From 9059393e4ec1c8c6623a120b405ef2c90b968d80 Mon Sep 17 00:00:00 2001 From: Vincent Guittot Date: Wed, 17 May 2017 11:50:45 +0200 Subject: sched/fair: Use reweight_entity() for set_user_nice() Now that we directly change load_avg and propagate that change into the sums, sys_nice() and co should do the same, otherwise its possible to confuse load accounting when we migrate near the weight change. Fixes-by: Josef Bacik Signed-off-by: Vincent Guittot [ Added changelog, fixed the call condition. ] Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/20170517095045.GA8420@linaro.org Signed-off-by: Ingo Molnar --- kernel/sched/core.c | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) (limited to 'kernel/sched/core.c') diff --git a/kernel/sched/core.c b/kernel/sched/core.c index d17c5da523a0..2288a145bf01 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -733,7 +733,7 @@ int tg_nop(struct task_group *tg, void *data) } #endif -static void set_load_weight(struct task_struct *p) +static void set_load_weight(struct task_struct *p, bool update_load) { int prio = p->static_prio - MAX_RT_PRIO; struct load_weight *load = &p->se.load; @@ -747,8 +747,16 @@ static void set_load_weight(struct task_struct *p) return; } - load->weight = scale_load(sched_prio_to_weight[prio]); - load->inv_weight = sched_prio_to_wmult[prio]; + /* + * SCHED_OTHER tasks have to update their load when changing their + * weight + */ + if (update_load && p->sched_class == &fair_sched_class) { + reweight_task(p, prio); + } else { + load->weight = scale_load(sched_prio_to_weight[prio]); + load->inv_weight = sched_prio_to_wmult[prio]; + } } static inline void enqueue_task(struct rq *rq, struct task_struct *p, int flags) @@ -2358,7 +2366,7 @@ int sched_fork(unsigned long clone_flags, struct task_struct *p) p->static_prio = NICE_TO_PRIO(0); p->prio = p->normal_prio = __normal_prio(p); - set_load_weight(p); + set_load_weight(p, false); /* * We don't need the reset flag anymore after the fork. It has @@ -3805,7 +3813,7 @@ void set_user_nice(struct task_struct *p, long nice) put_prev_task(rq, p); p->static_prio = NICE_TO_PRIO(nice); - set_load_weight(p); + set_load_weight(p, true); old_prio = p->prio; p->prio = effective_prio(p); delta = p->prio - old_prio; @@ -3962,7 +3970,7 @@ static void __setscheduler_params(struct task_struct *p, */ p->rt_priority = attr->sched_priority; p->normal_prio = normal_prio(p); - set_load_weight(p); + set_load_weight(p, true); } /* Actually do priority change: must hold pi & rq lock. */ @@ -5933,7 +5941,7 @@ void __init sched_init(void) atomic_set(&rq->nr_iowait, 0); } - set_load_weight(&init_task); + set_load_weight(&init_task, false); /* * The boot idle thread does lazy MMU switching as well: -- cgit