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 0C0FCFC1D; Fri, 16 May 2025 14:04:55 +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=1747404296; cv=none; b=L4RV4rD5noqxQ4+Ge8YVa66cjlz8UabsiXGM/xlfGP9QrTKAdHCqziqSEWZDv/ah8mLLQx5iR5UvlPTbOX9uD8OTGc65HBR534yK7T1Vkim+T03lUPEDvCWNjAxZi9TTp0uOVaUjxtktdc9P7T5WGAkMbPC3gDFGqPCrPz53fkA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747404296; c=relaxed/simple; bh=AcX7tJ/ZUkuJv8Tg+tmGlLiFwaFyI1AG9s7LQ2m9uK8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=njcl3vDJH+uHd1YQ0ZiaJN3Kgo4IFPXjWVM6crvlXVeqHM5001hFKcKIym4PcR3Gj2Xu4mubkzWzs9acO+mU4/ggXt47VZ3q/y5G4WFc4XCGzKMcMXMxfjWjff2uv/5F7lbj5wBzbxprMpiznWB+m31LsUXwrfk6nnz/7HAEkrc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=FWXEi9y0; 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="FWXEi9y0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DEE4EC4CEE4; Fri, 16 May 2025 14:04:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1747404295; bh=AcX7tJ/ZUkuJv8Tg+tmGlLiFwaFyI1AG9s7LQ2m9uK8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=FWXEi9y0sujjRRuBmABfYG8aC8Yb7Ogj/u2xJ6sng23hf5pdWO2uNgvuZ7suPU89g VuOGWbFRg0G4wOkLNGFvFjeRM03/+EX2ebf8mpM+ftoXYYW5TWTBNpKt2d1IWXM87n si6S4k12240nPIvNtouc1TuXPp7VzoppyggtYqcCCJ3Mtz/q6UHkkiovr3bA5YwQPw bvsaONlIpfUmZhIt2kfPfx/PST5Mi5+tl9UivVejq4c0RWDco1eOMGWGMEI1Phr482 GSlJDRrPzIxp+85quro+fUgIgRxIDepmx0Xk9fHJjDw8nm2BxRnMiw2v+vLKc4p6Ri AHbivDFiHCJHA== Date: Fri, 16 May 2025 15:04:50 +0100 From: Will Deacon To: Nam Cao Cc: Steven Rostedt , Gabriele Monaco , linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, john.ogness@linutronix.de, Catalin Marinas , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v6 17/22] arm64: mm: Add page fault trace points Message-ID: <20250516140449.GB13612@willie-the-truck> References: <554038c996662282df8a9d0482ef06f8d44fccc5.1745999587.git.namcao@linutronix.de> 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=us-ascii Content-Disposition: inline In-Reply-To: <554038c996662282df8a9d0482ef06f8d44fccc5.1745999587.git.namcao@linutronix.de> User-Agent: Mutt/1.10.1 (2018-07-13) On Wed, Apr 30, 2025 at 01:02:32PM +0200, Nam Cao wrote: > Add page fault trace points, which are useful to implement RV monitor which > watches page faults. > > Signed-off-by: Nam Cao > --- > Cc: Catalin Marinas > Cc: Will Deacon > Cc: linux-arm-kernel@lists.infradead.org > --- > arch/arm64/mm/fault.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c > index ef63651099a9..e3f096b0dffd 100644 > --- a/arch/arm64/mm/fault.c > +++ b/arch/arm64/mm/fault.c > @@ -44,6 +44,9 @@ > #include > #include > > +#define CREATE_TRACE_POINTS > +#include > + > struct fault_info { > int (*fn)(unsigned long far, unsigned long esr, > struct pt_regs *regs); > @@ -559,6 +562,11 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, > if (kprobe_page_fault(regs, esr)) > return 0; > > + if (user_mode(regs)) > + trace_page_fault_user(addr, regs, esr); > + else > + trace_page_fault_kernel(addr, regs, esr); Why is this after kprobe_page_fault()? It's also a shame that the RV monitor can't hook into perf, as we already have a sw event for page faults that you could use instead of adding something new. Will