From 40117635a8f22a05a4eed98c40fcaf67ad90f738 Mon Sep 17 00:00:00 2001 From: Yong Zhang Date: Wed, 22 Jun 2011 12:52:40 +0800 Subject: [PATCH] sched: skip autogroup when looking for all rt sched groups Since [commit ec514c48: sched: Fix rt_rq runtime leakage bug], 'cat /proc/sched_debug' will print data of root_task_group.rt_rq multi times, this is due to autogroup has no its own rt group, instead rt group of autogroup is linked to root_task_group. So skip it when we are looking for all rt sched groups, and it will also save some noop operation against root_task_group when __disable_runtime()/__enable_runtime(). Signed-off-by: Yong Zhang Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Mike Galbraith --- Since webmail may mangle the patch, attach it too. kernel/sched_autogroup.h | 1 + kernel/sched_rt.c | 29 ++++++++++++++++++++++++----- 2 files changed, 25 insertions(+), 5 deletions(-) diff --git a/kernel/sched_autogroup.h b/kernel/sched_autogroup.h index 0557705..c2f0e72 100644 --- a/kernel/sched_autogroup.h +++ b/kernel/sched_autogroup.h @@ -13,6 +13,7 @@ struct autogroup { int nice; }; +static inline bool task_group_is_autogroup(struct task_group *tg); static inline struct task_group * autogroup_task_group(struct task_struct *p, struct task_group *tg); diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index 10d0182..8edf487 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -185,11 +185,30 @@ static inline u64 sched_rt_period(struct rt_rq *rt_rq) typedef struct task_group *rt_rq_iter_t; -#define for_each_rt_rq(rt_rq, iter, rq) \ - for (iter = list_entry_rcu(task_groups.next, typeof(*iter), list); \ - (&iter->list != &task_groups) && \ - (rt_rq = iter->rt_rq[cpu_of(rq)]); \ - iter = list_entry_rcu(iter->list.next, typeof(*iter), list)) +/* autogroup is not related to rt group, skip it */ +#define find_first_valid_task_group(iter) \ + ({ \ + list_for_each_entry_rcu(iter, &task_groups, list) \ + if (!task_group_is_autogroup(iter)) \ + break; \ + iter; \ + }) + +#define find_next_valid_task_group(iter) \ + ({ \ + do { \ + iter = list_entry_rcu(iter->list.next, \ + typeof(*iter), list); \ + } while (&iter->list != &task_groups && \ + task_group_is_autogroup(iter)); \ + iter; \ + }) + +#define for_each_rt_rq(rt_rq, iter, rq) \ + for (find_first_valid_task_group(iter); \ + (&iter->list != &task_groups) && \ + (rt_rq = iter->rt_rq[cpu_of(rq)]); \ + find_next_valid_task_group(iter)) static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq) { -- 1.7.4.1