sched/walt: Accounting for number of irqs pending on each core

[firefly-linux-kernel-4.4.55.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 47851dbc893d1ee1e952bf6ef37792c59f1af77b..f53e61f95b5500cfad27527956f3ea971dd42411 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -4848,6 +4848,7 @@ static void init_and_link_css(struct cgroup_subsys_state *css,
        memset(css, 0, sizeof(*css));
        css->cgroup = cgrp;
        css->ss = ss;
+       css->id = -1;
        INIT_LIST_HEAD(&css->sibling);
        INIT_LIST_HEAD(&css->children);
        css->serial_nr = css_serial_nr_next++;
@@ -5379,6 +5380,12 @@ int __init cgroup_init(void)
        BUG_ON(cgroup_init_cftypes(NULL, cgroup_dfl_base_files));
        BUG_ON(cgroup_init_cftypes(NULL, cgroup_legacy_base_files));
 
+       /*
+        * The latency of the synchronize_sched() is too high for cgroups,
+        * avoid it at the cost of forcing all readers into the slow path.
+        */
+       rcu_sync_enter_start(&cgroup_threadgroup_rwsem.rss);
+
        mutex_lock(&cgroup_mutex);
 
        /* Add init_css_set to the hash table */