From: Frederic Weisbecker <frederic@kernel.org>
To: Peter Zijlstra <peterz@infradead.org>,
"Paul E . McKenney" <paulmck@kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
Frederic Weisbecker <frederic@kernel.org>,
"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
Ingo Molnar <mingo@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
stable@vger.kernel.org
Subject: [RFC PATCH 2/8] rcu: Pull deferred rcuog wake up to rcu_eqs_enter() callers
Date: Sat, 9 Jan 2021 03:05:30 +0100 [thread overview]
Message-ID: <20210109020536.127953-3-frederic@kernel.org> (raw)
In-Reply-To: <20210109020536.127953-1-frederic@kernel.org>
Deferred wakeup of rcuog kthreads upon RCU idle mode entry is going to
be handled differently whether initiated by idle, user or guest. Prepare
with pulling that control up to rcu_eqs_enter() callers.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar<mingo@kernel.org>
---
kernel/rcu/tree.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index fef90c467670..b9fff18d14d9 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -643,7 +643,6 @@ static noinstr void rcu_eqs_enter(bool user)
instrumentation_begin();
trace_rcu_dyntick(TPS("Start"), rdp->dynticks_nesting, 0, atomic_read(&rdp->dynticks));
WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !user && !is_idle_task(current));
- do_nocb_deferred_wakeup(rdp);
rcu_prepare_for_idle();
rcu_preempt_deferred_qs(current);
@@ -671,7 +670,10 @@ static noinstr void rcu_eqs_enter(bool user)
*/
void rcu_idle_enter(void)
{
+ struct rcu_data *rdp = this_cpu_ptr(&rcu_data);
+
lockdep_assert_irqs_disabled();
+ do_nocb_deferred_wakeup(rdp);
rcu_eqs_enter(false);
}
EXPORT_SYMBOL_GPL(rcu_idle_enter);
@@ -690,7 +692,10 @@ EXPORT_SYMBOL_GPL(rcu_idle_enter);
*/
noinstr void rcu_user_enter(void)
{
+ struct rcu_data *rdp = this_cpu_ptr(&rcu_data);
+
lockdep_assert_irqs_disabled();
+ do_nocb_deferred_wakeup(rdp);
rcu_eqs_enter(true);
}
#endif /* CONFIG_NO_HZ_FULL */
--
2.25.1
next prev parent reply other threads:[~2021-01-09 2:06 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-09 2:05 [RFC PATCH 0/8] rcu/sched: Fix ignored rescheduling after rcu_eqs_enter() v3 Frederic Weisbecker
2021-01-09 2:05 ` [RFC PATCH 1/8] rcu: Remove superfluous rdp fetch Frederic Weisbecker
2021-01-09 9:03 ` Greg KH
2021-01-10 10:59 ` Frederic Weisbecker
2021-01-09 2:05 ` Frederic Weisbecker [this message]
2021-01-09 2:05 ` [RFC PATCH 3/8] rcu/nocb: Perform deferred wake up before last idle's need_resched() check Frederic Weisbecker
2021-01-09 2:05 ` [RFC PATCH 4/8] rcu/nocb: Trigger self-IPI on late deferred wake up before user resume Frederic Weisbecker
2021-01-11 12:04 ` Peter Zijlstra
2021-01-11 12:35 ` Frederic Weisbecker
2021-01-09 2:05 ` [RFC PATCH 5/8] entry: Explicitly flush pending rcuog wakeup before last rescheduling points Frederic Weisbecker
2021-01-11 0:40 ` Frederic Weisbecker
2021-01-11 5:13 ` Paul E. McKenney
2021-01-11 11:50 ` Frederic Weisbecker
2021-01-11 12:08 ` Peter Zijlstra
2021-01-11 12:54 ` Frederic Weisbecker
2021-01-09 2:05 ` [RFC PATCH 6/8] sched: Report local wake up on resched blind zone within idle loop Frederic Weisbecker
2021-01-11 12:25 ` Peter Zijlstra
2021-01-11 12:56 ` Frederic Weisbecker
2021-01-12 8:24 ` [sched] 9720a64438: WARNING:at_kernel/sched/core.c:#sched_resched_local_assert_allowed kernel test robot
[not found] ` <161062476680.19482.8402362019173198799@build.alporthouse.com>
2021-01-14 15:19 ` [RFC PATCH 6/8] sched: Report local wake up on resched blind zone within idle loop Paul E. McKenney
2021-01-09 2:05 ` [RFC PATCH 7/8] entry: Report local wake up on resched blind zone while resuming to user Frederic Weisbecker
2021-01-13 2:46 ` [entry] 8e01c5f104: unixbench.score -2.2% regression kernel test robot
2021-01-09 2:05 ` [RFC PATCH 8/8] timer: Report ignored local enqueue in nohz mode Frederic Weisbecker
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210109020536.127953-3-frederic@kernel.org \
--to=frederic@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=paulmck@kernel.org \
--cc=peterz@infradead.org \
--cc=rafael.j.wysocki@intel.com \
--cc=stable@vger.kernel.org \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).