From patchwork Tue Nov 16 00:50:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Beau Belgrave X-Patchwork-Id: 12620979 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 51C33C433EF for ; Tue, 16 Nov 2021 00:53:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3DA5461B48 for ; Tue, 16 Nov 2021 00:53:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245727AbhKPA4Q (ORCPT ); Mon, 15 Nov 2021 19:56:16 -0500 Received: from linux.microsoft.com ([13.77.154.182]:50006 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358581AbhKPAxw (ORCPT ); Mon, 15 Nov 2021 19:53:52 -0500 Received: from localhost.localdomain (c-73-140-2-214.hsd1.wa.comcast.net [73.140.2.214]) by linux.microsoft.com (Postfix) with ESMTPSA id 77E1C20C6358; Mon, 15 Nov 2021 16:50:52 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 77E1C20C6358 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1637023852; bh=B3Og+dw16JR4kCXlIl3hifpTob62x/9Z/JVvYMJ4OAg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eFrBV2u1IC5qKUI6R7Q+XM3HTxH7Rjxq7IJK+Gpjq0/CHdTQOMuvEGfMmEsH7YXPU gLQxFJVIQG0R0O/3NK64zwmcpFA9+3tT8o1tq5l3uAGrSkz5Wy+rqxMiZFTq/1bpQH pqmHsHaFUubzlUlT3j2tM0Dg/rx3BtjZIqG+Tt7Q= From: Beau Belgrave To: rostedt@goodmis.org, mhiramat@kernel.org Cc: linux-trace-devel@vger.kernel.org, linux-kernel@vger.kernel.org, beaub@linux.microsoft.com Subject: [PATCH v5 04/12] user_events: Handle matching arguments from dyn_events Date: Mon, 15 Nov 2021 16:50:39 -0800 Message-Id: <20211116005047.1808-5-beaub@linux.microsoft.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211116005047.1808-1-beaub@linux.microsoft.com> References: <20211116005047.1808-1-beaub@linux.microsoft.com> Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org Ensures that when dynamic events requests a match with arguments that they match what is in the user_event. Signed-off-by: Beau Belgrave --- kernel/trace/trace_events_user.c | 77 +++++++++++++++++++++++++++++++- 1 file changed, 76 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace_events_user.c b/kernel/trace/trace_events_user.c index 6f4be9dd197e..8415aaf8e3b1 100644 --- a/kernel/trace/trace_events_user.c +++ b/kernel/trace/trace_events_user.c @@ -39,6 +39,7 @@ #define MAX_EVENT_DESC 512 #define EVENT_NAME(user_event) ((user_event)->tracepoint.name) #define MAX_FIELD_ARRAY_SIZE (2 * PAGE_SIZE) +#define MAX_FIELD_ARG_NAME 256 static char *register_page_data; @@ -679,13 +680,87 @@ static int user_event_free(struct dyn_event *ev) return destroy_user_event(user); } +static bool user_field_match(struct ftrace_event_field *field, int argc, + const char **argv, int *iout) +{ + char *field_name, *arg_name; + int len, pos, i = *iout; + bool colon = false, match = false; + + if (i >= argc) + return false; + + len = MAX_FIELD_ARG_NAME; + field_name = kmalloc(len, GFP_KERNEL); + arg_name = kmalloc(len, GFP_KERNEL); + + if (!arg_name || !field_name) + goto out; + + pos = 0; + + for (; i < argc; ++i) { + if (i != *iout) + pos += snprintf(arg_name + pos, len - pos, " "); + + pos += snprintf(arg_name + pos, len - pos, argv[i]); + + if (strchr(argv[i], ';')) { + ++i; + colon = true; + break; + } + } + + pos = 0; + + pos += snprintf(field_name + pos, len - pos, field->type); + pos += snprintf(field_name + pos, len - pos, " "); + pos += snprintf(field_name + pos, len - pos, field->name); + + if (colon) + pos += snprintf(field_name + pos, len - pos, ";"); + + *iout = i; + + match = strcmp(arg_name, field_name) == 0; +out: + kfree(arg_name); + kfree(field_name); + + return match; +} + +static bool user_fields_match(struct user_event *user, int argc, + const char **argv) +{ + struct ftrace_event_field *field, *next; + struct list_head *head = &user->fields; + int i = 0; + + list_for_each_entry_safe_reverse(field, next, head, link) + if (!user_field_match(field, argc, argv, &i)) + return false; + + if (i != argc) + return false; + + return true; +} + static bool user_event_match(const char *system, const char *event, int argc, const char **argv, struct dyn_event *ev) { struct user_event *user = container_of(ev, struct user_event, devent); + bool match; - return strcmp(EVENT_NAME(user), event) == 0 && + match = strcmp(EVENT_NAME(user), event) == 0 && (!system || strcmp(system, USER_EVENTS_SYSTEM) == 0); + + if (match && argc > 0) + match = user_fields_match(user, argc, argv); + + return match; } static struct dyn_event_operations user_event_dops = {