mm, oom: pass an oom order of -1 when triggered by sysrq

[cascardo/linux.git] / mm / memcontrol.c

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index acb93c5..9871f13 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1545,6 +1545,12 @@ static unsigned long mem_cgroup_get_limit(struct mem_cgroup *memcg)
 static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
                                     int order)
 {
+       struct oom_control oc = {
+               .zonelist = NULL,
+               .nodemask = NULL,
+               .gfp_mask = gfp_mask,
+               .order = order,
+       };
        struct mem_cgroup *iter;
        unsigned long chosen_points = 0;
        unsigned long totalpages;
@@ -1563,7 +1569,7 @@ static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
                goto unlock;
        }
 
-       check_panic_on_oom(CONSTRAINT_MEMCG, gfp_mask, order, NULL, memcg);
+       check_panic_on_oom(&oc, CONSTRAINT_MEMCG, memcg);
        totalpages = mem_cgroup_get_limit(memcg) ? : 1;
        for_each_mem_cgroup_tree(iter, memcg) {
                struct css_task_iter it;
@@ -1571,8 +1577,7 @@ static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
 
                css_task_iter_start(&iter->css, &it);
                while ((task = css_task_iter_next(&it))) {
-                       switch (oom_scan_process_thread(task, totalpages, NULL,
-                                                       false)) {
+                       switch (oom_scan_process_thread(&oc, task, totalpages)) {
                        case OOM_SCAN_SELECT:
                                if (chosen)
                                        put_task_struct(chosen);
@@ -1610,8 +1615,8 @@ static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
 
        if (chosen) {
                points = chosen_points * 1000 / totalpages;
-               oom_kill_process(chosen, gfp_mask, order, points, totalpages,
-                                memcg, NULL, "Memory cgroup out of memory");
+               oom_kill_process(&oc, chosen, points, totalpages, memcg,
+                                "Memory cgroup out of memory");
        }
 unlock:
        mutex_unlock(&oom_lock);
@@ -5965,7 +5970,13 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
        if (!mem_cgroup_is_root(memcg))
                page_counter_uncharge(&memcg->memory, 1);
 
-       /* Caller disabled preemption with mapping->tree_lock */
+       /*
+        * Interrupts should be disabled here because the caller holds the
+        * mapping->tree_lock lock which is taken with interrupts-off. It is
+        * important here to have the interrupts disabled because it is the
+        * only synchronisation we have for udpating the per-CPU variables.
+        */
+       VM_BUG_ON(!irqs_disabled());
        mem_cgroup_charge_statistics(memcg, page, -1);
        memcg_check_events(memcg, page);
 }