2021-06-09 00:56:06

by Frederic Weisbecker

Subject: [PATCH 0/2] sched: Define default preempt dynamic boot mode on Kconfig

Make life easier for distros and automatic kernel robot testing.

git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
sched/core

HEAD: 54b77d028543df2d5b091b5542e68e5fe2dca1b8

Thanks,
Frederic
---

Frederic Weisbecker (2):
sched: Add default dynamic preempt mode Kconfig
sched: Always print out preempt dynamic state


kernel/Kconfig.preempt | 53 ++++++++++++++++++++++++++++++++++++++++++++++++++
kernel/sched/core.c | 40 +++++++++++++++++++++++++++++++++----
2 files changed, 89 insertions(+), 4 deletions(-)

2021-06-09 00:56:07

by Frederic Weisbecker

Subject: [PATCH 2/2] sched: Always print out preempt dynamic state

Previously the preempt dynamic mode wasn't printed out if it wasn't
overriden with the "preempt=" boot option.

But now that the default preempt dynamic behaviour can be selected at
Kconfig time, we can't assume anymore that preempt=full is the default.
The only way to retrieve that information is to browse the kernel config
file.

Better print it out unconditionally then.

Signed-off-by: Frederic Weisbecker <[email protected]>
---
kernel/sched/core.c | 21 ++++++++++++++++-----
1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index df47a8275c37..6b883adad8f7 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6262,6 +6262,21 @@ int sched_dynamic_mode(const char *str)

void sched_dynamic_update(int mode)
{
+ switch (mode) {
+ case preempt_dynamic_none:
+ pr_info("Dynamic Preempt: none\n");
+ break;
+ case preempt_dynamic_voluntary:
+ pr_info("Dynamic Preempt: voluntary\n");
+ break;
+ case preempt_dynamic_full:
+ pr_info("Dynamic Preempt: full\n");
+ break;
+ default:
+ pr_info("Dynamic Preempt: incorrect\n");
+ return;
+ }
+
if (preempt_dynamic_mode == mode)
return;

@@ -6282,7 +6297,6 @@ void sched_dynamic_update(int mode)
static_call_update(preempt_schedule, NULL);
static_call_update(preempt_schedule_notrace, NULL);
static_call_update(irqentry_exit_cond_resched, NULL);
- pr_info("Dynamic Preempt: none\n");
break;

case preempt_dynamic_voluntary:
@@ -6291,7 +6305,6 @@ void sched_dynamic_update(int mode)
static_call_update(preempt_schedule, NULL);
static_call_update(preempt_schedule_notrace, NULL);
static_call_update(irqentry_exit_cond_resched, NULL);
- pr_info("Dynamic Preempt: voluntary\n");
break;

case preempt_dynamic_full:
@@ -6300,7 +6313,6 @@ void sched_dynamic_update(int mode)
static_call_update(preempt_schedule, __preempt_schedule_func);
static_call_update(preempt_schedule_notrace, __preempt_schedule_notrace_func);
static_call_update(irqentry_exit_cond_resched, irqentry_exit_cond_resched);
- pr_info("Dynamic Preempt: full\n");
break;
}

@@ -6323,8 +6335,7 @@ __setup("preempt=", setup_preempt_mode);

static void __init init_preempt(void)
{
- if (preempt_dynamic_mode_init != preempt_dynamic_full)
- sched_dynamic_update(preempt_dynamic_mode_init);
+ sched_dynamic_update(preempt_dynamic_mode_init);
}
#else
static inline void init_preempt(void) { }
--
2.25.1