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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,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 F28AFC1B0E3 for ; Fri, 28 Sep 2018 17:00:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4840620657 for ; Fri, 28 Sep 2018 16:49:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="oPuu/wEv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4840620657 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=fb.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729424AbeI1XOC (ORCPT ); Fri, 28 Sep 2018 19:14:02 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:60210 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726121AbeI1XOB (ORCPT ); Fri, 28 Sep 2018 19:14:01 -0400 Received: from pps.filterd (m0044012.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w8SGeaQN026292 for ; Fri, 28 Sep 2018 09:49:24 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : mime-version : content-type; s=facebook; bh=dkM9JHm7fAniAfb3aa1Kn8b5mX3wW71h8uGQBXR/G9I=; b=oPuu/wEvZyuDQOB7DT7cJJGqpeGosOEHnADQRy156n2PBWIZ+1ZUusacqgsCJymEOEo5 NhQqRoOAkS+Pa+ONfOmxR6oqfqn4ogQ6CwRzvBwpHI7RUZWUxyHB5td3yhJ962dB4p64 h+9hzx3urARXgJV2YuMS7ZUzeQK9Yc/gWkU= Received: from mail.thefacebook.com ([199.201.64.23]) by mx0a-00082601.pphosted.com with ESMTP id 2msn3b0pxw-15 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Fri, 28 Sep 2018 09:49:24 -0700 Received: from mx-out.facebook.com (192.168.52.123) by mail.thefacebook.com (192.168.16.21) with Microsoft SMTP Server (TLS) id 14.3.319.2; Fri, 28 Sep 2018 09:49:22 -0700 Received: by devbig006.ftw2.facebook.com (Postfix, from userid 4523) id 9299662E12DE; Fri, 28 Sep 2018 09:49:15 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Song Liu Smtp-Origin-Hostname: devbig006.ftw2.facebook.com To: CC: , Song Liu , Masami Hiramatsu , Oleg Nesterov , Srikar Dronamraju , "Naveen N . Rao" , Steven Rostedt , Peter Zijlstra Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH v2] trace_uprobe: support reference counter in fd-based uprobe Date: Fri, 28 Sep 2018 09:49:01 -0700 Message-ID: <20180928164901.19782-1-songliubraving@fb.com> X-Mailer: git-send-email 2.17.1 X-FB-Internal: Safe MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-09-28_07:,, signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Changes v1 -> v2: Fix PMU_FORMAT_ATTR as Peter suggested This patch enables uprobes with reference counter in fd-based uprobe. Highest 32 bits of perf_event_attr.config is used to stored offset of the reference count (semaphore). Format information in /sys/bus/event_source/devices/uprobe/format/ is updated to reflect this new feature. Signed-off-by: Song Liu Reviewed-and-tested-by: Ravi Bangoria Cc: Masami Hiramatsu Cc: Oleg Nesterov Cc: Srikar Dronamraju Cc: Naveen N. Rao Cc: Steven Rostedt (VMware) Cc: Peter Zijlstra --- include/linux/trace_events.h | 3 +- kernel/events/core.c | 49 ++++++++++++++++++++++++++------- kernel/trace/trace_event_perf.c | 7 +++-- kernel/trace/trace_probe.h | 3 +- kernel/trace/trace_uprobe.c | 4 ++- 5 files changed, 50 insertions(+), 16 deletions(-) diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 78a010e19ed4..4130a5497d40 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -575,7 +575,8 @@ extern int bpf_get_kprobe_info(const struct perf_event *event, bool perf_type_tracepoint); #endif #ifdef CONFIG_UPROBE_EVENTS -extern int perf_uprobe_init(struct perf_event *event, bool is_retprobe); +extern int perf_uprobe_init(struct perf_event *event, + unsigned long ref_ctr_offset, bool is_retprobe); extern void perf_uprobe_destroy(struct perf_event *event); extern int bpf_get_uprobe_info(const struct perf_event *event, u32 *fd_type, const char **filename, diff --git a/kernel/events/core.c b/kernel/events/core.c index c80549bf82c6..65b30773af3e 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8368,30 +8368,39 @@ static struct pmu perf_tracepoint = { * * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe * if not set, create kprobe/uprobe + * + * The following values specify a reference counter (or semaphore in the + * terminology of tools like dtrace, systemtap, etc.) Userspace Statically + * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. + * + * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset + * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left */ enum perf_probe_config { PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ + PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, + PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, }; PMU_FORMAT_ATTR(retprobe, "config:0"); +#endif -static struct attribute *probe_attrs[] = { +#ifdef CONFIG_KPROBE_EVENTS +static struct attribute *kprobe_attrs[] = { &format_attr_retprobe.attr, NULL, }; -static struct attribute_group probe_format_group = { +static struct attribute_group kprobe_format_group = { .name = "format", - .attrs = probe_attrs, + .attrs = kprobe_attrs, }; -static const struct attribute_group *probe_attr_groups[] = { - &probe_format_group, +static const struct attribute_group *kprobe_attr_groups[] = { + &kprobe_format_group, NULL, }; -#endif -#ifdef CONFIG_KPROBE_EVENTS static int perf_kprobe_event_init(struct perf_event *event); static struct pmu perf_kprobe = { .task_ctx_nr = perf_sw_context, @@ -8401,7 +8410,7 @@ static struct pmu perf_kprobe = { .start = perf_swevent_start, .stop = perf_swevent_stop, .read = perf_swevent_read, - .attr_groups = probe_attr_groups, + .attr_groups = kprobe_attr_groups, }; static int perf_kprobe_event_init(struct perf_event *event) @@ -8433,6 +8442,24 @@ static int perf_kprobe_event_init(struct perf_event *event) #endif /* CONFIG_KPROBE_EVENTS */ #ifdef CONFIG_UPROBE_EVENTS +PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); + +static struct attribute *uprobe_attrs[] = { + &format_attr_retprobe.attr, + &format_attr_ref_ctr_offset.attr, + NULL, +}; + +static struct attribute_group uprobe_format_group = { + .name = "format", + .attrs = uprobe_attrs, +}; + +static const struct attribute_group *uprobe_attr_groups[] = { + &uprobe_format_group, + NULL, +}; + static int perf_uprobe_event_init(struct perf_event *event); static struct pmu perf_uprobe = { .task_ctx_nr = perf_sw_context, @@ -8442,12 +8469,13 @@ static struct pmu perf_uprobe = { .start = perf_swevent_start, .stop = perf_swevent_stop, .read = perf_swevent_read, - .attr_groups = probe_attr_groups, + .attr_groups = uprobe_attr_groups, }; static int perf_uprobe_event_init(struct perf_event *event) { int err; + unsigned long ref_ctr_offset; bool is_retprobe; if (event->attr.type != perf_uprobe.type) @@ -8463,7 +8491,8 @@ static int perf_uprobe_event_init(struct perf_event *event) return -EOPNOTSUPP; is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; - err = perf_uprobe_init(event, is_retprobe); + ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; + err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); if (err) return err; diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c index 69a3fe926e8c..76217bbef815 100644 --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -290,7 +290,8 @@ void perf_kprobe_destroy(struct perf_event *p_event) #endif /* CONFIG_KPROBE_EVENTS */ #ifdef CONFIG_UPROBE_EVENTS -int perf_uprobe_init(struct perf_event *p_event, bool is_retprobe) +int perf_uprobe_init(struct perf_event *p_event, + unsigned long ref_ctr_offset, bool is_retprobe) { int ret; char *path = NULL; @@ -312,8 +313,8 @@ int perf_uprobe_init(struct perf_event *p_event, bool is_retprobe) goto out; } - tp_event = create_local_trace_uprobe( - path, p_event->attr.probe_offset, is_retprobe); + tp_event = create_local_trace_uprobe(path, p_event->attr.probe_offset, + ref_ctr_offset, is_retprobe); if (IS_ERR(tp_event)) { ret = PTR_ERR(tp_event); goto out; diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 5f52668e165d..03b10f3201a5 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -412,6 +412,7 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs, extern void destroy_local_trace_kprobe(struct trace_event_call *event_call); extern struct trace_event_call * -create_local_trace_uprobe(char *name, unsigned long offs, bool is_return); +create_local_trace_uprobe(char *name, unsigned long offs, + unsigned long ref_ctr_offset, bool is_return); extern void destroy_local_trace_uprobe(struct trace_event_call *event_call); #endif diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 3a7c73c40007..d09638706fe0 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -1405,7 +1405,8 @@ static int unregister_uprobe_event(struct trace_uprobe *tu) #ifdef CONFIG_PERF_EVENTS struct trace_event_call * -create_local_trace_uprobe(char *name, unsigned long offs, bool is_return) +create_local_trace_uprobe(char *name, unsigned long offs, + unsigned long ref_ctr_offset, bool is_return) { struct trace_uprobe *tu; struct path path; @@ -1437,6 +1438,7 @@ create_local_trace_uprobe(char *name, unsigned long offs, bool is_return) tu->offset = offs; tu->path = path; + tu->ref_ctr_offset = ref_ctr_offset; tu->filename = kstrdup(name, GFP_KERNEL); init_trace_event_call(tu, &tu->tp.call); -- 2.17.1