From: Stephen Rothwell <sfr@canb.auug.org.au>
To: "Paul E. McKenney" <paulmck@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
"H. Peter Anvin" <hpa@zytor.com>,
Peter Zijlstra <peterz@infradead.org>
Cc: Linux Next Mailing List <linux-next@vger.kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
"Joel Fernandes (Google)" <joel@joelfernandes.org>
Subject: Re: linux-next: manual merge of the rcu tree with the tip tree
Date: Fri, 29 May 2020 16:41:32 +1000 [thread overview]
Message-ID: <20200529164132.6fb46471@canb.auug.org.au> (raw)
In-Reply-To: <20200529162234.4f1c3d58@canb.auug.org.au>
[-- Attachment #1: Type: text/plain, Size: 2736 bytes --]
Hi all,
On Fri, 29 May 2020 16:22:34 +1000 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
> Hi all,
>
> Today's linux-next merge of the rcu tree got a conflict in:
>
> kernel/rcu/tree.c
>
> between commits:
>
> 806f04e9fd2c ("rcu: Allow for smp_call_function() running callbacks from idle")
> aaf2bc50df1f ("rcu: Abstract out rcu_irq_enter_check_tick() from rcu_nmi_enter()")
>
> from the tip tree and commit:
>
> c0601bb42994 ("rcu/tree: Clean up dynticks counter usage")
> 3f3baaf3ac07 ("rcu/tree: Remove dynticks_nmi_nesting counter")
>
> from the rcu tree.
>
> I fixed it up (I punted and took some from the former and some from the
> latter) and can carry the fix as necessary. This is now fixed as far as
> linux-next is concerned, but any non trivial conflicts should be mentioned
> to your upstream maintainer when your tree is submitted for merging.
> You may also want to consider cooperating with the maintainer of the
> conflicting tree to minimise any particularly complex conflicts.
I redid this and the resolution is below, but you should look at the
final file when I do the release.
--
Cheers,
Stephen Rothwell
diff --cc kernel/rcu/tree.c
index c716eadc7617,78125749638f..1426b968eec1
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@@ -427,14 -385,8 +386,12 @@@ EXPORT_SYMBOL_GPL(rcu_momentary_dyntick
*/
static int rcu_is_cpu_rrupt_from_idle(void)
{
- long nesting;
-
- /* Called only from within the scheduling-clock interrupt */
- lockdep_assert_in_irq();
+ /*
+ * Usually called from the tick; but also used from smp_function_call()
+ * for expedited grace periods. This latter can result in running from
+ * the idle task, instead of an actual IPI.
+ */
+ lockdep_assert_irqs_disabled();
/* Check for counter underflows */
RCU_LOCKDEP_WARN(__this_cpu_read(rcu_data.dynticks_nesting) < 0,
@@@ -778,24 -718,6 +723,21 @@@ void rcu_irq_exit_preempt(void
"RCU in extended quiescent state!");
}
+#ifdef CONFIG_PROVE_RCU
+/**
+ * rcu_irq_exit_check_preempt - Validate that scheduling is possible
+ */
+void rcu_irq_exit_check_preempt(void)
+{
+ lockdep_assert_irqs_disabled();
+
+ RCU_LOCKDEP_WARN(__this_cpu_read(rcu_data.dynticks_nesting) <= 0,
+ "RCU dynticks_nesting counter underflow/zero!");
- RCU_LOCKDEP_WARN(__this_cpu_read(rcu_data.dynticks_nmi_nesting) !=
- DYNTICK_IRQ_NONIDLE,
- "Bad RCU dynticks_nmi_nesting counter\n");
+ RCU_LOCKDEP_WARN(rcu_dynticks_curr_cpu_in_eqs(),
+ "RCU in extended quiescent state!");
+}
+#endif /* #ifdef CONFIG_PROVE_RCU */
+
/*
* Wrapper for rcu_irq_exit() where interrupts are enabled.
*
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 488 bytes --]
next prev parent reply other threads:[~2020-05-29 6:41 UTC|newest]
Thread overview: 71+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-29 6:22 linux-next: manual merge of the rcu tree with the tip tree Stephen Rothwell
2020-05-29 6:41 ` Stephen Rothwell [this message]
2020-05-29 14:15 ` Paul E. McKenney
2020-05-29 23:38 ` Stephen Rothwell
-- strict thread matches above, loose matches on Subject: below --
2024-02-27 1:55 Stephen Rothwell
2022-04-06 2:45 Stephen Rothwell
2022-04-06 16:28 ` Paul E. McKenney
2022-02-21 18:17 broonie
2021-10-12 4:48 Stephen Rothwell
2021-10-13 16:31 ` Paul E. McKenney
2021-08-17 7:09 Stephen Rothwell
2021-06-23 5:33 Stephen Rothwell
2021-06-22 4:51 Stephen Rothwell
2021-06-22 4:47 Stephen Rothwell
2021-06-22 5:04 ` Stephen Rothwell
2021-06-22 17:10 ` Paul E. McKenney
2020-10-09 4:59 Stephen Rothwell
2020-07-29 6:23 Stephen Rothwell
2020-06-26 3:14 Stephen Rothwell
2020-06-25 2:44 Stephen Rothwell
2020-06-25 3:44 ` Paul E. McKenney
2020-06-24 3:04 Stephen Rothwell
2020-06-24 4:06 ` Paul E. McKenney
2020-03-25 3:08 Stephen Rothwell
2020-03-25 3:18 ` Paul E. McKenney
2020-03-25 21:31 ` Paul E. McKenney
2019-12-19 0:50 Stephen Rothwell
2019-12-19 1:27 ` Paul E. McKenney
2019-12-19 1:31 ` Paul E. McKenney
2019-12-19 8:41 ` Peter Zijlstra
2019-12-19 13:38 ` Paul E. McKenney
2019-12-16 23:37 Stephen Rothwell
2018-06-22 2:27 Stephen Rothwell
2018-06-26 19:33 ` Paul E. McKenney
2017-11-10 2:14 Stephen Rothwell
2017-08-22 4:13 Stephen Rothwell
2017-07-31 3:50 Stephen Rothwell
2017-07-31 16:13 ` Paul E. McKenney
2017-08-01 0:04 ` Mathieu Desnoyers
2017-08-01 4:03 ` Paul E. McKenney
2017-08-01 4:25 ` Mathieu Desnoyers
2017-08-01 16:31 ` Paul E. McKenney
2017-08-01 13:43 ` Andy Lutomirski
2017-08-01 13:58 ` Peter Zijlstra
2017-08-01 14:15 ` Peter Zijlstra
2017-08-01 14:17 ` Andy Lutomirski
2017-08-01 14:02 ` Mathieu Desnoyers
2017-08-01 14:15 ` Andy Lutomirski
2017-08-01 15:40 ` Mathieu Desnoyers
2017-08-01 21:36 ` Paul E. McKenney
2016-07-18 5:26 Stephen Rothwell
2016-07-19 3:00 ` Paul E. McKenney
2016-06-09 5:14 Stephen Rothwell
2016-06-09 15:59 ` Paul E. McKenney
2016-03-04 4:13 Stephen Rothwell
2016-03-04 15:04 ` Paul E. McKenney
2015-07-16 2:57 Stephen Rothwell
2015-05-07 3:56 Stephen Rothwell
2014-02-24 4:18 Stephen Rothwell
2014-02-24 4:42 ` Paul E. McKenney
2012-09-05 3:59 Stephen Rothwell
2012-09-05 16:39 ` Paul E. McKenney
2012-09-05 17:11 ` Peter Zijlstra
2012-08-23 3:01 Stephen Rothwell
2012-08-23 3:22 ` Paul E. McKenney
2012-08-22 4:27 Stephen Rothwell
2012-08-22 5:05 ` Paul E. McKenney
2012-08-22 4:27 Stephen Rothwell
2012-08-22 5:03 ` Paul E. McKenney
2011-06-20 4:47 Stephen Rothwell
2011-06-20 15:17 ` Paul E. McKenney
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=20200529164132.6fb46471@canb.auug.org.au \
--to=sfr@canb.auug.org.au \
--cc=hpa@zytor.com \
--cc=joel@joelfernandes.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-next@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=paulmck@kernel.org \
--cc=peterz@infradead.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).