sched/topology: Wrappers for sched_domains_mutex

Create wrappers for sched_domains_mutex so that it can transparently be
used on both CONFIG_SMP and !CONFIG_SMP, as some function will need to
do.

Fixes: 53916d5fd3c0 ("sched/deadline: Check bandwidth overflow earlier for hotplug")
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Waiman Long <longman@redhat.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lore.kernel.org/r/Z9MP5Oq9RB8jBs3y@jlelli-thinkpadt14gen4.remote.csb

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 9632e3318e0d6bcc5abb647118d9aebb55edefe8..0785268c76f8e9d77a0d7d95f9a28e63d8331142 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -382,6 +382,11 @@ enum uclamp_id {
 #ifdef CONFIG_SMP
 extern struct root_domain def_root_domain;
 extern struct mutex sched_domains_mutex;
+extern void sched_domains_mutex_lock(void);
+extern void sched_domains_mutex_unlock(void);
+#else
+static inline void sched_domains_mutex_lock(void) { }
+static inline void sched_domains_mutex_unlock(void) { }
 #endif
 
 struct sched_param {

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 0f910c828973a9a2c026f37e5a504b2ff538bd8d..f87526edb2a46bc25eb95fc6ef7eb978b09a1bbf 100644 (file)
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -994,10 +994,10 @@ static void
 partition_and_rebuild_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
                                    struct sched_domain_attr *dattr_new)
 {
-       mutex_lock(&sched_domains_mutex);
+       sched_domains_mutex_lock();
        partition_sched_domains_locked(ndoms_new, doms_new, dattr_new);
        dl_rebuild_rd_accounting();
-       mutex_unlock(&sched_domains_mutex);
+       sched_domains_mutex_unlock();
 }
 
 /*

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c734724f7ff7d895351016c54726082469cc6380..84f68007e08f0bb2de176502db7ee3b9afd447de 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -8470,9 +8470,9 @@ void __init sched_init_smp(void)
         * CPU masks are stable and all blatant races in the below code cannot
         * happen.
         */
-       mutex_lock(&sched_domains_mutex);
+       sched_domains_mutex_lock();
        sched_init_domains(cpu_active_mask);
-       mutex_unlock(&sched_domains_mutex);
+       sched_domains_mutex_unlock();
 
        /* Move init over to a non-isolated CPU */
        if (set_cpus_allowed_ptr(current, housekeeping_cpumask(HK_TYPE_DOMAIN)) < 0)

diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 39be73969d28455649848a11bafd7a00476b7bc8..56ae54e0ce6a3616137cf3270e92ec529026e3c2 100644 (file)
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -294,7 +294,7 @@ static ssize_t sched_verbose_write(struct file *filp, const char __user *ubuf,
        bool orig;
 
        cpus_read_lock();
-       mutex_lock(&sched_domains_mutex);
+       sched_domains_mutex_lock();
 
        orig = sched_debug_verbose;
        result = debugfs_write_file_bool(filp, ubuf, cnt, ppos);
@@ -306,7 +306,7 @@ static ssize_t sched_verbose_write(struct file *filp, const char __user *ubuf,
                sd_dentry = NULL;
        }
 
-       mutex_unlock(&sched_domains_mutex);
+       sched_domains_mutex_unlock();
        cpus_read_unlock();
 
        return result;
@@ -517,9 +517,9 @@ static __init int sched_init_debug(void)
        debugfs_create_u32("migration_cost_ns", 0644, debugfs_sched, &sysctl_sched_migration_cost);
        debugfs_create_u32("nr_migrate", 0644, debugfs_sched, &sysctl_sched_nr_migrate);
 
-       mutex_lock(&sched_domains_mutex);
+       sched_domains_mutex_lock();
        update_sched_domain_debugfs();
-       mutex_unlock(&sched_domains_mutex);
+       sched_domains_mutex_unlock();
 #endif
 
 #ifdef CONFIG_NUMA_BALANCING

diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index c49aea8c10254dec985bba47b18f61be954d23f6..296ff2acfd321d18083e4470b4c6730cd764dc73 100644 (file)
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -6,6 +6,14 @@
 #include <linux/bsearch.h>
 
 DEFINE_MUTEX(sched_domains_mutex);
+void sched_domains_mutex_lock(void)
+{
+       mutex_lock(&sched_domains_mutex);
+}
+void sched_domains_mutex_unlock(void)
+{
+       mutex_unlock(&sched_domains_mutex);
+}
 
 /* Protected by sched_domains_mutex: */
 static cpumask_var_t sched_domains_tmpmask;
@@ -2791,7 +2799,7 @@ match3:
 void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
                             struct sched_domain_attr *dattr_new)
 {
-       mutex_lock(&sched_domains_mutex);
+       sched_domains_mutex_lock();
        partition_sched_domains_locked(ndoms_new, doms_new, dattr_new);
-       mutex_unlock(&sched_domains_mutex);
+       sched_domains_mutex_unlock();
 }