With the latest changes in sched/isolation.c, rebuild_sched_domains*() requires the HK_TYPE_DOMAIN housekeeping cpumask to be properly updated first, if needed, before the sched domains can be rebuilt. So the two naturally fit together. Do that by creating a new update_hk_sched_domains() helper to house both actions.
The name of the isolated_cpus_updating flag to control the call to housekeeping_update() is now outdated. So change it to update_housekeeping to better reflect its purpose. Also move the call to update_hk_sched_domains() to the end of cpuset and hotplug operations before releasing the cpuset_mutex. Signed-off-by: Waiman Long <[email protected]> --- kernel/cgroup/cpuset.c | 51 ++++++++++++++++++++---------------------- 1 file changed, 24 insertions(+), 27 deletions(-) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 05adf6697030..3d0d18bf182f 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -130,10 +130,9 @@ static cpumask_var_t subpartitions_cpus; /* RWCS */ static cpumask_var_t isolated_cpus; /* CSCB */ /* - * Set if isolated_cpus is being updated in the current cpuset_mutex - * critical section. + * Set if housekeeping cpumasks are to be updated. */ -static bool isolated_cpus_updating; /* RWCS */ +static bool update_housekeeping; /* RWCS */ /* * A flag to force sched domain rebuild at the end of an operation. @@ -1188,7 +1187,7 @@ static void isolated_cpus_update(int old_prs, int new_prs, struct cpumask *xcpus return; cpumask_andnot(isolated_cpus, isolated_cpus, xcpus); } - isolated_cpus_updating = true; + update_housekeeping = true; } /* @@ -1306,22 +1305,22 @@ static bool prstate_housekeeping_conflict(int prstate, struct cpumask *new_cpus) } /* - * update_isolation_cpumasks - Update external isolation related CPU masks + * update_hk_sched_domains - Update HK cpumasks & rebuild sched domains * - * The following external CPU masks will be updated if necessary: - * - workqueue unbound cpumask + * Update housekeeping cpumasks and rebuild sched domains if necessary. + * This should be called at the end of cpuset or hotplug actions. */ -static void update_isolation_cpumasks(void) +static void update_hk_sched_domains(void) { - int ret; - - if (!isolated_cpus_updating) - return; - - ret = housekeeping_update(isolated_cpus); - WARN_ON_ONCE(ret < 0); - - isolated_cpus_updating = false; + if (update_housekeeping) { + /* Updating HK cpumasks implies rebuild sched domains */ + WARN_ON_ONCE(housekeeping_update(isolated_cpus)); + update_housekeeping = false; + force_sd_rebuild = true; + } + /* force_sd_rebuild will be cleared in rebuild_sched_domains_locked() */ + if (force_sd_rebuild) + rebuild_sched_domains_locked(); } /** @@ -1472,7 +1471,6 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs, cs->remote_partition = true; cpumask_copy(cs->effective_xcpus, tmp->new_cpus); spin_unlock_irq(&callback_lock); - update_isolation_cpumasks(); cpuset_force_rebuild(); cs->prs_err = 0; @@ -1517,7 +1515,6 @@ static void remote_partition_disable(struct cpuset *cs, struct tmpmasks *tmp) compute_excpus(cs, cs->effective_xcpus); reset_partition_data(cs); spin_unlock_irq(&callback_lock); - update_isolation_cpumasks(); cpuset_force_rebuild(); /* @@ -1588,7 +1585,6 @@ static void remote_cpus_update(struct cpuset *cs, struct cpumask *xcpus, if (xcpus) cpumask_copy(cs->exclusive_cpus, xcpus); spin_unlock_irq(&callback_lock); - update_isolation_cpumasks(); if (adding || deleting) cpuset_force_rebuild(); @@ -1932,7 +1928,6 @@ static int update_parent_effective_cpumask(struct cpuset *cs, int cmd, partition_xcpus_add(new_prs, parent, tmp->delmask); spin_unlock_irq(&callback_lock); - update_isolation_cpumasks(); if ((old_prs != new_prs) && (cmd == partcmd_update)) update_partition_exclusive_flag(cs, new_prs); @@ -2900,7 +2895,6 @@ static int update_prstate(struct cpuset *cs, int new_prs) else if (isolcpus_updated) isolated_cpus_update(old_prs, new_prs, cs->effective_xcpus); spin_unlock_irq(&callback_lock); - update_isolation_cpumasks(); /* Force update if switching back to member & update effective_xcpus */ update_cpumasks_hier(cs, &tmpmask, !new_prs); @@ -3190,9 +3184,8 @@ ssize_t cpuset_write_resmask(struct kernfs_open_file *of, } free_cpuset(trialcs); - if (force_sd_rebuild) - rebuild_sched_domains_locked(); out_unlock: + update_hk_sched_domains(); cpuset_full_unlock(); if (of_cft(of)->private == FILE_MEMLIST) schedule_flush_migrate_mm(); @@ -3300,6 +3293,7 @@ static ssize_t cpuset_partition_write(struct kernfs_open_file *of, char *buf, cpuset_full_lock(); if (is_cpuset_online(cs)) retval = update_prstate(cs, val); + update_hk_sched_domains(); cpuset_full_unlock(); return retval ?: nbytes; } @@ -3474,6 +3468,7 @@ static void cpuset_css_killed(struct cgroup_subsys_state *css) /* Reset valid partition back to member */ if (is_partition_valid(cs)) update_prstate(cs, PRS_MEMBER); + update_hk_sched_domains(); cpuset_full_unlock(); } @@ -3881,10 +3876,12 @@ static void cpuset_handle_hotplug(void) rcu_read_unlock(); } - /* rebuild sched domains if necessary */ - if (force_sd_rebuild) - rebuild_sched_domains_cpuslocked(); + if (update_housekeeping || force_sd_rebuild) { + mutex_lock(&cpuset_mutex); + update_hk_sched_domains(); + mutex_unlock(&cpuset_mutex); + } free_tmpmasks(ptmp); } -- 2.53.0

