The following commit has been merged into the sched/fifo branch of tip:
Commit-ID: b1433395c4cc078b4382429e6d7dd1721714094f
Gitweb: https://git.kernel.org/tip/b1433395c4cc078b4382429e6d7dd1721714094f
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Tue, 21 Apr 2020 12:09:13 +02:00
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Mon, 15 Jun 2020 14:10:24 +02:00
sched,rcuperf: Convert to sched_set_fifo_low()
Because SCHED_FIFO is a broken scheduler model (see previous patches)
take away the priority field, the kernel can't possibly make an
informed decision.
Effectively no change.
Cc: paulmck@xxxxxxxxxx
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Ingo Molnar <mingo@xxxxxxxxxx>
Reviewed-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
kernel/rcu/rcuperf.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/kernel/rcu/rcuperf.c b/kernel/rcu/rcuperf.c
index 16dd1e6..64249a0 100644
--- a/kernel/rcu/rcuperf.c
+++ b/kernel/rcu/rcuperf.c
@@ -354,7 +354,6 @@ rcu_perf_writer(void *arg)
int i_max;
long me = (long)arg;
struct rcu_head *rhp = NULL;
- struct sched_param sp;
bool started = false, done = false, alldone = false;
u64 t;
u64 *wdp;
@@ -363,8 +362,7 @@ rcu_perf_writer(void *arg)
VERBOSE_PERFOUT_STRING("rcu_perf_writer task started");
WARN_ON(!wdpp);
set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids));
- sp.sched_priority = 1;
- sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
+ sched_set_fifo_low(current);
if (holdoff)
schedule_timeout_uninterruptible(holdoff * HZ);
@@ -420,9 +418,7 @@ retry:
started = true;
if (!done && i >= MIN_MEAS) {
done = true;
- sp.sched_priority = 0;
- sched_setscheduler_nocheck(current,
- SCHED_NORMAL, &sp);
+ sched_set_normal(current, 0);
pr_alert("%s%s rcu_perf_writer %ld has %d measurements\n",
perf_type, PERF_FLAG, me, MIN_MEAS);
if (atomic_inc_return(&n_rcu_perf_writer_finished) >=
|