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 D3F8C2E7197; Fri, 18 Jul 2025 16:43:00 +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=1752856980; cv=none; b=nu+NeczR1Vjd/5Ziu986rVpfXfYByKqIczi6LZBZbM4+hStK5ewb+LMNwu4HoaHCjxDepirKK3T+xidJgNCBvUSatNyHEBezhDTkGE6PIM9lftcaMlFqPwj+g37QbfzaiskWJ+2EZFE/yg4XFvU5X3uhb4IKvMM/dmKbDSfZD7s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752856980; c=relaxed/simple; bh=PrLV5/6t/jDNDZv13dJ+tk4FMXWbDNxrkHMrhIU764A=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=RO/iC9LGvPlArsPbmeIYnnl5eo9R9qse3T+Gq3NMNCsgizZdhxmVAEZ155BEOAB/towDI9xVioQmblJpMkfqsO0eXb0Ub2IZIlh81xPzb5uplEaeVPdmlVSmmVLGeVs3sH2VIjZN3qzztFhNEUAVxQGwD6ZvsJX5UJf8QM64ki0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TSV60Ani; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TSV60Ani" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 59305C4CEFE; Fri, 18 Jul 2025 16:43:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752856980; bh=PrLV5/6t/jDNDZv13dJ+tk4FMXWbDNxrkHMrhIU764A=; h=Date:From:To:Cc:Subject:References:From; b=TSV60Ani3MuKOzsA0ZrC05OJmgx3B+VpNfAUYCfhwT2YZ4q4C4oR6Ql7bL0nGxS47 AO1iLuFT51LYwUsrwBjj3G0e/k4oo61b3w4ZWluEJ36kVTs6yyhce9LrYhI+TgHa7D VaFL4XD9YyMiQ6T5SRYq3Wj/aUOLWKIXABGzJBh387N2vRSIsjC/c5DVjSwo6Cb+zd a+UYO9/GeuPcV+daYGTCsnibfIB/MWF2NhQMJjI+oDkBTsewGpdjVKK7X5iDCT+vJl eLHPy3iX3ZIyc5AsJDF0UnOw7HCOjHh+X6XyMj5hUINmbktHaCfmRgZQMGKz0OnRk7 /eGc61OOCxN/g== Received: from rostedt by gandalf with local (Exim 4.98.2) (envelope-from ) id 1ucoBA-00000007JYH-0HOh; Fri, 18 Jul 2025 12:43:24 -0400 Message-ID: <20250718164323.918565553@kernel.org> User-Agent: quilt/0.68 Date: Fri, 18 Jul 2025 12:41:24 -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 , Arnaldo Carvalho de Melo , Namhyung Kim , Thomas Gleixner , Andrii Nakryiko , Indu Bhagat , "Jose E. Marchesi" , Beau Belgrave , Jens Remus , Linus Torvalds , Andrew Morton , Jens Axboe , Florian Weimer , Sam James Subject: [PATCH v14 05/11] perf: Skip user unwind if the task is a kernel thread References: <20250718164119.089692174@kernel.org> Precedence: bulk X-Mailing-List: bpf@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 1fa554e2666d..bd0a33f389d2 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 = !event->attr.exclude_callchain_kernel; - bool user = !event->attr.exclude_callchain_user; + bool user = !event->attr.exclude_callchain_user && + !(current->flags & (PF_KTHREAD | PF_USER_WORKER)); /* 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