From: Peter Zijlstra (Intel) <[email protected]>
Not-Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
---
kernel/sched/core.c | 38 +++++++++++++++++++++++++++++++++++++-
1 file changed, 37 insertions(+), 1 deletion(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 0e3c51a1b54a..e8e5f26db052 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -106,6 +106,10 @@ static inline bool __prio_less(struct task_struct *a,
struct task_struct *b, boo
int pa = __task_prio(a), pb = __task_prio(b);
+ trace_printk("(%s/%d;%d,%Lu,%Lu) ?< (%s/%d;%d,%Lu,%Lu)\n",
+ a->comm, a->pid, pa, a->se.vruntime, a->dl.deadline,
+ b->comm, b->pid, pa, b->se.vruntime, b->dl.deadline);
+
if (-pa < -pb)
return true;
@@ -264,6 +268,8 @@ static void __sched_core_enable(void)
static_branch_enable(&__sched_core_enabled);
stop_machine(__sched_core_stopper, (void *)true, NULL);
+
+ printk("core sched enabled\n");
}
static void __sched_core_disable(void)
@@ -272,6 +278,8 @@ static void __sched_core_disable(void)
stop_machine(__sched_core_stopper, (void *)false, NULL);
static_branch_disable(&__sched_core_enabled);
+
+ printk("core sched disabled\n");
}
void sched_core_get(void)
@@ -3706,6 +3714,14 @@ pick_next_task(struct rq *rq, struct task_struct *prev,
struct rq_flags *rf)
put_prev_task(rq, prev);
set_next_task(rq, next);
}
+
+ trace_printk("pick pre selected (%u %u %u): %s/%d %lx\n",
+ rq->core->core_task_seq,
+ rq->core->core_pick_seq,
+ rq->core_sched_seq,
+ next->comm, next->pid,
+ next->core_cookie);
+
return next;
}
@@ -3777,6 +3793,9 @@ pick_next_task(struct rq *rq, struct task_struct *prev,
struct rq_flags *rf)
next = p;
rq->core_pick = NULL;
+ trace_printk("unconstrained pick: %s/%d %lx\n",
+ next->comm, next->pid,
next->core_cookie);
+
/*
* If the sibling is idling, we might want to
wake it
* so that it can check for any runnable tasks
that did
@@ -3787,6 +3806,8 @@ pick_next_task(struct rq *rq, struct task_struct *prev,
struct rq_flags *rf)
rq_j->core_pick = NULL;
if (j != cpu &&
is_idle_task(rq_j->curr) &&
rq_j->nr_running) {
+ trace_printk("IPI(%d->%d[%d])
idle preempt\n",
+ cpu, j,
rq_j->nr_running);
resched_curr(rq_j);
}
}
@@ -3798,6 +3819,9 @@ pick_next_task(struct rq *rq, struct task_struct *prev,
struct rq_flags *rf)
rq_i->core_pick = p;
+ trace_printk("cpu(%d): selected: %s/%d %lx\n",
+ i, p->comm, p->pid, p->core_cookie);
+
/*
* If this new candidate is of higher priority than the
* previous; and they're incompatible; we need to wipe
@@ -3812,6 +3836,8 @@ pick_next_task(struct rq *rq, struct task_struct *prev,
struct rq_flags *rf)
rq->core->core_cookie = p->core_cookie;
max = p;
+ trace_printk("max: %s/%d %lx\n", max->comm,
max->pid, max->core_cookie);
+
if (old_max && !cookie_match(old_max, p)) {
for_each_cpu(j, smt_mask) {
if (j == i)
@@ -3847,13 +3873,17 @@ next_class:;
if (i == cpu)
continue;
- if (rq_i->curr != rq_i->core_pick)
+ if (rq_i->curr != rq_i->core_pick) {
+ trace_printk("IPI(%d)\n", i);
resched_curr(rq_i);
+ }
}
rq->core_sched_seq = rq->core->core_pick_seq;
next = rq->core_pick;
+ trace_printk("picked: %s/%d %lx\n", next->comm, next->pid,
next->core_cookie);
+
done:
set_next_task(rq, next);
return next;
@@ -3890,6 +3920,10 @@ static bool try_steal_cookie(int this, int that)
if (p->core_occupation > dst->idle->core_occupation)
goto next;
+ trace_printk("core fill: %s/%d (%d->%d) %d %d %lx\n",
+ p->comm, p->pid, that, this,
+ p->core_occupation, dst->idle->core_occupation,
cookie);
+
p->on_rq = TASK_ON_RQ_MIGRATING;
deactivate_task(src, p, 0);
set_task_cpu(p, this);
@@ -6471,6 +6505,8 @@ int sched_cpu_starting(unsigned int cpu)
WARN_ON_ONCE(rq->core && rq->core != core_rq);
rq->core = core_rq;
}
+
+ printk("core: %d -> %d\n", cpu, cpu_of(core_rq));
#endif /* CONFIG_SCHED_CORE */
sched_rq_cpu_starting(cpu);
--
2.17.1
