From: "Paul E. McKenney" <paulmck@kernel.org>
To: rcu@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, kernel-team@meta.com,
rostedt@goodmis.org,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
"Paul E. McKenney" <paulmck@kernel.org>
Subject: [PATCH RFC 4/4] hazptrtorture: Enable system-independent CPU overcommit
Date: Thu, 7 May 2026 09:51:13 -0700 [thread overview]
Message-ID: <20260507165113.2039524-4-paulmck@kernel.org> (raw)
In-Reply-To: <5bfe6ac9-432e-43b8-8290-59ca249b0f80@paulmck-laptop>
This commit interprets negative values of the nreaders module parameter
as a number of readers per CPU, so that hazptrtorture.nreaders=-5 would
spawn five hazard-pointer reader kthreads per CPU.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
kernel/rcu/hazptrtorture.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/rcu/hazptrtorture.c b/kernel/rcu/hazptrtorture.c
index 219fd90a7f8840..c266d0b64dfde1 100644
--- a/kernel/rcu/hazptrtorture.c
+++ b/kernel/rcu/hazptrtorture.c
@@ -631,7 +631,7 @@ static int __init hazptr_torture_init(void)
if (nreaders >= 0) {
nrealreaders = nreaders;
} else {
- nrealreaders = num_online_cpus() - 2 - nreaders;
+ nrealreaders = num_online_cpus() * -nreaders;
if (nrealreaders <= 0)
nrealreaders = 1;
}
--
2.40.1
prev parent reply other threads:[~2026-05-07 16:51 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-07 16:50 [PATCH RFC 0/4] Hazard-pointer torture test Paul E. McKenney
2026-05-07 16:51 ` [PATCH RFC 1/4] torture: Add a hazptrtorture.c " Paul E. McKenney
2026-05-07 16:51 ` [PATCH RFC 2/4] hazptrtorture: Add testing of on-stack hazptr_ctx structures Paul E. McKenney
2026-05-07 16:51 ` [PATCH RFC 3/4] hazptrtorture: Add microsecond-scale sleep in readers Paul E. McKenney
2026-05-07 16:51 ` Paul E. McKenney [this message]
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