From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A91EE295500; Wed, 30 Apr 2025 20:01:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746043265; cv=none; b=RCdlJoWDHAfK0okSD+8du54a5nEGotSd6+arxgTgGuyAa6CZImAiVD0ujzzSfvnCit/Q8oyraNQ1H0wPU9D8/5quz8NDdxmEWtHy3pSZ2JesmlqW/quStFdLf6Yc1MxhnVXfQvdQB/l7+D3aQ96yt5wGrx5MvICIYaUudslLrMU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746043265; c=relaxed/simple; bh=wuNRjbmyz6MHvkwS+XtlrPebpFzfrgYzdjwYBw3T+s0=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=PmoJzZQDKTnESk4Yj3WWuibRCF1gV80QnoyPdANnFT06rzuawn5fP4F3+ZLUilMYEJmyckh5eFlu2hqS1k9FjGiWSuS5nUfqq5h5YA2HbbgS5RqiQn6Qnm51jLmQYJLXbG/KjI/WrZxoyzwav6wHbR5yUzX0ozvjPCJc2pla9bI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7C17EC4CEEE; Wed, 30 Apr 2025 20:01:05 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.98.2) (envelope-from ) id 1uADcD-00000001dTb-3SKR; Wed, 30 Apr 2025 16:01:09 -0400 Message-ID: <20250430200109.678557621@goodmis.org> User-Agent: quilt/0.68 Date: Wed, 30 Apr 2025 15:57:59 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Josh Poimboeuf , x86@kernel.org, Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Indu Bhagat , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Ian Rogers , Adrian Hunter , linux-perf-users@vger.kernel.org, Mark Brown , linux-toolchains@vger.kernel.org, Jordan Rome , Sam James , Andrii Nakryiko , Jens Remus , Florian Weimer , Andy Lutomirski , Weinan Liu , Blake Jones , Beau Belgrave , "Jose E. Marchesi" , Alexander Aring Subject: [PATCH v7 13/18] perf: Skip user unwind if the task is a kernel thread. References: <20250430195746.827125963@goodmis.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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 430dd158b1ee..ec9edf602974 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8101,7 +8101,8 @@ struct perf_callchain_entry * perf_callchain(struct perf_event *event, struct pt_regs *regs) { bool kernel = !event->attr.exclude_callchain_kernel; - bool user = !event->attr.exclude_callchain_user; + bool user = !event->attr.exclude_callchain_user && + !(current->flags & PF_KTHREAD); /* Disallow cross-task user callchains. */ bool crosstask = event->ctx->task && event->ctx->task != current; const u32 max_stack = event->attr.sample_max_stack; -- 2.47.2