From: Steven Rostedt <rostedt@kernel.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 08/12] tracing: Use system_state in trace_printk_init_buffers()
Date: Fri, 06 Feb 2026 14:37:49 -0500 [thread overview]
Message-ID: <20260206195936.118522327@kernel.org> (raw)
In-Reply-To: 20260206193741.767171392@kernel.org
From: Steven Rostedt <rostedt@goodmis.org>
The function trace_printk_init_buffers() is used to expand tha
trace_printk buffers when trace_printk() is used within the kernel or in
modules. On kernel boot up, it holds off from starting the sched switch
cmdline recorder, but will start it immediately when it is added by a
module.
Currently it uses a trick to see if the global_trace buffer has been
allocated or not to know if it was called by module load or not. But this
is more of a hack, and can not be used when this code is moved out of
trace.c. Instead simply look at the system_state and if it is running then
it is know that it could only be called by module load.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
kernel/trace/trace.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index db36d4aebc15..3b7fa2699301 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3245,10 +3245,9 @@ void trace_printk_init_buffers(void)
/*
* trace_printk_init_buffers() can be called by modules.
* If that happens, then we need to start cmdline recording
- * directly here. If the global_trace.buffer is already
- * allocated here, then this was called by module code.
+ * directly here.
*/
- if (global_trace.array_buffer.buffer)
+ if (system_state == SYSTEM_RUNNING)
tracing_start_cmdline_record();
}
EXPORT_SYMBOL_GPL(trace_printk_init_buffers);
--
2.51.0
next prev parent reply other threads:[~2026-02-06 19:58 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-06 19:37 [PATCH 00/12] tracing: Clean up trace.c and move some code into other files Steven Rostedt
2026-02-06 19:37 ` [PATCH 01/12] tracing: Make tracing_disabled global for tracing system Steven Rostedt
2026-02-06 19:37 ` [PATCH 02/12] tracing: Make tracing_selftest_running global to the tracing subsystem Steven Rostedt
2026-02-06 19:37 ` [PATCH 03/12] tracing: Move __trace_buffer_{un}lock_*() functions to trace.h Steven Rostedt
2026-02-06 19:37 ` [PATCH 04/12] tracing: Move ftrace_trace_stack() out of trace.c and into trace.h Steven Rostedt
2026-02-06 19:37 ` [PATCH 05/12] tracing: Make printk_trace global for tracing system Steven Rostedt
2026-02-06 19:37 ` [PATCH 06/12] tracing: Make tracing_update_buffers() take NULL for global_trace Steven Rostedt
2026-02-06 19:37 ` [PATCH 07/12] tracing: Have trace_printk functions use flags instead of using global_trace Steven Rostedt
2026-02-06 19:37 ` Steven Rostedt [this message]
2026-02-06 19:37 ` [PATCH 09/12] tracing: Move trace_printk functions out of trace.c and into trace_printk.c Steven Rostedt
2026-02-06 19:37 ` [PATCH 10/12] tracing: Move pid filtering into trace_pid.c Steven Rostedt
2026-02-06 19:37 ` [PATCH 11/12] tracing: Move tracing_set_filter_buffering() into trace_events_hist.c Steven Rostedt
2026-02-06 19:37 ` [PATCH 12/12] tracing: Move snapshot code out of trace.c and into trace_snapshot.c Steven Rostedt
2026-02-07 14:56 ` [PATCH 00/12] tracing: Clean up trace.c and move some code into other files Steven Rostedt
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=20260206195936.118522327@kernel.org \
--to=rostedt@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-trace-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=mathieu.desnoyers@efficios.com \
--cc=mhiramat@kernel.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