diff --git a/drivers/staging/android/lowmemorykiller.c b/drivers/staging/android/lowmemorykiller.c
index 42cd93ea..05ebece0 100644
--- a/drivers/staging/android/lowmemorykiller.c
+++ b/drivers/staging/android/lowmemorykiller.c
@@ -29,12 +29,17 @@
*
*/
-#include <linux/module.h>
#include <linux/kernel.h>
+#include <linux/kobject.h>
+#include <linux/memory.h>
+#include <linux/memory_hotplug.h>
#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
#include <linux/oom.h>
#include <linux/sched.h>
-#include <linux/notifier.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
static uint32_t lowmem_debug_level = 2;
static int lowmem_adj[6] = {
@@ -52,8 +57,12 @@ static size_t lowmem_minfree[6] = {
};
static int lowmem_minfree_size = 4;
+static size_t lowmem_minfree_notif_trigger;
+
+static unsigned int offlining;
static struct task_struct *lowmem_deathpending;
-static DEFINE_SPINLOCK(lowmem_deathpending_lock);
+static unsigned long lowmem_deathpending_timeout;
+static struct kobject *lowmem_kobj;
#define lowmem_print(level, x...) \
do { \
@@ -68,29 +77,66 @@ static struct notifier_block task_nb = {
.notifier_call = task_notify_func,
};
-
-static void task_free_fn(struct work_struct *work)
-{
- unsigned long flags;
-
- task_free_unregister(&task_nb);
- spin_lock_irqsave(&lowmem_deathpending_lock, flags);
- lowmem_deathpending = NULL;
- spin_unlock_irqrestore(&lowmem_deathpending_lock, flags);
-}
-static DECLARE_WORK(task_free_work, task_free_fn);
-
static int
task_notify_func(struct notifier_block *self, unsigned long val, void *data)
{
struct task_struct *task = data;
- if (task == lowmem_deathpending) {
- schedule_work(&task_free_work);
- }
+ if (task == lowmem_deathpending)
+ lowmem_deathpending = NULL;
+
return NOTIFY_OK;
}
+#ifdef CONFIG_MEMORY_HOTPLUG
+static int lmk_hotplug_callback(struct notifier_block *self,
+ unsigned long cmd, void *data)
+{
+ switch (cmd) {
+ /* Don't care LMK cases */
+ case MEM_ONLINE:
+ case MEM_OFFLINE:
+ case MEM_CANCEL_ONLINE:
+ case MEM_CANCEL_OFFLINE:
+ case MEM_GOING_ONLINE:
+ offlining = 0;
+ lowmem_print(4, "lmk in normal mode\n");
+ break;
+ /* LMK should account for movable zone */
+ case MEM_GOING_OFFLINE:
+ offlining = 1;
+ lowmem_print(4, "lmk in hotplug mode\n");
+ break;
+ }
+ return NOTIFY_DONE;
+}
+#endif
+
+
+
+static void lowmem_notify_killzone_approach(void);
+
+static inline void get_free_ram(int *other_free, int *other_file)
+{
+ struct zone *zone;
+ *other_free = global_page_state(NR_FREE_PAGES);
+ *other_file = global_page_state(NR_FILE_PAGES) -
+ global_page_state(NR_SHMEM);
+
+ if (offlining) {
+ /* Discount all free space in the section being offlined */
+ for_each_zone(zone) {
+ if (zone_idx(zone) == ZONE_MOVABLE) {
+ *other_free -= zone_page_state(zone,
+ NR_FREE_PAGES);
+ lowmem_print(4, "lowmem_shrink discounted "
+ "%lu pages in movable zone\n",
+ zone_page_state(zone, NR_FREE_PAGES));
+ }
+ }
+ }
+}
+
static int lowmem_shrink(int nr_to_scan, gfp_t gfp_mask)
{
struct task_struct *p;
@@ -102,10 +148,8 @@ static int lowmem_shrink(int nr_to_scan, gfp_t gfp_mask)
int selected_tasksize = 0;
int selected_oom_adj;
int array_size = ARRAY_SIZE(lowmem_adj);
- int other_free = global_page_state(NR_FREE_PAGES);
- int other_file = global_page_state(NR_FILE_PAGES);
- unsigned long flags;
-
+ int other_free;
+ int other_file;
/*
* If we already have a death outstanding, then
* bail out right away; indicating to vmscan
@@ -113,15 +157,24 @@ static int lowmem_shrink(int nr_to_scan, gfp_t gfp_mask)
* this pass.
*
*/
- if (lowmem_deathpending)
+ if (lowmem_deathpending &&
+ time_before_eq(jiffies, lowmem_deathpending_timeout))
return 0;
+ get_free_ram(&other_free, &other_file);
+
+ if (other_free < lowmem_minfree_notif_trigger &&
+ other_file < lowmem_minfree_notif_trigger) {
+ lowmem_notify_killzone_approach();
+ }
+
if (lowmem_adj_size < array_size)
array_size = lowmem_adj_size;
if (lowmem_minfree_size < array_size)
array_size = lowmem_minfree_size;
for (i = 0; i < array_size; i++) {
- if (other_file < lowmem_minfree[i]) {
+ if (other_free < lowmem_minfree[i] &&
+ other_file < lowmem_minfree[i]) {
min_adj = lowmem_adj[i];
break;
}
@@ -176,20 +229,14 @@ static int lowmem_shrink(int nr_to_scan, gfp_t gfp_mask)
lowmem_print(2, "select %d (%s), adj %d, size %d, to kill\n",
p->pid, p->comm, oom_adj, tasksize);
}
-
if (selected) {
- spin_lock_irqsave(&lowmem_deathpending_lock, flags);
- if (!lowmem_deathpending) {
- lowmem_print(1,
- "send sigkill to %d (%s), adj %d, size %d\n",
- selected->pid, selected->comm,
- selected_oom_adj, selected_tasksize);
- lowmem_deathpending = selected;
- task_free_register(&task_nb);
- force_sig(SIGKILL, selected);
- rem -= selected_tasksize;
- }
- spin_unlock_irqrestore(&lowmem_deathpending_lock, flags);
+ lowmem_print(1, "send sigkill to %d (%s), adj %d, size %d\n",
+ selected->pid, selected->comm,
+ selected_oom_adj, selected_tasksize);
+ lowmem_deathpending = selected;
+ lowmem_deathpending_timeout = jiffies + HZ;
+ force_sig(SIGKILL, selected);
+ rem -= selected_tasksize;
}
lowmem_print(4, "lowmem_shrink %d, %x, return %d\n",
nr_to_scan, gfp_mask, rem);
@@ -202,15 +249,93 @@ static struct shrinker lowmem_shrinker = {
.seeks = DEFAULT_SEEKS * 16
};
+static void lowmem_notify_killzone_approach(void)
+{
+ lowmem_print(3, "notification trigger activated\n");
+ sysfs_notify(lowmem_kobj, NULL, "notify_trigger_active");
+}
+
+static ssize_t lowmem_notify_trigger_active_show(struct kobject *k,
+ struct kobj_attribute *attr, char *buf)
+{
+ int other_free, other_file;
+ get_free_ram(&other_free, &other_file);
+ if (other_free < lowmem_minfree_notif_trigger &&
+ other_file < lowmem_minfree_notif_trigger)
+ return snprintf(buf, 3, "1\n");
+ else
+ return snprintf(buf, 3, "0\n");
+}
+
+static struct kobj_attribute lowmem_notify_trigger_active_attr =
+ __ATTR(notify_trigger_active, S_IRUGO,
+ lowmem_notify_trigger_active_show, NULL);
+
+static struct attribute *lowmem_default_attrs[] = {
+ &lowmem_notify_trigger_active_attr.attr,
+ NULL,
+};
+
+static ssize_t lowmem_show(struct kobject *k, struct attribute *attr, char *buf)
+{
+ struct kobj_attribute *kobj_attr;
+ kobj_attr = container_of(attr, struct kobj_attribute, attr);
+ return kobj_attr->show(k, kobj_attr, buf);
+}
+
+static const struct sysfs_ops lowmem_ops = {
+ .show = lowmem_show,
+};
+
+static void lowmem_kobj_release(struct kobject *kobj)
+{
+ /* Nothing to be done here */
+}
+
+static struct kobj_type lowmem_kobj_type = {
+ .release = lowmem_kobj_release,
+ .sysfs_ops = &lowmem_ops,
+ .default_attrs = lowmem_default_attrs,
+};
+
static int __init lowmem_init(void)
{
+ int rc;
+ task_free_register(&task_nb);
register_shrinker(&lowmem_shrinker);
+#ifdef CONFIG_MEMORY_HOTPLUG
+ hotplug_memory_notifier(lmk_hotplug_callback, 0);
+#endif
+
+ lowmem_kobj = kzalloc(sizeof(*lowmem_kobj), GFP_KERNEL);
+ if (!lowmem_kobj) {
+ rc = -ENOMEM;
+ goto err;
+ }
+
+ rc = kobject_init_and_add(lowmem_kobj, &lowmem_kobj_type,
+ mm_kobj, "lowmemkiller");
+ if (rc)
+ goto err_kobj;
+
return 0;
+
+err_kobj:
+ kfree(lowmem_kobj);
+
+err:
+ unregister_shrinker(&lowmem_shrinker);
+ task_free_unregister(&task_nb);
+
+ return rc;
}
static void __exit lowmem_exit(void)
{
+ kobject_put(lowmem_kobj);
+ kfree(lowmem_kobj);
unregister_shrinker(&lowmem_shrinker);
+ task_free_unregister(&task_nb);
}
module_param_named(cost, lowmem_shrinker.seeks, int, S_IRUGO | S_IWUSR);
@@ -219,6 +344,8 @@ module_param_array_named(adj, lowmem_adj, int, &lowmem_adj_size,
module_param_array_named(minfree, lowmem_minfree, uint, &lowmem_minfree_size,
S_IRUGO | S_IWUSR);
module_param_named(debug_level, lowmem_debug_level, uint, S_IRUGO | S_IWUSR);
+module_param_named(notify_trigger, lowmem_minfree_notif_trigger, uint,
+ S_IRUGO | S_IWUSR);
module_init(lowmem_init);
module_exit(lowmem_exit);