View file

@ -694,7 +694,7 @@ void pagefault_out_of_memory(void)
if (mem_cgroup_oom_synchronize(true))
return;
zonelist = node_zonelist(first_online_node, GFP_KERNEL);
zonelist = node_zonelist(first_memory_node, GFP_KERNEL);
if (try_set_zonelist_oom(zonelist, GFP_KERNEL)) {
out_of_memory(NULL, 0, 0, NULL, false);
clear_zonelist_oom(zonelist, GFP_KERNEL);