From: Guopeng Zhang <[email protected]> compute_partition_effective_cpumask() checks whether each valid child partition remains covered by the parent exclusive CPU mask and whether it would consume all remaining CPUs of a populated parent.
Factor these two checks into child_partition_error() so the same rules can be reused when evaluating a proposed parent configuration. This is a preparatory refactoring with no intended functional change. Signed-off-by: Guopeng Zhang <[email protected]> --- kernel/cgroup/cpuset.c | 38 +++++++++++++++++++++++++++++--------- 1 file changed, 29 insertions(+), 9 deletions(-) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 8f24171b6055..6994dc75d940 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -2085,6 +2085,26 @@ static int update_parent_effective_cpumask(struct cpuset *cs, int cmd, return 0; } +/* + * Return the error that will invalidate a child partition under a proposed + * parent partition configuration. + */ +static enum prs_errcode +child_partition_error(struct cpuset *child, + const struct cpumask *partition_cpus, + const struct cpumask *remaining_cpus, + bool parent_populated) +{ + if (!cpumask_subset(child->effective_xcpus, partition_cpus)) + return PERR_INVCPUS; + + if (parent_populated && + cpumask_subset(remaining_cpus, child->effective_xcpus)) + return PERR_NOCPUS; + + return PERR_NONE; +} + /** * compute_partition_effective_cpumask - compute effective_cpus for partition * @cs: partition root cpuset @@ -2121,6 +2141,8 @@ static void compute_partition_effective_cpumask(struct cpuset *cs, rcu_read_lock(); cpuset_for_each_child(child, css, cs) { + enum prs_errcode child_err; + if (!is_partition_valid(child)) continue; @@ -2129,15 +2151,13 @@ static void compute_partition_effective_cpumask(struct cpuset *cs, * partition root. */ WARN_ON_ONCE(is_remote_partition(child)); - WRITE_ONCE(child->prs_err, 0); - if (!cpumask_subset(child->effective_xcpus, - cs->effective_xcpus)) - WRITE_ONCE(child->prs_err, PERR_INVCPUS); - else if (populated && - cpumask_subset(new_ecpus, child->effective_xcpus)) - WRITE_ONCE(child->prs_err, PERR_NOCPUS); - - if (child->prs_err) { + WRITE_ONCE(child->prs_err, PERR_NONE); + child_err = child_partition_error(child, cs->effective_xcpus, + new_ecpus, populated); + if (child_err) + WRITE_ONCE(child->prs_err, child_err); + + if (child_err) { int old_prs = child->partition_root_state; /* -- 2.43.0
