From nobody Wed Oct 8 18:16:17 2025 Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 067162F3C07; Wed, 25 Jun 2025 23:16:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.17 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750893365; cv=none; b=sI5HKXzGhjgl/Ua1sBeWks08Yuqmpj1cpNN3bE+1Bnz75TJBaWsbTAJnKBmiQ1pzeceBIYtuJLZowUkr/5N4sAWx1xg2HrmNATL9aOF4hYQOYs60GijYfU8rJva4HulzCV/q9sxlnn3Px0F13NVQbhsAo/e2WWLun4IE2ZiX6O4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750893365; c=relaxed/simple; bh=c7XmsSRbXS+wdlNfX+ILlqyx+XTp7g6I18Re8KvRp3k=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=I3BtrWx8ue1QqlNSbt0rmiZjefGm54kb2y41KHak1oNhIzzczPTQn1/3rMxMbg9VXr1ZAe5RKxXLRLgDZCyc7cvtNMm2kkoLWyMVrXYZzsrYgy7dW/4NGuisw9ISyhcS0Yvlqt++YQGB5TZU4VgC7ZqFiJWjVDILnv6NCR3bws4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 8653154F51; Wed, 25 Jun 2025 23:16:00 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: nevets@goodmis.org) by omf10.hostedemail.com (Postfix) with ESMTPA id 550D130; Wed, 25 Jun 2025 23:15:57 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.98.2) (envelope-from ) id 1uUZLq-000000044hk-2kfx; Wed, 25 Jun 2025 19:16:22 -0400 Message-ID: <20250625231622.509379386@goodmis.org> User-Agent: quilt/0.68 Date: Wed, 25 Jun 2025 19:15:46 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, bpf@vger.kernel.org, x86@kernel.org Cc: Masami Hiramatsu , Mathieu Desnoyers , Josh Poimboeuf , Peter Zijlstra , Ingo Molnar , Jiri Olsa , Namhyung Kim , Thomas Gleixner , Andrii Nakryiko , Indu Bhagat , "Jose E. Marchesi" , Beau Belgrave , Jens Remus , Linus Torvalds , Andrew Morton , Jens Axboe Subject: [PATCH v11 05/11] perf: Skip user unwind if the task is a kernel thread References: <20250625231541.584226205@goodmis.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Stat-Signature: 3ds84qnymoopxajjbic9e76mxzqfbb4j X-Rspamd-Server: rspamout03 X-Rspamd-Queue-Id: 550D130 X-Session-Marker: 6E657665747340676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1/xANTxVWHo7orD3GNRhF/thAcdperY2as= X-HE-Tag: 1750893357-121383 X-HE-Meta: U2FsdGVkX1+ljfSTKiZ9A/3J61yduk6c+/qDmguQXo60UEZjY9V1claOk+AMbZF2O0x/5sP8cbPPBxfQKvAAGZtWP0ftCmItMdLWhp/dQuzMKWhZcPXRNmMSIDn6PyDVf+wJ/Qfz2ylWD2we1LNA2uy2LDLxMI5hlqbXoq15TwyJzZTuDm5kkw811z19AEByp7VVPHyiBMvX0yoFT8PT3wrcsLlMlRxw9qoLoxwivOXVmwj2RpYY6MV+agxdm/z4veWc5imJ6TgaTyzPLJMWwfuRbtBxWFWKDw3BacumMBMB4D+Bp81TW8VECgrucmF6tDDY/GJUfjYvcjj2ddPIyezbu9aU/g3c5EXI4zIsHAN9J3ZeADB6on2cfdzex3pNLU4HUHZXZg1NvznRl2i6hxlzjKG3Du0r5vTf5p9m6Ok= Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Josh Poimboeuf If the task is not a user thread, there's no user stack to unwind. Signed-off-by: Josh Poimboeuf Signed-off-by: Steven Rostedt (Google) --- kernel/events/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index ae371007a2a6..02ff31af3d8b 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8166,7 +8166,8 @@ struct perf_callchain_entry * perf_callchain(struct perf_event *event, struct pt_regs *regs) { bool kernel =3D !event->attr.exclude_callchain_kernel; - bool user =3D !event->attr.exclude_callchain_user; + bool user =3D !event->attr.exclude_callchain_user && + !(current->flags & PF_KTHREAD); /* Disallow cross-task user callchains. */ bool crosstask =3D event->ctx->task && event->ctx->task !=3D current; const u32 max_stack =3D event->attr.sample_max_stack; --=20 2.47.2