From: Unsung Lee <unsung.lee@samsung.com>
Date: Tue, 15 Mar 2022 07:32:51 +0000 (+0900)
Subject: Enhance exception handling of memlimit
X-Git-Tag: submit/tizen/20220425.104329~15
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=refs%2Fchanges%2F56%2F272356%2F5;p=platform%2Fcore%2Fsystem%2Fresourced.git

Enhance exception handling of memlimit

consider panic on oom case

Change-Id: Ie609129858b035b3e2a14a69d1ff834c1b1c3563
Signed-off-by: Unsung Lee <unsung.lee@samsung.com>
---

diff --git a/src/resource-limiter/memory/lowmem-handler.h b/src/resource-limiter/memory/lowmem-handler.h
index 846a957..02e5b89 100644
--- a/src/resource-limiter/memory/lowmem-handler.h
+++ b/src/resource-limiter/memory/lowmem-handler.h
@@ -65,7 +65,6 @@ struct memory_limit_event {
 	unsigned int threshold;
 	char *path;
 	enum proc_action action;
-	GSource *sigterm_timer;
 	int pid;
 };
 
diff --git a/src/resource-limiter/memory/lowmem-limit.c b/src/resource-limiter/memory/lowmem-limit.c
index 69e1720..3be0115 100644
--- a/src/resource-limiter/memory/lowmem-limit.c
+++ b/src/resource-limiter/memory/lowmem-limit.c
@@ -51,6 +51,7 @@
 #include "fd-handler.h"
 #include "dbus-handler.h"
 #include "safe-kill.h"
+#include "file-helper.h"
 
 #define MEM_CONF_FILE                   RD_CONFIG_FILE(limiter)
 #define MEMLIMIT_CONFIG_SECTION	"MemLimit"
@@ -223,7 +224,6 @@ static gboolean liveness_check_cb(gpointer data)
 
 mle_timer_init:
 	mle->pid = -1;
-	mle->sigterm_timer = NULL;
 timer_out:
 	return G_SOURCE_REMOVE;
 }
@@ -232,7 +232,7 @@ static bool memory_action_cb(int fd, void *data)
 {
 	int result;
 	pid_t main_pid;
-	uint32_t usage, anon_usage, max_mem;
+	uint32_t usage, max_mem;
 	uint64_t dummy_efd;
 	char *cg_dir = (char *)data;
 	struct memory_limit_event *mle;
@@ -277,13 +277,13 @@ static bool memory_action_cb(int fd, void *data)
 		goto remove_mle;
 	}
 
-	anon_usage = mem_stat->value[CGROUP_MEMORY_STAT_RSS] +
+/*	anon_usage = mem_stat->value[CGROUP_MEMORY_STAT_RSS] +
 		mem_stat->value[CGROUP_MEMORY_STAT_SWAP];
 	if (anon_usage < mle->threshold) {
 		_D("[DEBUG] (%s) cgroup escaped low memory status. usage(%d), anon usage (%d), threshold(%d)",
 				cg_dir, usage, anon_usage, mle->threshold);
 		return true;
-	}
+	}*/
 
 	switch (mle->action) {
 		case PROC_ACTION_BROADCAST:
@@ -309,10 +309,11 @@ static bool memory_action_cb(int fd, void *data)
 			}
 			safe_kill(main_pid, SIGTERM);
 
-			if (mle->sigterm_timer == NULL) {
+			if (mle->pid == -1) {
 				mle->pid = main_pid;
 				g_timeout_add_seconds(2, liveness_check_cb, mle);
 			}
+
 			break;
 		default:
 			_E("[DEBUG] Unkown action of memory threshold");
@@ -325,12 +326,33 @@ remove_mle:
 	return false;
 }
 
+static void set_limit_in_bytes(const char *dir, unsigned int limit)
+{
+	int error;
+	unsigned int prev;
+
+	error = cgroup_read_node_uint32(dir, MEMCG_LIMIT_BYTE, &prev);
+	if (error) {
+		_E("[DEBUG] Failed to get %s from %s", MEMCG_LIMIT_BYTE, dir);
+		return;
+	}
+
+	if (prev > (limit * 1.2)) {
+		cgroup_write_node_uint32(dir, MEMCG_LIMIT_BYTE, (limit * 1.2));
+		cgroup_write_node_uint32(dir, MEMCG_SWAP_LIMIT_BYTE, (limit * 1.2));
+	}
+	else {
+		cgroup_write_node_uint32(dir, MEMCG_SWAP_LIMIT_BYTE, (limit * 1.2));
+		cgroup_write_node_uint32(dir, MEMCG_LIMIT_BYTE, (limit * 1.2));
+	}
+}
+
 int lowmem_reassign_limit(const char *dir,
 		unsigned int limit, enum proc_action action)
 {
 	int fd;
 	int error;
-	unsigned int prev;
+	unsigned int poo;
 	fd_handler_h fdh = NULL;
 	gpointer hash_entry;
 	struct memory_limit_event *mle = NULL;
@@ -358,19 +380,21 @@ int lowmem_reassign_limit(const char *dir,
 		}
 	}
 
-	error = cgroup_read_node_uint32(dir, MEMCG_LIMIT_BYTE, &prev);
+	error = fread_uint("/proc/sys/vm/panic_on_oom", &poo);
 	if (error) {
-		_E("[DEBUG] Failed to get %s from %s", MEMCG_LIMIT_BYTE, dir);
+		_E("[DEBUG] Failed to get %s from %s", "/proc/sys/vm/panic_on_oom", dir);
 		return RESOURCED_ERROR_FAIL;
 	}
 
-	if (prev > (limit * 1.2)) {
-		cgroup_write_node_uint32(dir, MEMCG_LIMIT_BYTE, (limit * 1.2));
-		cgroup_write_node_uint32(dir, MEMCG_SWAP_LIMIT_BYTE, (limit * 1.2));
+	/* If panic_on_oom is true (> 1), oom should be disabled  */
+	if (poo != 0) {
+		_I("%s's value is %d. That is, kernel panic will be inevitable, when oom happens", "proc/sys/vm/panic_on_oom", poo);
+		error = cgroup_write_node_uint32(dir, MEMCG_OOM_CONTROL, 1);
+		if (!error)
+			set_limit_in_bytes(dir, limit);
 	}
 	else {
-		cgroup_write_node_uint32(dir, MEMCG_SWAP_LIMIT_BYTE, (limit * 1.2));
-		cgroup_write_node_uint32(dir, MEMCG_LIMIT_BYTE, (limit * 1.2));
+		set_limit_in_bytes(dir, limit);
 	}
 
 	snprintf(buf, sizeof(buf), "%d", limit);
@@ -398,7 +422,6 @@ int lowmem_reassign_limit(const char *dir,
 		mle->action = action;
 		mle->threshold = limit;
 		mle->pid = -1;
-		mle->sigterm_timer = NULL;
 		add_fd_read_handler(fd, memory_action_cb, mle->path, NULL, &fdh);
 		mle->fdh = fdh;
 		g_hash_table_insert(memory_limit_hash, (gpointer)mle->path,
@@ -496,7 +519,11 @@ void lowmem_limit_set_system_service(pid_t pid, unsigned int limit,
 		return;
 	}
 
-	lowmem_reassign_limit(path, limit, action);
+	result = lowmem_reassign_limit(path, limit, action);
+	if (result < 0) {
+		_W("Failed to reassign limit for %s", path);
+		return;
+	}
 
 	result = cgroup_write_node_uint32(path, MEMCG_MOVE_CHARGE, 3U);
 	if (result < 0)