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 E41B9C00A5A for ; Wed, 18 Jan 2023 01:44:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229449AbjARBo3 (ORCPT ); Tue, 17 Jan 2023 20:44:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56076 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229863AbjARBoP (ORCPT ); Tue, 17 Jan 2023 20:44:15 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DD6BD51C54; Tue, 17 Jan 2023 17:43:12 -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 11D82615DA; Wed, 18 Jan 2023 01:43:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7CFFC433EF; Wed, 18 Jan 2023 01:43:10 +0000 (UTC) Date: Tue, 17 Jan 2023 20:43:09 -0500 From: Steven Rostedt To: "Masami Hiramatsu (Google)" Cc: linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, Florent Revest , Mark Rutland , Will Deacon Subject: Re: [RFC PATCH 1/9] fprobe: Pass entry_data to handlers Message-ID: <20230117204309.1cd8f20f@gandalf.local.home> In-Reply-To: <166792256330.919356.14776044963704066797.stgit@devnote3> References: <166792255429.919356.14116090269057513181.stgit@devnote3> <166792256330.919356.14776044963704066797.stgit@devnote3> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; 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: linux-trace-kernel@vger.kernel.org On Wed, 9 Nov 2022 00:49:23 +0900 "Masami Hiramatsu (Google)" wrote: > diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c > index e8143e368074..fa25d09c9d57 100644 > --- a/kernel/trace/fprobe.c > +++ b/kernel/trace/fprobe.c > @@ -17,14 +17,16 @@ > struct fprobe_rethook_node { > struct rethook_node node; > unsigned long entry_ip; > + char data[]; > }; > > static void fprobe_handler(unsigned long ip, unsigned long parent_ip, > struct ftrace_ops *ops, struct ftrace_regs *fregs) > { > struct fprobe_rethook_node *fpr; > - struct rethook_node *rh; > + struct rethook_node *rh = NULL; > struct fprobe *fp; > + void *entry_data = NULL; > int bit; > > fp = container_of(ops, struct fprobe, ops); > @@ -37,9 +39,6 @@ static void fprobe_handler(unsigned long ip, unsigned long parent_ip, > return; > } > > - if (fp->entry_handler) > - fp->entry_handler(fp, ip, ftrace_get_regs(fregs)); > - > if (fp->exit_handler) { > rh = rethook_try_get(fp->rethook); > if (!rh) { > @@ -48,9 +47,16 @@ static void fprobe_handler(unsigned long ip, unsigned long parent_ip, > } > fpr = container_of(rh, struct fprobe_rethook_node, node); > fpr->entry_ip = ip; > - rethook_hook(rh, ftrace_get_regs(fregs), true); > + if (fp->entry_data_size) > + entry_data = fpr->data; > } > > + if (fp->entry_handler) > + fp->entry_handler(fp, ip, ftrace_get_regs(fregs), entry_data); > + > + if (rh) > + rethook_hook(rh, ftrace_get_regs(fregs), true); > + > out: > ftrace_test_recursion_unlock(bit); > } > @@ -81,7 +87,8 @@ static void fprobe_exit_handler(struct rethook_node *rh, void *data, > > fpr = container_of(rh, struct fprobe_rethook_node, node); > > - fp->exit_handler(fp, fpr->entry_ip, regs); > + fp->exit_handler(fp, fpr->entry_ip, regs, > + fp->entry_data_size ? (void *)fpr->data : NULL); > } > NOKPROBE_SYMBOL(fprobe_exit_handler); > > @@ -146,7 +153,7 @@ static int fprobe_init_rethook(struct fprobe *fp, int num) > for (i = 0; i < size; i++) { > struct fprobe_rethook_node *node; > > - node = kzalloc(sizeof(*node), GFP_KERNEL); > + node = kzalloc(sizeof(*node) + fp->entry_data_size, GFP_KERNEL); node = kzalloc(struct_size(node, data, fp->entry_data_size), GFP_KERNEL); Should use struct_size() for any tail structure allocations. -- Steve > if (!node) { > rethook_free(fp->rethook); > fp->rethook = NULL; > diff --git a/lib/test_fprobe.c b/lib/test_fprobe.c > index e0381b3ec410..34fa5a5bbda1 100644