From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755078AbbAWB6k (ORCPT ); Thu, 22 Jan 2015 20:58:40 -0500 Received: from szxga01-in.huawei.com ([119.145.14.64]:32484 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752908AbbAWB6j (ORCPT ); Thu, 22 Jan 2015 20:58:39 -0500 Message-ID: <54C1AAA1.4000300@huawei.com> Date: Fri, 23 Jan 2015 09:57:53 +0800 From: Wang Nan User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.0.1 MIME-Version: 1.0 To: Jiri Olsa , CC: , , , Subject: Re: [PATCH RFC 2/2] perf: convert: fix duplicate field names and avoid reserved keywords. References: <1421904958-24106-1-git-send-email-wangnan0@huawei.com> <1421905003-24242-1-git-send-email-wangnan0@huawei.com> <20150122132734.GB2473@krava.brq.redhat.com> In-Reply-To: <20150122132734.GB2473@krava.brq.redhat.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.111.69.129] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2015/1/22 21:27, Jiri Olsa wrote: > On Thu, Jan 22, 2015 at 01:36:43PM +0800, Wang Nan wrote: >> (If Steven Rostedt accept the previous patch which introduce a priv >> field to 'struct format_field', we can use a relative simple method >> for name conversion. If not , perf must track name conversion by >> itself.) >> >> Some parameters of syscall tracepoints named as 'nr', 'event', etc. >> When dealing with them, perf convert to ctf meets some problem: >> >> 1. If a parameter with name 'nr', it will duplicate syscall's >> common field 'nr'. One such syscall is io_submit(). >> >> 2. If a parameter with name 'event', it is denied to be inserted >> because 'event' is a babeltrace keywork. One such syscall is >> epoll_ctl. >> >> This patch appends '_dupl_X' suffix to avoid problem 1, prepend a '_' >> prefix to avoid problem 2. > > I've got compilation error: > > util/data-convert-bt.c: In function ‘event_class_add_field’: > util/data-convert-bt.c:629:2: error: suggest parentheses around assignment used as truth value [-Werror=parentheses] > while (t = bt_ctf_event_class_get_field_by_name(event_class, name)) { > > what's your gcc version? mine's caught that.. > I also curious why you got so many Werror problems I'm not ever seen, until I found a '-w' in my gcc options, which is introduced by your commit 47810c1d429bc690e1f5e9467697538921962171: perf data: Disable Werror convert object. I'll revert that commit in my tree. > [jolsa@krava perf]$ gcc --version > gcc (GCC) 4.8.3 20140911 (Red Hat 4.8.3-7) > > SNIP > >> >> +/* If dup < 0, add a prefix. Else, add _dupl_X suffix. */ >> +static char *change_name(char *name, char *orig_name, int dup) >> +{ >> + char *new_name = NULL; >> + size_t len; >> + >> + if (!name) >> + name = orig_name; >> + >> + if (dup >= 10) >> + goto out; >> + >> + if (dup < 0) >> + len = strlen(name) + sizeof("_"); >> + else >> + len = strlen(orig_name) + sizeof("_dupl_X"); > > if we allow for _dupl_10, should we use 'sizeof("_dupl_x")' ^^^ in here? > >> + >> + new_name = malloc(len); >> + if (!new_name) >> + goto out; >> + >> + if (dup < 0) >> + snprintf(new_name, len, "_%s", name); >> + else >> + snprintf(new_name, len, "%s_dupl_%d", orig_name, dup); >> + >> +out: >> + if (name != orig_name) >> + free(name); >> + return new_name; > > SNIP > >> + >> + name = field->name; >> + while (t = bt_ctf_event_class_get_field_by_name(event_class, name)) { >> + bt_ctf_field_type_put(t); >> + name = change_name(name, field->name, dup++); >> + if (!name) { >> + pr_err("Failed to create dup name for '%s'\n", field->name); >> + return -1; >> + } >> + } >> + >> + ret = bt_ctf_event_class_add_field(event_class, type, name); >> + >> + /* if failed, we may hit a keywork. try again with a '_' prefix */ >> + if (ret) { >> + name = change_name(name, field->name, -1); >> + if (!name) { >> + pr_err("Failed to alloc name for '_%s'\n", field->name); >> + return -1; >> + } >> + ret = bt_ctf_event_class_add_field(event_class, type, name); > > so there's no other way on checking up with the blacklist right? > AFAIK there's no official method to check blacklist right now. Utilizing existing functions to check blacklist is possible. For example, we can create a clock using bt_ctf_clock_create() with the checked name and then free it. However, it is hacky and I think you won't like it. I believe my solution should be acceptable before babeltrace export its validate_identifier() function to users. Jérémie Galarneau, do you have better idea on it? Thanks. > thanks, > jirka >