From: Morten Rasmussen morten.rasmussen@arm.com
Adds ftrace event for tracing task migrations using HMP optimized scheduling.
Signed-off-by: Morten Rasmussen morten.rasmussen@arm.com --- include/trace/events/sched.h | 28 ++++++++++++++++++++++++++++ kernel/sched/fair.c | 15 +++++++++++---- 2 files changed, 39 insertions(+), 4 deletions(-)
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h index 847eb76..501aa32 100644 --- a/include/trace/events/sched.h +++ b/include/trace/events/sched.h @@ -555,6 +555,34 @@ TRACE_EVENT(sched_task_usage_ratio, __entry->comm, __entry->pid, __entry->ratio) ); + +/* + * Tracepoint for HMP (CONFIG_SCHED_HMP) task migrations. + */ +TRACE_EVENT(sched_hmp_migrate, + + TP_PROTO(struct task_struct *tsk, int dest, int force), + + TP_ARGS(tsk, dest, force), + + TP_STRUCT__entry( + __array(char, comm, TASK_COMM_LEN) + __field(pid_t, pid) + __field(int, dest) + __field(int, force) + ), + + TP_fast_assign( + memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN); + __entry->pid = tsk->pid; + __entry->dest = dest; + __entry->force = force; + ), + + TP_printk("comm=%s pid=%d dest=%d force=%d", + __entry->comm, __entry->pid, + __entry->dest, __entry->force) +); #endif /* _TRACE_SCHED_H */
/* This part must be outside protection */ diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 0be53be..811b2b9 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3333,10 +3333,16 @@ unlock: rcu_read_unlock();
#ifdef CONFIG_SCHED_HMP - if (hmp_up_migration(prev_cpu, &p->se)) - return hmp_select_faster_cpu(p, prev_cpu); - if (hmp_down_migration(prev_cpu, &p->se)) - return hmp_select_slower_cpu(p, prev_cpu); + if (hmp_up_migration(prev_cpu, &p->se)) { + new_cpu = hmp_select_faster_cpu(p, prev_cpu); + trace_sched_hmp_migrate(p, new_cpu, 0); + return new_cpu; + } + if (hmp_down_migration(prev_cpu, &p->se)) { + new_cpu = hmp_select_slower_cpu(p, prev_cpu); + trace_sched_hmp_migrate(p, new_cpu, 0); + return new_cpu; + } /* Make sure that the task stays in its previous hmp domain */ if (!cpumask_test_cpu(new_cpu, &hmp_cpu_domain(prev_cpu)->cpus)) return prev_cpu; @@ -5718,6 +5724,7 @@ static void hmp_force_up_migration(int this_cpu) target->push_cpu = hmp_select_faster_cpu(p, cpu); target->migrate_task = p; force = 1; + trace_sched_hmp_migrate(p, target->push_cpu, 1); } } raw_spin_unlock_irqrestore(&target->lock, flags);