From: Chen Hui judy.chenhui@huawei.com
hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5KUFB CVE: NA
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Add user interface of task group tag, bridges the information gap between user-mode and kernel-mode.
Signed-off-by: Chen Hui judy.chenhui@huawei.com Signed-off-by: Ren Zhijie renzhijie2@huawei.com --- kernel/sched/core.c | 81 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index c53c032a378a..2256ac22d26d 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -8637,6 +8637,80 @@ static inline s64 cpu_qos_read(struct cgroup_subsys_state *css, } #endif
+#ifdef CONFIG_BPF_SCHED +static void sched_settag(struct task_struct *tsk, s64 tag) +{ + int queued, running, queue_flags = + DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK; + struct rq_flags rf; + struct rq *rq; + + if (tsk->tag == tag) + return; + + rq = task_rq_lock(tsk, &rf); + + running = task_current(rq, tsk); + queued = task_on_rq_queued(tsk); + + update_rq_clock(rq); + if (queued) + dequeue_task(rq, tsk, queue_flags); + if (running) + put_prev_task(rq, tsk); + + tsk->tag = tag; + + if (queued) + enqueue_task(rq, tsk, queue_flags); + if (running) + set_next_task(rq, tsk); + + task_rq_unlock(rq, tsk, &rf); +} + +static int tg_change_tag(struct task_group *tg, void *data) +{ + struct css_task_iter it; + struct task_struct *tsk; + s64 tag = *(s64 *)data; + struct cgroup_subsys_state *css = &tg->css; + + tg->tag = tag; + + css_task_iter_start(css, 0, &it); + while ((tsk = css_task_iter_next(&it))) + sched_settag(tsk, tag); + css_task_iter_end(&it); + + return 0; +} + +static int cpu_tag_write(struct cgroup_subsys_state *css, + struct cftype *cftype, s64 tag) +{ + struct task_group *tg = css_tg(css); + + if (tg == &root_task_group) + return -EINVAL; + + if (tg->tag == tag) + return 0; + + rcu_read_lock(); + walk_tg_tree_from(tg, tg_change_tag, tg_nop, (void *)(&tag)); + rcu_read_unlock(); + + return 0; +} + +static inline s64 cpu_tag_read(struct cgroup_subsys_state *css, + struct cftype *cft) +{ + return css_tg(css)->tag; +} +#endif + static struct cftype cpu_legacy_files[] = { #ifdef CONFIG_FAIR_GROUP_SCHED { @@ -8698,6 +8772,13 @@ static struct cftype cpu_legacy_files[] = { .read_s64 = cpu_qos_read, .write_s64 = cpu_qos_write, }, +#endif +#ifdef CONFIG_BPF_SCHED + { + .name = "tag", + .read_s64 = cpu_tag_read, + .write_s64 = cpu_tag_write, + }, #endif { } /* Terminate */ };