From 2260e7fc1f18ad815324605c1ce7d5c6fd9b19a2 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 19 Nov 2012 08:13:38 -0800 Subject: [PATCH] cgroup: s/CGRP_CLONE_CHILDREN/CGRP_CPUSET_CLONE_CHILDREN/ clone_children is only meaningful for cpuset and will stay that way. Rename the flag to reflect that and update documentation. Also, drop clone_children() wrapper in cgroup.c. The thin wrapper is used only a few times and one of them will go away soon. Signed-off-by: Tejun Heo Acked-by: Serge E. Hallyn Acked-by: Li Zefan Cc: Glauber Costa --- Documentation/cgroups/cgroups.txt | 8 +++----- include/linux/cgroup.h | 6 ++++-- kernel/cgroup.c | 28 ++++++++++++---------------- 3 files changed, 19 insertions(+), 23 deletions(-) diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt index b06eea217403..24cdf76bd20c 100644 --- a/Documentation/cgroups/cgroups.txt +++ b/Documentation/cgroups/cgroups.txt @@ -299,11 +299,9 @@ a cgroup hierarchy's release_agent path is empty. 1.5 What does clone_children do ? --------------------------------- -If the clone_children flag is enabled (1) in a cgroup, then all -cgroups created beneath will call the post_clone callbacks for each -subsystem of the newly created cgroup. Usually when this callback is -implemented for a subsystem, it copies the values of the parent -subsystem, this is the case for the cpuset. +This flag only affects the cpuset controller. If the clone_children +flag is enabled (1) in a cgroup, a new cpuset cgroup will copy its +configuration from the parent during initialization. 1.6 How do I use cgroups ? -------------------------- diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 7a2189ca8327..d2f82979f6c1 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -143,9 +143,11 @@ enum { /* Control Group requires release notifications to userspace */ CGRP_NOTIFY_ON_RELEASE, /* - * Clone cgroup values when creating a new child cgroup + * Clone the parent's configuration when creating a new child + * cpuset cgroup. For historical reasons, this option can be + * specified at mount time and thus is implemented here. */ - CGRP_CLONE_CHILDREN, + CGRP_CPUSET_CLONE_CHILDREN, }; struct cgroup { diff --git a/kernel/cgroup.c b/kernel/cgroup.c index d35463bab487..2895880e6800 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -296,11 +296,6 @@ static int notify_on_release(const struct cgroup *cgrp) return test_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags); } -static int clone_children(const struct cgroup *cgrp) -{ - return test_bit(CGRP_CLONE_CHILDREN, &cgrp->flags); -} - /* * for_each_subsys() allows you to iterate on each subsystem attached to * an active hierarchy @@ -1101,7 +1096,7 @@ static int cgroup_show_options(struct seq_file *seq, struct dentry *dentry) seq_puts(seq, ",xattr"); if (strlen(root->release_agent_path)) seq_printf(seq, ",release_agent=%s", root->release_agent_path); - if (clone_children(&root->top_cgroup)) + if (test_bit(CGRP_CPUSET_CLONE_CHILDREN, &root->top_cgroup.flags)) seq_puts(seq, ",clone_children"); if (strlen(root->name)) seq_printf(seq, ",name=%s", root->name); @@ -1113,7 +1108,7 @@ struct cgroup_sb_opts { unsigned long subsys_mask; unsigned long flags; char *release_agent; - bool clone_children; + bool cpuset_clone_children; char *name; /* User explicitly requested empty subsystem */ bool none; @@ -1164,7 +1159,7 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts) continue; } if (!strcmp(token, "clone_children")) { - opts->clone_children = true; + opts->cpuset_clone_children = true; continue; } if (!strcmp(token, "xattr")) { @@ -1474,8 +1469,8 @@ static struct cgroupfs_root *cgroup_root_from_opts(struct cgroup_sb_opts *opts) strcpy(root->release_agent_path, opts->release_agent); if (opts->name) strcpy(root->name, opts->name); - if (opts->clone_children) - set_bit(CGRP_CLONE_CHILDREN, &root->top_cgroup.flags); + if (opts->cpuset_clone_children) + set_bit(CGRP_CPUSET_CLONE_CHILDREN, &root->top_cgroup.flags); return root; } @@ -3905,7 +3900,7 @@ static int cgroup_write_event_control(struct cgroup *cgrp, struct cftype *cft, static u64 cgroup_clone_children_read(struct cgroup *cgrp, struct cftype *cft) { - return clone_children(cgrp); + return test_bit(CGRP_CPUSET_CLONE_CHILDREN, &cgrp->flags); } static int cgroup_clone_children_write(struct cgroup *cgrp, @@ -3913,9 +3908,9 @@ static int cgroup_clone_children_write(struct cgroup *cgrp, u64 val) { if (val) - set_bit(CGRP_CLONE_CHILDREN, &cgrp->flags); + set_bit(CGRP_CPUSET_CLONE_CHILDREN, &cgrp->flags); else - clear_bit(CGRP_CLONE_CHILDREN, &cgrp->flags); + clear_bit(CGRP_CPUSET_CLONE_CHILDREN, &cgrp->flags); return 0; } @@ -4130,8 +4125,8 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, if (notify_on_release(parent)) set_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags); - if (clone_children(parent)) - set_bit(CGRP_CLONE_CHILDREN, &cgrp->flags); + if (test_bit(CGRP_CPUSET_CLONE_CHILDREN, &parent->flags)) + set_bit(CGRP_CPUSET_CLONE_CHILDREN, &cgrp->flags); for_each_subsys(root, ss) { struct cgroup_subsys_state *css; @@ -4148,7 +4143,8 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, goto err_free_all; } /* At error, ->css_free() callback has to free assigned ID. */ - if (clone_children(parent) && ss->post_clone) + if (test_bit(CGRP_CPUSET_CLONE_CHILDREN, &parent->flags) && + ss->post_clone) ss->post_clone(cgrp); if (ss->broken_hierarchy && !ss->warned_broken_hierarchy &&