From patchwork Tue Jan 18 20:43:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Beau Belgrave X-Patchwork-Id: 12716890 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 A64D9C4321E for ; Tue, 18 Jan 2022 20:43:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349296AbiARUne (ORCPT ); Tue, 18 Jan 2022 15:43:34 -0500 Received: from linux.microsoft.com ([13.77.154.182]:43816 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345684AbiARUnb (ORCPT ); Tue, 18 Jan 2022 15:43:31 -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 4872D20B927B; Tue, 18 Jan 2022 12:43:31 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 4872D20B927B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1642538611; bh=q5KI/D692VhGMWb6PRmt3MwCIwpIi9OrMF74O2H645c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IRykAIFChjWuDMceRtxtiQ+gK8qcuDShetO4Ungy/DxtCIR8KaSr/9GIfARjnFjPq RWKqLu8ugu7WFofsxlkkpqrgtS7QCBWK+2rgdKSmc4SkXAQKps8UInOobkmPzIjG6t HkaMo7H011aEoBGkMI9UtSiqxnwPk4LvfdzI9Xpo= 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 v10 03/12] user_events: Handle matching arguments from dyn_events Date: Tue, 18 Jan 2022 12:43:17 -0800 Message-Id: <20220118204326.2169-4-beaub@linux.microsoft.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220118204326.2169-1-beaub@linux.microsoft.com> References: <20220118204326.2169-1-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 ddc5c3cf1bf8..a6794cb1f586 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 1024 +#define MAX_FIELD_ARG_NAME 256 static char *register_page_data; @@ -700,13 +701,87 @@ 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 = {