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>,
Josh Poimboeuf <jpoimboe@kernel.org>,
x86@kernel.org, Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@kernel.org>,
Arnaldo Carvalho de Melo <acme@kernel.org>,
Indu Bhagat <indu.bhagat@oracle.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
Ian Rogers <irogers@google.com>,
Adrian Hunter <adrian.hunter@intel.com>,
linux-perf-users@vger.kernel.org, Mark Brown <broonie@kernel.org>,
linux-toolchains@vger.kernel.org, Jordan Rome <jordalgo@meta.com>,
Sam James <sam@gentoo.org>,
Andrii Nakryiko <andrii.nakryiko@gmail.com>,
Jens Remus <jremus@linux.ibm.com>,
Florian Weimer <fweimer@redhat.com>,
Andy Lutomirski <luto@kernel.org>, Weinan Liu <wnliu@google.com>,
Blake Jones <blakejones@google.com>,
Beau Belgrave <beaub@linux.microsoft.com>,
"Jose E. Marchesi" <jemarch@gnu.org>,
Alexander Aring <aahringo@redhat.com>
Subject: [PATCH v5 4/9] tracing: Do not bother getting user space stacktraces for kernel threads
Date: Thu, 24 Apr 2025 15:25:00 -0400 [thread overview]
Message-ID: <20250424192613.014380756@goodmis.org> (raw)
In-Reply-To: 20250424192456.851953422@goodmis.org
From: Steven Rostedt <rostedt@goodmis.org>
If a user space stacktrace is requested when running a kernel thread, just
return, as there's no point trying to get the user space stacktrace as
there is no user space.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
kernel/trace/trace.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 8ddf6b17215c..523e98cd121d 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3087,6 +3087,10 @@ ftrace_trace_userstack(struct trace_array *tr,
if (!(tr->trace_flags & TRACE_ITER_USERSTACKTRACE))
return;
+ /* No point doing user space stacktraces on kernel threads */
+ if (current->flags & PF_KTHREAD)
+ return;
+
/*
* NMIs can not handle page faults, even with fix ups.
* The save user stack can (and often does) fault.
--
2.47.2
next prev parent reply other threads:[~2025-04-24 19:24 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-04-24 19:24 [PATCH v5 0/9] tracing: Deferred unwinding of user space stack traces Steven Rostedt
2025-04-24 19:24 ` [PATCH v5 1/9] unwind_user/deferred: Add deferred unwinding interface Steven Rostedt
2025-04-24 19:24 ` [PATCH v5 2/9] unwind_user/deferred: Make unwind deferral requests NMI-safe Steven Rostedt
2025-04-24 19:24 ` [PATCH v5 3/9] unwind deferred: Use bitmask to determine which callbacks to call Steven Rostedt
2025-04-28 16:33 ` Mathieu Desnoyers
2025-04-28 16:56 ` Steven Rostedt
2025-04-28 18:00 ` Mathieu Desnoyers
2025-04-28 18:12 ` Steven Rostedt
2025-04-28 18:13 ` Mathieu Desnoyers
2025-04-24 19:25 ` Steven Rostedt [this message]
2025-04-24 19:25 ` [PATCH v5 5/9] tracing: Rename __dynamic_array() to __dynamic_field() for ftrace events Steven Rostedt
2025-04-24 19:25 ` [PATCH v5 6/9] tracing: Implement deferred user space stacktracing Steven Rostedt
2025-04-24 19:25 ` [PATCH v5 7/9] mm: Add guard for mmap_read_lock Steven Rostedt
2025-04-24 19:25 ` [PATCH v5 8/9] tracing: Have deferred user space stacktrace show file offsets Steven Rostedt
2025-04-24 19:25 ` [PATCH v5 9/9] tracing: Show inode and device major:minor in deferred user space stacktrace Steven Rostedt
2025-04-24 19:29 ` [PATCH v5 0/9] tracing: Deferred unwinding of user space stack traces Steven Rostedt
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