From c8f699bb56aeae951e02fe2a46c9ada022535770 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 7 Jan 2013 08:51:07 -0800 Subject: cpuset: introduce ->css_on/offline() Add cpuset_css_on/offline() and rearrange css init/exit such that, * Allocation and clearing to the default values happen in css_alloc(). Allocation now uses kzalloc(). * Config inheritance and registration happen in css_online(). * css_offline() undoes what css_online() did. * css_free() frees. This doesn't introduce any visible behavior changes. This will help cleaning up locking. Signed-off-by: Tejun Heo Acked-by: Li Zefan --- kernel/cpuset.c | 66 ++++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 44 insertions(+), 22 deletions(-) (limited to 'kernel/cpuset.c') diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 5372b6f5e5b..1d7a611ff77 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -1790,15 +1790,12 @@ static struct cftype files[] = { static struct cgroup_subsys_state *cpuset_css_alloc(struct cgroup *cont) { - struct cgroup *parent_cg = cont->parent; - struct cgroup *tmp_cg; - struct cpuset *parent, *cs; + struct cpuset *cs; - if (!parent_cg) + if (!cont->parent) return &top_cpuset.css; - parent = cgroup_cs(parent_cg); - cs = kmalloc(sizeof(*cs), GFP_KERNEL); + cs = kzalloc(sizeof(*cs), GFP_KERNEL); if (!cs) return ERR_PTR(-ENOMEM); if (!alloc_cpumask_var(&cs->cpus_allowed, GFP_KERNEL)) { @@ -1806,22 +1803,34 @@ static struct cgroup_subsys_state *cpuset_css_alloc(struct cgroup *cont) return ERR_PTR(-ENOMEM); } - cs->flags = 0; - if (is_spread_page(parent)) - set_bit(CS_SPREAD_PAGE, &cs->flags); - if (is_spread_slab(parent)) - set_bit(CS_SPREAD_SLAB, &cs->flags); set_bit(CS_SCHED_LOAD_BALANCE, &cs->flags); cpumask_clear(cs->cpus_allowed); nodes_clear(cs->mems_allowed); fmeter_init(&cs->fmeter); cs->relax_domain_level = -1; + cs->parent = cgroup_cs(cont->parent); + + return &cs->css; +} + +static int cpuset_css_online(struct cgroup *cgrp) +{ + struct cpuset *cs = cgroup_cs(cgrp); + struct cpuset *parent = cs->parent; + struct cgroup *tmp_cg; + + if (!parent) + return 0; + + if (is_spread_page(parent)) + set_bit(CS_SPREAD_PAGE, &cs->flags); + if (is_spread_slab(parent)) + set_bit(CS_SPREAD_SLAB, &cs->flags); - cs->parent = parent; number_of_cpusets++; - if (!test_bit(CGRP_CPUSET_CLONE_CHILDREN, &cont->flags)) - goto skip_clone; + if (!test_bit(CGRP_CPUSET_CLONE_CHILDREN, &cgrp->flags)) + return 0; /* * Clone @parent's configuration if CGRP_CPUSET_CLONE_CHILDREN is @@ -1836,19 +1845,34 @@ static struct cgroup_subsys_state *cpuset_css_alloc(struct cgroup *cont) * changed to grant parent->cpus_allowed-sibling_cpus_exclusive * (and likewise for mems) to the new cgroup. */ - list_for_each_entry(tmp_cg, &parent_cg->children, sibling) { + list_for_each_entry(tmp_cg, &cgrp->parent->children, sibling) { struct cpuset *tmp_cs = cgroup_cs(tmp_cg); if (is_mem_exclusive(tmp_cs) || is_cpu_exclusive(tmp_cs)) - goto skip_clone; + return 0; } mutex_lock(&callback_mutex); cs->mems_allowed = parent->mems_allowed; cpumask_copy(cs->cpus_allowed, parent->cpus_allowed); mutex_unlock(&callback_mutex); -skip_clone: - return &cs->css; + + return 0; +} + +static void cpuset_css_offline(struct cgroup *cgrp) +{ + struct cpuset *cs = cgroup_cs(cgrp); + + /* css_offline is called w/o cgroup_mutex, grab it */ + cgroup_lock(); + + if (is_sched_load_balance(cs)) + update_flag(CS_SCHED_LOAD_BALANCE, cs, 0); + + number_of_cpusets--; + + cgroup_unlock(); } /* @@ -1861,10 +1885,6 @@ static void cpuset_css_free(struct cgroup *cont) { struct cpuset *cs = cgroup_cs(cont); - if (is_sched_load_balance(cs)) - update_flag(CS_SCHED_LOAD_BALANCE, cs, 0); - - number_of_cpusets--; free_cpumask_var(cs->cpus_allowed); kfree(cs); } @@ -1872,6 +1892,8 @@ static void cpuset_css_free(struct cgroup *cont) struct cgroup_subsys cpuset_subsys = { .name = "cpuset", .css_alloc = cpuset_css_alloc, + .css_online = cpuset_css_online, + .css_offline = cpuset_css_offline, .css_free = cpuset_css_free, .can_attach = cpuset_can_attach, .attach = cpuset_attach, -- cgit v1.2.3