diff options
Diffstat (limited to 'kernel/cgroup')
| -rw-r--r-- | kernel/cgroup/cpuset.c | 69 |
1 files changed, 60 insertions, 9 deletions
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index b0d921d03f62..6baa977a71ba 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -1256,6 +1256,7 @@ enum subparts_cmd { partcmd_enable, /* Enable partition root */ partcmd_disable, /* Disable partition root */ partcmd_update, /* Update parent's subparts_cpus */ + partcmd_invalidate, /* Make partition invalid */ }; static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, @@ -1286,13 +1287,17 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, * or vice versa. An error code will only be returned if transitioning from * invalid to valid violates the exclusivity rule. * + * For partcmd_invalidate, the current partition will be made invalid. + * * The partcmd_enable and partcmd_disable commands are used by * update_prstate(). An error code may be returned and the caller will check * for error. * * The partcmd_update command is used by update_cpumasks_hier() with newmask - * NULL and update_cpumask() with newmask set. The callers won't check for - * error and so partition_root_state and prs_error will be updated directly. + * NULL and update_cpumask() with newmask set. The partcmd_invalidate is used + * by update_cpumask() with NULL newmask. In both cases, the callers won't + * check for error and so partition_root_state and prs_error will be updated + * directly. */ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, struct cpumask *newmask, @@ -1320,7 +1325,8 @@ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, return PERR_CPUSEMPTY; /* - * new_prs will only be changed for the partcmd_update command. + * new_prs will only be changed for the partcmd_update and + * partcmd_invalidate commands. */ adding = deleting = false; old_prs = new_prs = cs->partition_root_state; @@ -1350,6 +1356,20 @@ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, deleting = !is_prs_invalid(old_prs) && cpumask_and(tmp->delmask, cs->cpus_allowed, parent->subparts_cpus); + } else if (cmd == partcmd_invalidate) { + if (is_prs_invalid(old_prs)) + return 0; + + /* + * Make the current partition invalid. It is assumed that + * invalidation is caused by violating cpu exclusivity rule. + */ + deleting = cpumask_and(tmp->delmask, cs->cpus_allowed, + parent->subparts_cpus); + if (old_prs > 0) { + new_prs = -old_prs; + part_error = PERR_NOTEXCL; + } } else if (newmask) { /* * partcmd_update with newmask: @@ -1403,6 +1423,7 @@ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, parent->cpus_allowed); adding = cpumask_andnot(tmp->addmask, tmp->addmask, parent->subparts_cpus); + if ((is_partition_valid(cs) && !parent->nr_subparts_cpus) || (adding && cpumask_subset(parent->effective_cpus, tmp->addmask) && @@ -1709,6 +1730,7 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, { int retval; struct tmpmasks tmp; + bool invalidate = false; /* top_cpuset.cpus_allowed tracks cpu_online_mask; it's read-only */ if (cs == &top_cpuset) @@ -1736,10 +1758,6 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, if (cpumask_equal(cs->cpus_allowed, trialcs->cpus_allowed)) return 0; - retval = validate_change(cs, trialcs); - if (retval < 0) - return retval; - #ifdef CONFIG_CPUMASK_OFFSTACK /* * Use the cpumasks in trialcs for tmpmasks when they are pointers @@ -1750,9 +1768,42 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, tmp.new_cpus = trialcs->cpus_allowed; #endif + retval = validate_change(cs, trialcs); + + if ((retval == -EINVAL) && cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) { + struct cpuset *cp, *parent; + struct cgroup_subsys_state *css; + + /* + * The -EINVAL error code indicates that partition sibling + * CPU exclusivity rule has been violated. We still allow + * the cpumask change to proceed while invalidating the + * partition. However, any conflicting sibling partitions + * have to be marked as invalid too. + */ + invalidate = true; + rcu_read_lock(); + parent = parent_cs(cs); + cpuset_for_each_child(cp, css, parent) + if (is_partition_valid(cp) && + cpumask_intersects(trialcs->cpus_allowed, cp->cpus_allowed)) { + rcu_read_unlock(); + update_parent_subparts_cpumask(cp, partcmd_invalidate, NULL, &tmp); + rcu_read_lock(); + } + rcu_read_unlock(); + retval = 0; + } + if (retval < 0) + return retval; + if (cs->partition_root_state) { - update_parent_subparts_cpumask(cs, partcmd_update, - trialcs->cpus_allowed, &tmp); + if (invalidate) + update_parent_subparts_cpumask(cs, partcmd_invalidate, + NULL, &tmp); + else + update_parent_subparts_cpumask(cs, partcmd_update, + trialcs->cpus_allowed, &tmp); } compute_effective_cpumask(trialcs->effective_cpus, trialcs, |