kernel:mm: Support disable oom-killer and report oom events

ascend inclusion
category: feature
bugzilla: NA
CVE: NA

-------------------

Aascend support disable oom-killer and report oom events to bbox.
Signed-off-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NZhou Guanghui <zhouguanghui1@huawei.com>
Signed-off-by: NChen Jun <chenjin102@huawei.com>
Signed-off-by: NLijun Fang <fanglijun3@huawei.com>
Reviewed-by: NLi Zefan <lizefan@huawei.com>
Reviewed-by: NHanjun Guo <guohanjun@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

include/linux/oom.h

@@ -117,4 +117,18 @@ extern struct task_struct *find_lock_task_mm(struct task_struct *p);
 extern int sysctl_oom_dump_tasks;
 extern int sysctl_oom_kill_allocating_task;
 extern int sysctl_panic_on_oom;
+
+#ifdef CONFIG_ARCH_ASCEND
+
+extern int sysctl_enable_oom_killer;
+extern int register_hisi_oom_notifier(struct notifier_block *nb);
+extern int hisi_oom_notifier_call(unsigned long val, void *v);
+extern int unregister_hisi_oom_notifier(struct notifier_block *nb);
+
+#else
+
+#define sysctl_enable_oom_killer 1
+#define hisi_oom_notifier_call(val, p) ({NOTIFY_DONE; })
+#endif
+
 #endif /* _INCLUDE_LINUX_OOM_H */

kernel/sysctl.c

@@ -1264,6 +1264,17 @@ static struct ctl_table vm_table[] = {
 		.extra1		= &zero,
 		.extra2		= &two,
 	},
+#ifdef CONFIG_ARCH_ASCEND
+	{
+		.procname	= "enable_oom_killer",
+		.data		= &sysctl_enable_oom_killer,
+		.maxlen		= sizeof(sysctl_enable_oom_killer),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &one,
+	},
+#endif
 	{
 		.procname	= "oom_kill_allocating_task",
 		.data		= &sysctl_oom_kill_allocating_task,

mm/oom_kill.c

@@ -1047,6 +1047,40 @@ int unregister_oom_notifier(struct notifier_block *nb)
 }
 EXPORT_SYMBOL_GPL(unregister_oom_notifier);
 
+#ifdef CONFIG_ARCH_ASCEND
+
+int sysctl_enable_oom_killer;
+static BLOCKING_NOTIFIER_HEAD(hisi_oom_notify_list);
+
+int register_hisi_oom_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&hisi_oom_notify_list, nb);
+}
+EXPORT_SYMBOL_GPL(register_hisi_oom_notifier);
+
+static unsigned long last_jiffies;
+int hisi_oom_notifier_call(unsigned long val, void *v)
+{
+	/* Print time interval to 10 seconds */
+	if (time_after(jiffies, last_jiffies + 10 * HZ)) {
+		pr_warn("HISI_OOM_NOTIFIER: oom type %lu\n", val);
+		dump_stack();
+		show_mem(SHOW_MEM_FILTER_NODES, NULL);
+		dump_tasks(NULL, 0);
+		last_jiffies = jiffies;
+	}
+	return blocking_notifier_call_chain(&hisi_oom_notify_list, val, v);
+}
+EXPORT_SYMBOL_GPL(hisi_oom_notifier_call);
+
+int unregister_hisi_oom_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&hisi_oom_notify_list, nb);
+}
+EXPORT_SYMBOL_GPL(unregister_hisi_oom_notifier);
+
+#endif
+
 /**
  * out_of_memory - kill the "best" process when we run out of memory
  * @oc: pointer to struct oom_control
@@ -1064,6 +1098,11 @@ bool out_of_memory(struct oom_control *oc)
 	if (oom_killer_disabled)
 		return false;
 
+	if (!sysctl_enable_oom_killer) {
+		hisi_oom_notifier_call(0, NULL);
+		return false;
+	}
+
 	if (!is_memcg_oom(oc)) {
 		blocking_notifier_call_chain(&oom_notify_list, 0, &freed);
 		if (freed > 0)

mm/util.c

@@ -17,6 +17,7 @@
 
 #include <asm/sections.h>
 #include <linux/uaccess.h>
+#include <linux/oom.h>
 
 #include "internal.h"
 
@@ -726,6 +727,7 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
 	if (percpu_counter_read_positive(&vm_committed_as) < allowed)
 		return 0;
 error:
+	hisi_oom_notifier_call(1, NULL);
 	vm_unacct_memory(pages);
 
 	return -ENOMEM;