From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77051C0015E for ; Thu, 10 Aug 2023 00:39:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230071AbjHJAjT (ORCPT ); Wed, 9 Aug 2023 20:39:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51270 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229470AbjHJAjI (ORCPT ); Wed, 9 Aug 2023 20:39:08 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DD66E26A0; Wed, 9 Aug 2023 17:38:52 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 73E9C64CA9; Thu, 10 Aug 2023 00:38:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2DDA7C433C7; Thu, 10 Aug 2023 00:38:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1691627931; bh=WrUTXC6uZjIJQaROzuUF9MIOrS/vce2evjZsylCt4wc=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=icx7BuejGWgQgdLOejuiVvwevfHp410W6RFZHWf6b76nLjgPpuwce3UJ3nKshFNej D0kuuMcogJ/IR91m2pOGC+D4ILV2jdYk4SX3pNEcDYrBxU0ktSD4p7Ft/ROwAMobOy j1F+duGqMm4TaR0My8lIgRmcaIShJZv9T4zjtsN6OrP776fHTDWlLJFKn8bK9gMTgk b17i9kv5vuYgcxaVdOBQubAqarBTny43Uy6ehQOmWSnqmyKLwHa11gIkzFanmww4xE rEx4iH+RE0Enkh0PbDaZtsS+j1FjKJbqep4xSTcwFt5Sr4bVrX3DOHUSmGmAczfm7q UFbENRY1hm5xg== Date: Thu, 10 Aug 2023 09:38:45 +0900 From: Masami Hiramatsu (Google) To: Florent Revest Cc: Alexei Starovoitov , Steven Rostedt , linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner Subject: Re: [RFC PATCH v2 4/6] tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS Message-Id: <20230810093845.7ebbe1ada897a4afe861e331@kernel.org> In-Reply-To: References: <169139090386.324433.6412259486776991296.stgit@devnote2> <169139095066.324433.15514499924371317690.stgit@devnote2> <20230809234512.e3c39b8fffcc6297262f8fc8@kernel.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org On Wed, 9 Aug 2023 17:38:00 +0200 Florent Revest wrote: > On Wed, Aug 9, 2023 at 4:45 PM Masami Hiramatsu wrote: > > > > --- a/kernel/trace/trace_fprobe.c > > > > +++ b/kernel/trace/trace_fprobe.c > > > > @@ -132,25 +132,30 @@ static int > > > > process_fetch_insn(struct fetch_insn *code, void *rec, void *dest, > > > > void *base) > > > > { > > > > - struct pt_regs *regs = rec; > > > > - unsigned long val; > > > > + struct ftrace_regs *fregs = rec; > > > > + unsigned long val, *stackp; > > > > int ret; > > > > > > > > retry: > > > > /* 1st stage: get value from context */ > > > > switch (code->op) { > > > > case FETCH_OP_STACK: > > > > - val = regs_get_kernel_stack_nth(regs, code->param); > > > > + stackp = (unsigned long *)ftrace_regs_get_stack_pointer(fregs); > > > > + if (((unsigned long)(stackp + code->param) & ~(THREAD_SIZE - 1)) == > > > > + ((unsigned long)stackp & ~(THREAD_SIZE - 1))) > > > > > > Maybe it'd be worth extracting a local > > > "ftrace_regs_get_kernel_stack_nth_addr" helper function and/or > > > "ftrace_regs_within_kernel_stack" ? > > > > Yeah, maybe we can make it a generic inline function in linux/ftrace.h. > > Or even just above this function if there are low chances it would get > used elsewhere :) Thanks, but since regs_get_kernel_stack_nth() is defined in asm/ptrace.h, I think ftrace_regs_get_kernel_stack_nth() is better defined in linux/ftrace.h. :) Thank you! -- Masami Hiramatsu (Google)