From 584bc4a6093ceb9aea07673185ee0084edc8690b Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Mon, 27 Nov 2017 17:14:54 +0000 Subject: [PATCH 136/454] 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 --- kernel/cgroup/cgroup.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -5154,6 +5154,8 @@ int __init cgroup_init_early(void) } static u16 cgroup_disable_mask __initdata; +static u16 cgroup_enable_mask __initdata; +static int __init cgroup_disable(char *str); /** * cgroup_init - cgroup initialization @@ -5192,6 +5194,12 @@ int __init cgroup_init(void) mutex_unlock(&cgroup_mutex); + /* Apply an implicit disable... */ + cgroup_disable("memory"); + + /* ...knowing that an explicit enable will override it. */ + cgroup_disable_mask &= ~cgroup_enable_mask; + for_each_subsys(ss, ssid) { if (ss->early_init) { struct cgroup_subsys_state *css = @@ -5572,6 +5580,28 @@ 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; + } + } + return 1; +} +__setup("cgroup_enable=", cgroup_enable); + /** * css_tryget_online_from_dir - get corresponding css from a cgroup dentry * @dentry: directory dentry of interest