openwrt/target/linux/brcm2708/patches-4.14/950-0136-cgroup-Disable-cgroup-memory-by-default.patch
David Bauer e902d11de9 kernel: bump 4.14 to 4.14.241
Refreshed all patches

Compile-tested: ath79-generic brcm2708-bcm2708
Run-tested: ath79-generic brcm2708-bcm2708

Signed-off-by: David Bauer <mail@david-bauer.net>
2021-07-28 17:23:36 +02:00

86 lines
2.3 KiB
Diff

From 66b3e537b50cd2b46b71edb6ffeef633d1224d10 Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Mon, 27 Nov 2017 17:14:54 +0000
Subject: [PATCH] cgroup: Disable cgroup "memory" by default
Some Raspberry Pis have limited RAM and most users won't use the
cgroup memory support so it is disabled by default. Enable with:
cgroup_enable=memory
See: https://github.com/raspberrypi/linux/issues/1950
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
kernel/cgroup/cgroup.c | 38 ++++++++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -5219,6 +5219,9 @@ int __init cgroup_init_early(void)
return 0;
}
+static u16 cgroup_enable_mask __initdata;
+static int __init cgroup_disable(char *str);
+
/**
* cgroup_init - cgroup initialization
*
@@ -5256,6 +5259,12 @@ int __init cgroup_init(void)
mutex_unlock(&cgroup_mutex);
+ /*
+ * Apply an implicit disable, knowing that an explicit enable will
+ * prevent if from doing anything.
+ */
+ cgroup_disable("memory");
+
for_each_subsys(ss, ssid) {
if (ss->early_init) {
struct cgroup_subsys_state *css =
@@ -5637,6 +5646,10 @@ static int __init cgroup_disable(char *s
strcmp(token, ss->legacy_name))
continue;
+ /* An explicit cgroup_enable overrides a disable */
+ if (cgroup_enable_mask & (1 << i))
+ continue;
+
static_branch_disable(cgroup_subsys_enabled_key[i]);
pr_info("Disabling %s control group subsystem\n",
ss->name);
@@ -5646,6 +5659,31 @@ static int __init cgroup_disable(char *s
}
__setup("cgroup_disable=", cgroup_disable);
+static int __init cgroup_enable(char *str)
+{
+ struct cgroup_subsys *ss;
+ char *token;
+ int i;
+
+ while ((token = strsep(&str, ",")) != NULL) {
+ if (!*token)
+ continue;
+
+ for_each_subsys(ss, i) {
+ if (strcmp(token, ss->name) &&
+ strcmp(token, ss->legacy_name))
+ continue;
+
+ cgroup_enable_mask |= 1 << i;
+ static_branch_enable(cgroup_subsys_enabled_key[i]);
+ pr_info("Enabling %s control group subsystem\n",
+ ss->name);
+ }
+ }
+ return 1;
+}
+__setup("cgroup_enable=", cgroup_enable);
+
/**
* css_tryget_online_from_dir - get corresponding css from a cgroup dentry
* @dentry: directory dentry of interest