From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout.efficios.com (smtpout.efficios.com [167.114.26.122]) (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 A7A691AED46; Thu, 20 Jun 2024 15:04:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=167.114.26.122 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718895884; cv=none; b=U4c22u5BTpQdLDeZhyFnmXh8MntIpKJUBwasYirZ/Eu8bcFmhcNw2ZXmkJQf98jUtJmvo7cloH+iscYf4CeYF1IlYu01mcV9dm/KecHyTbkkIbseb/U9Z6TanCh6XjnPlclXeM1fqHbo62p/iPP0Mc7YQ2pkrYyRaZ8nx16gtpc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718895884; c=relaxed/simple; bh=LUPtel0ShUHpNwxjNiaG47yDGOxRzD0GMUdRYFQCXtU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=m5ctFeBgeEG3x1UpKB+DJAGt9Ems+QmHqoigi11KfXLM3HsEmTMJbz0cI32Rp9Tge9iO/BHXwFA1xs8go0rYiMgahEa50R/NHEKOaFqhSJZ1Y+e4RmGf2FIm4cRLcru1MTs2XmLsL18tVQKQH2ftC2oIE6FJNg6L31qUxoVykWY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com; spf=pass smtp.mailfrom=efficios.com; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b=iVdThC4w; arc=none smtp.client-ip=167.114.26.122 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=efficios.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b="iVdThC4w" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=efficios.com; s=smtpout1; t=1718895881; bh=LUPtel0ShUHpNwxjNiaG47yDGOxRzD0GMUdRYFQCXtU=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=iVdThC4wKi9ls35EEToxYZS7xJGS9/gUiZiqJsLLCHZAbmtGnp7ReJoJp2ASlU4lo k7dcMMHap+cbUx/DdVTYtMzYTZMLRSWqaHYu73vDv+o5N+t36F1qnHdBEjJyBIXKQb sQfitlGyv5zoxy/MiozmN/i+r8ug1TeFFKBGZaABWRl5lDKwc3L1ntM1Ur1I6X3FAR RezQUcGvSmYAaVjxgVmkBnkjzfwz8NrColwp7liP0fX58eTPV2XBPeaHRU9rBgi1Ru EkfTbZBIuejzjnI+2lm/09EGe6Ayep92bzmHRwl8j24MCHuJv6RaJoPvTcGdktMhSX qjNyr5LKA4PIQ== Received: from [172.16.0.134] (192-222-143-198.qc.cable.ebox.net [192.222.143.198]) by smtpout.efficios.com (Postfix) with ESMTPSA id 4W4kL132Xmz16rR; Thu, 20 Jun 2024 11:04:41 -0400 (EDT) Message-ID: <2dca3126-5bbd-4d86-a888-b532174ae6f1@efficios.com> Date: Thu, 20 Jun 2024 11:05:42 -0400 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 5/5] tracing: convert sys_enter/exit to faultable tracepoints To: Peter Zijlstra Cc: Steven Rostedt , Masami Hiramatsu , linux-kernel@vger.kernel.org, Michael Jeanson , Alexei Starovoitov , Yonghong Song , "Paul E . McKenney" , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , bpf@vger.kernel.org, Joel Fernandes References: <20231120205418.334172-1-mathieu.desnoyers@efficios.com> <20231120205418.334172-6-mathieu.desnoyers@efficios.com> <20231120214657.GB8262@noisy.programming.kicks-ass.net> From: Mathieu Desnoyers Content-Language: en-US In-Reply-To: <20231120214657.GB8262@noisy.programming.kicks-ass.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2023-11-20 16:46, Peter Zijlstra wrote: > On Mon, Nov 20, 2023 at 03:54:18PM -0500, Mathieu Desnoyers wrote: > >> diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c >> index de753403cdaf..718a0723a0bc 100644 >> --- a/kernel/trace/trace_syscalls.c >> +++ b/kernel/trace/trace_syscalls.c >> @@ -299,27 +299,33 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) >> int syscall_nr; >> int size; >> >> + /* >> + * Probe called with preemption enabled (may_fault), but ring buffer and >> + * per-cpu data require preemption to be disabled. >> + */ >> + preempt_disable_notrace(); > > guard(preempt_notrace)(); > > and ditch all the goto crap. [ more guard stuff ] Sure, will do, thanks! Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com