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 EB293C433EF for ; Mon, 7 Mar 2022 14:00:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240396AbiCGOB3 (ORCPT ); Mon, 7 Mar 2022 09:01:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53726 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239786AbiCGOB2 (ORCPT ); Mon, 7 Mar 2022 09:01:28 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA03889333; Mon, 7 Mar 2022 06:00:34 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 45E7F61266; Mon, 7 Mar 2022 14:00:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 54DF5C340EB; Mon, 7 Mar 2022 14:00:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646661633; bh=AUTZ4SHzz2itvOQ5SUm88SHoX24HvJUW+0NaQzv8J3k=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=F2td//5fwB39fMMh4fLb1tfGTG7iJWRLyOteTNLVh3RSr7ZDvo6TI5EoHtEmkldr3 JHettZzepZj6pizKJFWpNJOPkrGYfw0hjj3nO54kOmGilLmflhHz/au6guRoCLiAQQ xArwZmCN2pbLODGTDEdML7aYksfF62X6/rGLeSkwVGAsxhWkB9WOYHALLVuf7xhik/ T5c5EJY/3T3/j0OOwETzv0rktoa19OAdGNW7dC2pGwIr4m9qQltiOWS8z8i0lsO1vh m0l5yJbkSfCHreDcZgmA7uz83N7gK2UvdAUiqHTfwMuSFL6tqoG2nJ0DYYqS2+hddc 4rmFvAw3Haetw== Date: Mon, 7 Mar 2022 23:00:27 +0900 From: Masami Hiramatsu To: Jiri Olsa Cc: Jiri Olsa , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , netdev@vger.kernel.org, bpf@vger.kernel.org, lkml , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Steven Rostedt , "Naveen N . Rao" , Anil S Keshavamurthy , "David S . Miller" Subject: Re: [PATCH v9 02/11] fprobe: Add ftrace based probe APIs Message-Id: <20220307230027.679cca95a201b094e700716d@kernel.org> In-Reply-To: References: <164655933970.1674510.3809060481512713846.stgit@devnote2> <164655936328.1674510.15506582463881824113.stgit@devnote2> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Mon, 7 Mar 2022 13:55:31 +0100 Jiri Olsa wrote: > On Sun, Mar 06, 2022 at 06:36:03PM +0900, Masami Hiramatsu wrote: > > SNIP > > > +} > > +NOKPROBE_SYMBOL(fprobe_handler); > > + > > +/* Convert ftrace location address from symbols */ > > +static unsigned long *get_ftrace_locations(const char **syms, int num) > > +{ > > + unsigned long addr, size; > > + unsigned long *addrs; > > + int i; > > + > > + /* Convert symbols to symbol address */ > > + addrs = kcalloc(num, sizeof(*addrs), GFP_KERNEL); > > + if (!addrs) > > + return ERR_PTR(-ENOMEM); > > + > > + for (i = 0; i < num; i++) { > > + addrs[i] = kallsyms_lookup_name(syms[i]); > > + if (!addrs[i]) /* Maybe wrong symbol */ > > + goto error; > > + } > > + > > + /* Convert symbol address to ftrace location. */ > > + for (i = 0; i < num; i++) { > > + if (!kallsyms_lookup_size_offset(addrs[i], &size, NULL) || !size) > > + goto error; > > + addr = ftrace_location_range(addrs[i], addrs[i] + size - 1); > > + if (!addr) /* No dynamic ftrace there. */ > > + goto error; > > + addrs[i] = addr; > > + } > > why not one just single loop ? Indeed :-D Thanks! > > jirka > > > > + > > + return addrs; > > + > > +error: > > + kfree(addrs); > > + > > + return ERR_PTR(-ENOENT); > > +} > > + > > +static void fprobe_init(struct fprobe *fp) > > +{ > > + fp->nmissed = 0; > > + fp->ops.func = fprobe_handler; > > + fp->ops.flags |= FTRACE_OPS_FL_SAVE_REGS; > > +} > > SNIP -- Masami Hiramatsu