From: Steven Rostedt <rostedt@goodmis.org>
To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Andrew Morton <akpm@linux-foundation.org>
Subject: [PATCH 07/12] tracing: Do not use per CPU array_buffer.data->disabled for cpumask
Date: Fri, 02 May 2025 16:51:54 -0400 [thread overview]
Message-ID: <20250502205348.972501388@goodmis.org> (raw)
In-Reply-To: 20250502205147.283272733@goodmis.org
From: Steven Rostedt <rostedt@goodmis.org>
The per CPU "disabled" value was the original way to disable tracing when
the tracing subsystem was first created. Today, the ring buffer
infrastructure has its own way to disable tracing. In fact, things have
changed so much since 2008 that many things ignore the disable flag.
Do not bother setting the per CPU disabled flag of the array_buffer data
to use to determine what CPUs can write to the buffer and only rely on the
ring buffer code itself to disabled it.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
kernel/trace/trace.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index bae32778b292..8cee71683fe3 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -5048,7 +5048,6 @@ int tracing_set_cpumask(struct trace_array *tr,
*/
if (cpumask_test_cpu(cpu, tr->tracing_cpumask) &&
!cpumask_test_cpu(cpu, tracing_cpumask_new)) {
- atomic_inc(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled);
ring_buffer_record_disable_cpu(tr->array_buffer.buffer, cpu);
#ifdef CONFIG_TRACER_MAX_TRACE
ring_buffer_record_disable_cpu(tr->max_buffer.buffer, cpu);
@@ -5056,7 +5055,6 @@ int tracing_set_cpumask(struct trace_array *tr,
}
if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) &&
cpumask_test_cpu(cpu, tracing_cpumask_new)) {
- atomic_dec(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled);
ring_buffer_record_enable_cpu(tr->array_buffer.buffer, cpu);
#ifdef CONFIG_TRACER_MAX_TRACE
ring_buffer_record_enable_cpu(tr->max_buffer.buffer, cpu);
--
2.47.2
next prev parent reply other threads:[~2025-05-02 20:53 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-05-02 20:51 [PATCH 00/12] tracing: Remove most uses of "disabled" field Steven Rostedt
2025-05-02 20:51 ` [PATCH 01/12] tracing/mmiotrace: Remove reference to unused per CPU data pointer Steven Rostedt
2025-05-02 20:51 ` [PATCH 02/12] tracing: Do not bother setting "disabled" field for ftrace_dump_one() Steven Rostedt
2025-05-02 20:51 ` [PATCH 03/12] ftrace: Do not bother checking per CPU "disabled" flag Steven Rostedt
2025-05-02 20:51 ` [PATCH 04/12] tracing: Just use this_cpu_read() to access ignore_pid Steven Rostedt
2025-05-02 20:51 ` [PATCH 05/12] tracing: kdb: Use tracer_tracing_on/off() instead of setting per CPU disabled Steven Rostedt
2025-05-05 5:05 ` kernel test robot
2025-05-05 15:42 ` Doug Anderson
2025-05-05 15:59 ` Steven Rostedt
2025-05-02 20:51 ` [PATCH 06/12] ftrace: Do not disabled function graph based on "disabled" field Steven Rostedt
2025-05-02 20:51 ` Steven Rostedt [this message]
2025-05-02 20:51 ` [PATCH 08/12] ring-buffer: Add ring_buffer_record_is_on_cpu() Steven Rostedt
2025-05-02 20:51 ` [PATCH 09/12] tracing: branch: Use trace_tracing_is_on_cpu() instead of "disabled" field Steven Rostedt
2025-05-03 10:10 ` kernel test robot
2025-05-05 12:11 ` kernel test robot
2025-05-02 20:51 ` [PATCH 10/12] tracing: Convert the per CPU "disabled" counter to local from atomic Steven Rostedt
2025-05-02 20:51 ` [PATCH 11/12] tracing: Use atomic_inc_return() for updating "disabled" counter in irqsoff tracer Steven Rostedt
2025-05-02 20:51 ` [PATCH 12/12] tracing: Remove unused buffer_page field from trace_array_cpu structure Steven Rostedt
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