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 CC09B21322F; Tue, 8 Jul 2025 02:00:50 +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=1751940050; cv=none; b=Oy5vxvNQIcAWlchFpkh4w56xDfQozgjhrliEOjpMN0utZ3Sdu2uVweZFgPfK0B2IbZIleCT4Osb51mfU/aAOr46gu2CXryLYBT1G4C8AnynRuQ9oI+Z5v/FCyRUHXWxv+PbbJzGTs3M6ijSdo5pp5EZQ9cD8fmhQMfNTNnwF/Ys= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751940050; c=relaxed/simple; bh=EDFYhtIoHL2t5VxVx/btjvGxq6ZgeYcUC021YO47Sok=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=KAZ5QKdHgY/etFOLTzg+7yYZHjfFw8cHbXsPPZo8DlbYfs2ArNtYfm5CcsuWCWlo6Rc+CSOaPsVecCFKkNyGcimOdNzZLXaI4S+97zeIV5Q2nIo36Im8kIE28Ar23YynzuAEoE9ETmfpdWFDSkd29QXgBWMCn8sOfGKidDe52F4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RJEQJi3v; 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="RJEQJi3v" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A05F2C4CEE3; Tue, 8 Jul 2025 02:00:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1751940050; bh=EDFYhtIoHL2t5VxVx/btjvGxq6ZgeYcUC021YO47Sok=; h=Date:From:To:Cc:Subject:References:From; b=RJEQJi3vo0kyt8p4l/HveockeAFsAUqmlhZDXUL/wMs7PfsW1R7n9VVm7EkTl5oWV aikAfwPVnah0cSahGNcEbuzy1jzMvjx2+VqrG5T6Fpqjlema0GnL420BXUTYDSUySl 8lOAOQXuBgpXggXpJDWD5YpM1m6OCcSEQ2S+n6AXBtzzCMczF/RtbqBYEQuv9i54iL DZDpBTTcEfj/WbD1A83sKK1+UKPHZ+z1+OIrLm+YBe/C+ssXlYfRZjhGn/tVPDz2+G /ueTs1fauPSu5SZ5wZ3WrV5bmitNHmjsx5cMsLVzARvNzVaL0AsoiueFzRBwj5kyZ3 rbAPd9FECsXoQ== Received: from rostedt by gandalf with local (Exim 4.98.2) (envelope-from ) id 1uYxda-00000000D67-3nc9; Mon, 07 Jul 2025 22:00:50 -0400 Message-ID: <20250708020050.757867061@kernel.org> User-Agent: quilt/0.68 Date: Mon, 07 Jul 2025 22:00:08 -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 , Florian Weimer , Sam James Subject: [PATCH v13 05/11] perf: Skip user unwind if the task is a kernel thread References: <20250708020003.565862284@kernel.org> Precedence: bulk X-Mailing-List: linux-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) --- Changes since v11: https://lore.kernel.org/20250625231622.509379386@goodmis.org - Added test against PF_USER_WORKER as well as PF_KTHREAD 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 cf35dc707ad5..a594bd01d5bc 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