From: "Paul E. McKenney" <paulmck@kernel.org>
To: frederic@kernel.org, rcu@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, kernel-team@meta.com,
rostedt@goodmis.org, "Paul E. McKenney" <paulmck@kernel.org>
Subject: [PATCH rcu 3/5] refscale: Correct affinity check
Date: Wed, 9 Oct 2024 11:02:51 -0700 [thread overview]
Message-ID: <20241009180253.777965-3-paulmck@kernel.org> (raw)
In-Reply-To: <51cccc37-5139-497c-92e3-6a20e17939a1@paulmck-laptop>
The current affinity check works fine until there are more reader
processes than CPUs, at which point the affinity check is looking for
non-existent CPUs. This commit therefore applies the same modulus to
the check as is present in the set_cpus_allowed_ptr() call.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
kernel/rcu/refscale.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/rcu/refscale.c b/kernel/rcu/refscale.c
index 639d1cfc657b2..af32331ef645a 100644
--- a/kernel/rcu/refscale.c
+++ b/kernel/rcu/refscale.c
@@ -863,7 +863,7 @@ ref_scale_reader(void *arg)
goto end;
// Make sure that the CPU is affinitized appropriately during testing.
- WARN_ON_ONCE(raw_smp_processor_id() != me);
+ WARN_ON_ONCE(raw_smp_processor_id() != me % nr_cpu_ids);
WRITE_ONCE(rt->start_reader, 0);
if (!atomic_dec_return(&n_started))
--
2.40.1
next prev parent reply other threads:[~2024-10-09 18:02 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-10-09 18:02 [PATCH rcu 0/5] Torture-test changes for v6.13 Paul E. McKenney
2024-10-09 18:02 ` [PATCH rcu 1/5] refscale: Add test for sched_clock() Paul E. McKenney
2024-10-09 18:02 ` [PATCH rcu 2/5] torture: Add --no-affinity parameter to kvm.sh Paul E. McKenney
2024-10-09 18:02 ` Paul E. McKenney [this message]
2024-10-09 18:02 ` [PATCH rcu 4/5] rcuscale: Add guest_os_delay module parameter Paul E. McKenney
2024-10-09 18:02 ` [PATCH rcu 5/5] rcutorture: Avoid printing cpu=-1 for no-fault RCU boost failure 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=20241009180253.777965-3-paulmck@kernel.org \
--to=paulmck@kernel.org \
--cc=frederic@kernel.org \
--cc=kernel-team@meta.com \
--cc=linux-kernel@vger.kernel.org \
--cc=rcu@vger.kernel.org \
--cc=rostedt@goodmis.org \
/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