[PATCH 1/2] sched/debug: Inform the number of rt/dl task that can migrate

From: Daniel Bristot de Oliveira
Date: Wed Jun 21 2017 - 15:29:35 EST


Add the value of the rt_rq.rt_nr_migratory and dl_rq.dl_nr_migratory
to the sched_debug output, for instance:

rt_rq[0]:
.rt_nr_running : 2
.rt_nr_migratory : 1 <--- Like this
.rt_throttled : 0
.rt_time : 828.645877
.rt_runtime : 1000.000000

This is useful to debug problems related to the dl/rt schedulers.

This also fixes the format of some variables, that were unsigned, rather
than signed.

[ I am sending this patch to be able to demonstrate ]
[ the problem in the kernel-rt, however, this patch can ]
[ be merged in the vanilla kernel, if people decide it ]
[ is worth having it. ]

Signed-off-by: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
Cc: Luis Claudio R. Goncalves <lgoncalv@xxxxxxxxxx>
Cc: Clark Williams <williams@xxxxxxxxxx>
Cc: Luiz Capitulino <lcapitulino@xxxxxxxxxx>
Cc: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: LKML <linux-kernel@xxxxxxxxxxxxxxx>
Cc: linux-rt-users <linux-rt-users@xxxxxxxxxxxxxxx>
---
kernel/sched/debug.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 0e2af53..2bdeda8 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -552,15 +552,19 @@ void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)

#define P(x) \
SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
+#define PU(x) \
+ SEQ_printf(m, " .%-30s: %lu\n", #x, (unsigned long)(rt_rq->x))
#define PN(x) \
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))

- P(rt_nr_running);
+ PU(rt_nr_running);
+ PU(rt_nr_migratory);
P(rt_throttled);
PN(rt_time);
PN(rt_runtime);

#undef PN
+#undef PU
#undef P
}

@@ -569,7 +573,12 @@ void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq)
struct dl_bw *dl_bw;

SEQ_printf(m, "\ndl_rq[%d]:\n", cpu);
- SEQ_printf(m, " .%-30s: %ld\n", "dl_nr_running", dl_rq->dl_nr_running);
+
+#define PU(x) \
+ SEQ_printf(m, " .%-30s: %lu\n", #x, (unsigned long)(dl_rq->x))
+
+ PU(dl_nr_running);
+ PU(dl_nr_migratory);
#ifdef CONFIG_SMP
dl_bw = &cpu_rq(cpu)->rd->dl_bw;
#else
@@ -577,6 +586,8 @@ void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq)
#endif
SEQ_printf(m, " .%-30s: %lld\n", "dl_bw->bw", dl_bw->bw);
SEQ_printf(m, " .%-30s: %lld\n", "dl_bw->total_bw", dl_bw->total_bw);
+
+#undef PU
}

extern __read_mostly int sched_clock_running;
--
2.9.4