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 2E101C433FE for ; Thu, 2 Dec 2021 10:59:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1357072AbhLBLCz (ORCPT ); Thu, 2 Dec 2021 06:02:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44570 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233830AbhLBLCz (ORCPT ); Thu, 2 Dec 2021 06:02:55 -0500 Received: from mail-ed1-x531.google.com (mail-ed1-x531.google.com [IPv6:2a00:1450:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BB9DBC06174A for ; Thu, 2 Dec 2021 02:59:32 -0800 (PST) Received: by mail-ed1-x531.google.com with SMTP id r11so114266287edd.9 for ; Thu, 02 Dec 2021 02:59:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=PbQpqxxIHdEIFacRsDS+C6vCgFUH8fVOY6dIYyIkuwo=; b=eGQL1V1uebBspwuvp0MrxjtSqAoFr5BrRR2ZtcpwevfUYXhIWcFwnxbSF4hxb2/8ps vo9J/lAMVtY+8mBqgUX4+7NQ02/r3nVu8YSX6Jd4saa/CAt/0V4IEQLixIn04ww1OWAP oD9X2IyliwFvqsjAgK5Tc9O/Mpxtt6mtzjxrfw9epHE6F3LesEEastOeFPB7qm27ha1w ImayZHLMD8fLx1M0SwPbY0bOjbJF9ZrlXBxtNe41Z+YKcegllLs0THNxSZjJC8mgDsuy DGLHVFyh3smukGlJS/FpJfU5yUFeWPMn+6cUtGCVUvtGC9XTLpD5E3ogzFKxolCjUg4z KJaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=PbQpqxxIHdEIFacRsDS+C6vCgFUH8fVOY6dIYyIkuwo=; b=BOxbBGims74nWPld5z4KdxYG2kK8LcDwIeW95gnz5li5ZYlW6WJxe9ZRemEBX0OQoN EhHpX5Q2tpI1jCKbfNusIQZY2CYjbaQISQQt/aTOa4r8+htT/uzZc0yXFih4axXQs3Ni YHirsSDTZt7cf+s9Ab/mcl7P2sarFcpaEfX0/GMC0CsZ7ExfCZlL0rLJmXb/SnvMZTw4 K3MZbKkhOSsBT4jNzTxv2UI+hsjBkwLjx/IKhD+OB8wVzX93qYvRhP6Q/9knJNOCKeoj WIibVULfHNglbDS20cw6acW01KHhq0x6afm9iUG/ghu+ultUajc1obxreULfYqE9qYfL wtMw== X-Gm-Message-State: AOAM532aeVLstGQDOtcic5rnrbgdqd2bfTwFoNUHAcv5FkkoRcY7jPi+ A/HAHL+OqiRnyMI/ALPtsboYAduE78fh5A== X-Google-Smtp-Source: ABdhPJx1m2AjZunRQperjg0EXJZBSnJ650ftduJWrI74oSW0zYTJY417sYcnET2w32Zp0LItjIooSg== X-Received: by 2002:a05:6402:26d4:: with SMTP id x20mr16902897edd.119.1638442771250; Thu, 02 Dec 2021 02:59:31 -0800 (PST) Received: from oberon.zico.biz.zico.biz ([83.222.187.186]) by smtp.gmail.com with ESMTPSA id e19sm1852930edu.47.2021.12.02.02.59.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Dec 2021 02:59:30 -0800 (PST) From: "Tzvetomir Stoyanov (VMware)" To: rostedt@goodmis.org Cc: linux-trace-devel@vger.kernel.org Subject: [PATCH v2 2/4] libtracefs: New API for getting dynamic event Date: Thu, 2 Dec 2021 12:59:24 +0200 Message-Id: <20211202105926.32581-3-tz.stoyanov@gmail.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211202105926.32581-1-tz.stoyanov@gmail.com> References: <20211202105926.32581-1-tz.stoyanov@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org A new API is proposed, to get tep event describing given dynamic event: tracefs_dynevent_get_event() The API detects any newly created or removed dynamic events. Signed-off-by: Tzvetomir Stoyanov (VMware) --- Documentation/libtracefs-dynevents.txt | 13 ++++++++-- include/tracefs.h | 2 ++ src/tracefs-dynevents.c | 33 ++++++++++++++++++++++++++ 3 files changed, 46 insertions(+), 2 deletions(-) diff --git a/Documentation/libtracefs-dynevents.txt b/Documentation/libtracefs-dynevents.txt index a374651..bec31f1 100644 --- a/Documentation/libtracefs-dynevents.txt +++ b/Documentation/libtracefs-dynevents.txt @@ -4,8 +4,8 @@ libtracefs(3) NAME ---- tracefs_dynevent_create, tracefs_dynevent_destroy, tracefs_dynevent_destroy_all, -tracefs_dynevent_free, tracefs_dynevent_list_free, tracefs_dynevent_get_all, tracefs_dynevent_info - -Create, destroy, free and get dynamic events. +tracefs_dynevent_free, tracefs_dynevent_list_free, tracefs_dynevent_get_all, tracefs_dynevent_info, +tracefs_dynevent_get_event - Create, destroy, free and get dynamic events. SYNOPSIS -------- @@ -23,6 +23,7 @@ void *tracefs_dynevent_list_free*(struct tracefs_dynevent pass:[*]pass:[*]_event struct tracefs_dynevent pass:[*]*tracefs_dynevent_get*(enum tracefs_dynevent_type _type_, const char pass:[*]_system_, const char pass:[*]_event_); struct tracefs_dynevent pass:[*]pass:[*]*tracefs_dynevent_get_all*(unsigned int _types_, const char pass:[*]_system_); enum tracefs_dynevent_type *tracefs_dynevent_info*(struct tracefs_dynevent pass:[*]_dynevent_, char pass:[*]pass:[*]_system_, char pass:[*]pass:[*]_event_, char pass:[*]pass:[*]_prefix_, char pass:[*]pass:[*]_addr_, char pass:[*]pass:[*]_format_); +struct tep_event pass:[*]*tracefs_dynevent_get_event*(struct tep_handle pass:[*]_tep_, struct tracefs_dynevent pass:[*]_dynevent_); -- DESCRIPTION @@ -68,6 +69,10 @@ if relevant for this event type. If _format_ is non NULL, it will hold the forma dynamic event. Note, that the content in _group_, _event_, _prefix_, _addr_, and _format_ must be freed with free(3) if they are set. +The *tracefs_dynevent_get_event*() function returns a tep event, describing the given dynamic event. +The API detects any newly created or removed dynamic events. The returned pointer to tep event is +controlled by @tep and must not be freed. + RETURN VALUE ------------ @@ -88,6 +93,10 @@ in case of an error or in case there are no events in the system. That array mus on error. If _system_, _event_, _prefix_, _addr_, or _format_ are non NULL, they will contain allocated strings that must be freed by free(3). +The *tracefs_dynevent_get_event*() function returns a pointer to a tep event or NULL in case of an +error or if the requested dynamic event is missing. The returned pointer to tep event is controlled +by @tep and must not be freed. + ERRORS ------ The following errors are for all the above calls: diff --git a/include/tracefs.h b/include/tracefs.h index c9ebaa6..383974b 100644 --- a/include/tracefs.h +++ b/include/tracefs.h @@ -262,6 +262,8 @@ tracefs_dynevent_get(enum tracefs_dynevent_type type, const char *system, const enum tracefs_dynevent_type tracefs_dynevent_info(struct tracefs_dynevent *dynevent, char **system, char **event, char **prefix, char **addr, char **format); +struct tep_event * +tracefs_dynevent_get_event(struct tep_handle *tep, struct tracefs_dynevent *dynevent); struct tracefs_dynevent * tracefs_eprobe_alloc(const char *system, const char *event, diff --git a/src/tracefs-dynevents.c b/src/tracefs-dynevents.c index ea07d13..d089d02 100644 --- a/src/tracefs-dynevents.c +++ b/src/tracefs-dynevents.c @@ -752,3 +752,36 @@ error: return TRACEFS_DYNEVENT_UNKNOWN; } + +/** + * tracefs_dynevent_get_event - return tep event representing the given dynamic event + * @tep: a handle to the trace event parser context that holds the events + * @dynevent: a dynamic event context, describing given dynamic event. + * + * Returns a pointer to a tep event describing the given dynamic event. The pointer + * is managed by the @tep handle and must not be freed. In case of an error, or in case + * the requested dynamic event is missing in the @tep handler - NULL is returned. + */ +struct tep_event * +tracefs_dynevent_get_event(struct tep_handle *tep, struct tracefs_dynevent *dynevent) +{ + struct tep_event *event; + + if (!tep || !dynevent || !dynevent->event) + return NULL; + + /* Check if event exists in the system */ + if (!tracefs_event_file_exists(NULL, dynevent->system, dynevent->event, "format")) + return NULL; + + /* If the dynamic event is already loaded in the tep, return it */ + event = tep_find_event_by_name(tep, dynevent->system, dynevent->event); + if (event) + return event; + + /* Try to load any new events from the given system */ + if (trace_rescan_events(tep, NULL, dynevent->system)) + return NULL; + + return tep_find_event_by_name(tep, dynevent->system, dynevent->event); +} -- 2.33.1