From: Daniel Bristot de Oliveira <bristot@redhat.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Phil Auld <pauld@redhat.com>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
Kate Carcia <kcarcia@redhat.com>,
Daniel Bristot de Oliveira <bristot@redhat.com>,
Jonathan Corbet <corbet@lwn.net>, Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
Alexandre Chartre <alexandre.chartre@oracle.com>,
Clark Willaims <williams@redhat.com>,
John Kacur <jkacur@redhat.com>,
Juri Lelli <juri.lelli@redhat.com>,
Borislav Petkov <bp@alien8.de>, "H. Peter Anvin" <hpa@zytor.com>,
x86@kernel.org, linux-doc@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH V5 12/14] trace: Protect tr->tracing_cpumask with get/put_online_cpus
Date: Tue, 22 Jun 2021 16:42:30 +0200 [thread overview]
Message-ID: <38d2ef13b33c42fcf424a6213a27c8b5246548e0.1624372313.git.bristot@redhat.com> (raw)
In-Reply-To: <cover.1624372313.git.bristot@redhat.com>
In preparation to the hotplug support on tracers with workload,
protect tr->tracing_cpumask with get/put_online_cpus() to avoid
concurrency with hotplug operations.
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexandre Chartre <alexandre.chartre@oracle.com>
Cc: Clark Willaims <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
---
kernel/trace/trace.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 52fc9438b7b4..c14f33db147e 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -5053,7 +5053,13 @@ int tracing_set_cpumask(struct trace_array *tr,
arch_spin_unlock(&tr->max_lock);
local_irq_enable();
+ /*
+ * tracing_cpumask is read by tracers that support CPU
+ * hotplug.
+ */
+ get_online_cpus();
cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new);
+ put_online_cpus();
return 0;
}
--
2.31.1
next prev parent reply other threads:[~2021-06-22 14:45 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-22 14:42 [PATCH V5 00/14] hwlat improvements and osnoise/timerlat tracers Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 01/14] trace/hwlat: Fix Clark's email Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 02/14] trace/hwlat: Implement the mode config option Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 03/14] trace/hwlat: Switch disable_migrate to mode none Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 04/14] trace/hwlat: Implement the per-cpu mode Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 05/14] trace: Add a generic function to read/write u64 values from tracefs Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 06/14] trace/hwlat: Use trace_min_max_param for width and window params Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 07/14] trace/hwlat: Remove printk from sampling loop Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 08/14] trace: Add __print_ns_to_secs() and __print_ns_without_secs() helpers Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 09/14] trace: Add osnoise tracer Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 10/14] trace: Add timerlat tracer Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 11/14] trace/hwlat: Protect kdata->kthread with get/put_online_cpus Daniel Bristot de Oliveira
2021-06-22 14:42 ` Daniel Bristot de Oliveira [this message]
2021-06-24 21:39 ` [PATCH V5 12/14] trace: Protect tr->tracing_cpumask " Steven Rostedt
2021-06-25 4:34 ` Daniel Bristot de Oliveira
2021-06-25 9:27 ` Peter Zijlstra
2021-06-25 9:31 ` Sebastian Andrzej Siewior
2021-06-22 14:42 ` [PATCH V5 13/14] trace/hwlat: Support hotplug operations Daniel Bristot de Oliveira
2021-06-22 14:42 ` [PATCH V5 14/14] trace/osnoise: " Daniel Bristot de Oliveira
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