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 X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3F815C433FF for ; Tue, 30 Jul 2019 00:03:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 05F29206BA for ; Tue, 30 Jul 2019 00:03:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="rw3D+SzU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730213AbfG3AD3 (ORCPT ); Mon, 29 Jul 2019 20:03:29 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:54368 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730149AbfG3ADV (ORCPT ); Mon, 29 Jul 2019 20:03:21 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x6TNxKAh046010; Tue, 30 Jul 2019 00:02:52 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2018-07-02; bh=Kn8U6rIU5msAsOTmODkxifyAYd/RbQuaiP5BL0MbKLw=; b=rw3D+SzUyjG2YJppShG2lJx5VB768B/eyqnwwTkzl2i6XvB0DDew/8CDCRKUHpbiEsqn exDmwu6pT5tlApdnTeHcYd6xPd6yyhWuLAlBQ6iX3LopHbXpDLxGJP0TRz7RIXbTg8CP ULe7vXFOyjdvog0cayiFd/VyCggBNsh3ocKGfTOfkj+WacZZAUAoETxLzIfrDzf0ryb/ z6JeICGX0pmTZnbvL1MUdlFoxtt+4Y+Ii89AUCEzu0HcYFHIZaSabIGGb3Zl1zpn2/aF STRSBNnuUm4vsl2+9YXlg4U2plzMjKTOn0bAJxEBS2s4v7c5pbCq0ZjZ0L5KXFPQEi58 Kg== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by aserp2120.oracle.com with ESMTP id 2u0ejparbp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 30 Jul 2019 00:02:52 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x6TNvh85019805; Tue, 30 Jul 2019 00:02:52 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserp3020.oracle.com with ESMTP id 2u0ee4kv4h-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 30 Jul 2019 00:02:52 +0000 Received: from abhmp0012.oracle.com (abhmp0012.oracle.com [141.146.116.18]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x6U02pS5012435; Tue, 30 Jul 2019 00:02:51 GMT Received: from ca-common-hq.us.oracle.com (/10.211.9.209) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 29 Jul 2019 17:02:50 -0700 From: Divya Indi To: linux-kernel@vger.kernel.org, Steven Rostedt Cc: Divya Indi , Joe Jin , Aruna Ramakrishna , Srinivas Eeda Subject: [PATCH 6/7] tracing: New functions for kernel access to Ftrace instances Date: Mon, 29 Jul 2019 17:02:33 -0700 Message-Id: <1564444954-28685-7-git-send-email-divya.indi@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1564444954-28685-1-git-send-email-divya.indi@oracle.com> References: <1564444954-28685-1-git-send-email-divya.indi@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9333 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1907290261 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9333 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1907290261 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Adding 2 new functions - 1) trace_array_lookup : Look up and return a trace array, given its name. 2) trace_array_set_clr_event : Enable/disable event recording to the given trace array. NOTE: trace_array_lookup returns a trace array and also increments the reference counter associated with the returned trace array. Make sure to call trace_array_put() once the use is done so that the instance can be removed at a later time. Example use: tr = trace_array_lookup("foo-bar"); if (!tr) tr = trace_array_create("foo-bar"); // Log to tr // Enable/disable events to tr trace_array_set_clr_event(tr, _THIS_IP,"system","event",1); // Done using tr trace_array_put(tr); .. Signed-off-by: Divya Indi Reviewed-By: Aruna Ramakrishna --- include/linux/trace.h | 2 ++ include/linux/trace_events.h | 2 ++ kernel/trace/trace.c | 28 ++++++++++++++++++++++++++++ kernel/trace/trace_events.c | 22 ++++++++++++++++++++++ 4 files changed, 54 insertions(+) diff --git a/include/linux/trace.h b/include/linux/trace.h index 2c782d5..05164bb 100644 --- a/include/linux/trace.h +++ b/include/linux/trace.h @@ -32,6 +32,8 @@ int trace_array_printk(struct trace_array *tr, unsigned long ip, struct trace_array *trace_array_create(const char *name); int trace_array_destroy(struct trace_array *tr); void trace_array_put(struct trace_array *tr); +struct trace_array *trace_array_lookup(const char *name); + #endif /* CONFIG_TRACING */ #endif /* _LINUX_TRACE_H */ diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 0f874fb..6da3600 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -540,6 +540,8 @@ extern int trace_define_field(struct trace_event_call *call, const char *type, #define is_signed_type(type) (((type)(-1)) < (type)1) int trace_set_clr_event(const char *system, const char *event, int set); +int trace_array_set_clr_event(struct trace_array *tr, const char *system, + const char *event, int set); int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set); /* diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 130579b..fcf42bb 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -8516,6 +8516,34 @@ static int instance_rmdir(const char *name) return ret; } +/** + * trace_array_lookup - Lookup the trace array, given its name. + * @name: The name of the trace array to be looked up. + * + * Lookup and return the trace array associated with @name. + * + * NOTE: The reference counter associated with the returned trace array is + * incremented to ensure it is not freed when in use. Make sure to call + * "trace_array_put" for this trace array when its use is done. + */ +struct trace_array *trace_array_lookup(const char *name) +{ + struct trace_array *tr; + + mutex_lock(&trace_types_lock); + + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (tr->name && strcmp(tr->name, name) == 0) { + tr->ref++; + mutex_unlock(&trace_types_lock); + return tr; + } + } + mutex_unlock(&trace_types_lock); + return NULL; +} +EXPORT_SYMBOL_GPL(trace_array_lookup); + static __init void create_trace_instances(struct dentry *d_tracer) { trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 99eb5f8..9ee6b52 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -859,6 +859,28 @@ int trace_set_clr_event(const char *system, const char *event, int set) } EXPORT_SYMBOL_GPL(trace_set_clr_event); +/** + * trace_array_set_clr_event - enable or disable an event for a trace array + * @system: system name to match (NULL for any system) + * @event: event name to match (NULL for all events, within system) + * @set: 1 to enable, 0 to disable + * + * This is a way for other parts of the kernel to enable or disable + * event recording to instances. + * + * Returns 0 on success, -EINVAL if the parameters do not match any + * registered events. + */ +int trace_array_set_clr_event(struct trace_array *tr, const char *system, + const char *event, int set) +{ + if (!tr) + return -ENOENT; + + return __ftrace_set_clr_event(tr, NULL, system, event, set); +} +EXPORT_SYMBOL_GPL(trace_array_set_clr_event); + /* 128 should be much more than enough */ #define EVENT_BUF_SIZE 127 -- 1.8.3.1