From patchwork Thu Jan 14 13:40:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 12019571 X-Patchwork-Delegate: bpf@iogearbox.net 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=-14.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 B7366C4332D for ; Thu, 14 Jan 2021 13:42:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8C94C23A5F for ; Thu, 14 Jan 2021 13:42:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728824AbhANNmI convert rfc822-to-8bit (ORCPT ); Thu, 14 Jan 2021 08:42:08 -0500 Received: from us-smtp-delivery-44.mimecast.com ([205.139.111.44]:22631 "EHLO us-smtp-delivery-44.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729008AbhANNmH (ORCPT ); Thu, 14 Jan 2021 08:42:07 -0500 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-560-zekNGY1wPamDBjAyrEKhAA-1; Thu, 14 Jan 2021 08:41:11 -0500 X-MC-Unique: zekNGY1wPamDBjAyrEKhAA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 75D30190A7A1; Thu, 14 Jan 2021 13:41:09 +0000 (UTC) Received: from krava.redhat.com (unknown [10.40.195.188]) by smtp.corp.redhat.com (Postfix) with ESMTP id 12D3560C47; Thu, 14 Jan 2021 13:41:02 +0000 (UTC) From: Jiri Olsa To: Arnaldo Carvalho de Melo Cc: Peter Zijlstra , lkml , bpf@vger.kernel.org, Peter Zijlstra , Ingo Molnar , Mark Rutland , Namhyung Kim , Alexander Shishkin , Michael Petlan , Song Liu , Ian Rogers , Stephane Eranian , Alexei Budankov , Andi Kleen , Adrian Hunter Subject: [PATCH bpf-next 3/3] perf: Add build id data in mmap2 event Date: Thu, 14 Jan 2021 14:40:44 +0100 Message-Id: <20210114134044.1418404-4-jolsa@kernel.org> In-Reply-To: <20210114134044.1418404-1-jolsa@kernel.org> References: <20210114134044.1418404-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jolsa@kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Adding support to carry build id data in mmap2 event. The build id data replaces maj/min/ino/ino_generation fields, which are also used to identify map's binary, so it's ok to replace them with build id data: union { struct { u32 maj; u32 min; u64 ino; u64 ino_generation; }; struct { u8 build_id_size; u8 __reserved_1; u16 __reserved_2; u8 build_id[20]; }; }; Replaced maj/min/ino/ino_generation fields give us size of 24 bytes. We use 20 bytes for build id data, 1 byte for size and rest is unused. There's new misc bit for mmap2 to signal there's build id data in it: #define PERF_RECORD_MISC_MMAP_BUILD_ID (1 << 14) Acked-by: Peter Zijlstra (Intel) Signed-off-by: Jiri Olsa --- include/uapi/linux/perf_event.h | 42 +++++++++++++++++++++++++++++---- kernel/events/core.c | 32 +++++++++++++++++++++---- 2 files changed, 65 insertions(+), 9 deletions(-) diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index b15e3447cd9f..cb6f84103560 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -386,7 +386,8 @@ struct perf_event_attr { aux_output : 1, /* generate AUX records instead of events */ cgroup : 1, /* include cgroup events */ text_poke : 1, /* include text poke events */ - __reserved_1 : 30; + build_id : 1, /* use build id in mmap2 events */ + __reserved_1 : 29; union { __u32 wakeup_events; /* wakeup every n events */ @@ -659,6 +660,22 @@ struct perf_event_mmap_page { __u64 aux_size; }; +/* + * The current state of perf_event_header::misc bits usage: + * ('|' used bit, '-' unused bit) + * + * 012 CDEF + * |||---------|||| + * + * Where: + * 0-2 CPUMODE_MASK + * + * C PROC_MAP_PARSE_TIMEOUT + * D MMAP_DATA / COMM_EXEC / FORK_EXEC / SWITCH_OUT + * E MMAP_BUILD_ID / EXACT_IP / SCHED_OUT_PREEMPT + * F (reserved) + */ + #define PERF_RECORD_MISC_CPUMODE_MASK (7 << 0) #define PERF_RECORD_MISC_CPUMODE_UNKNOWN (0 << 0) #define PERF_RECORD_MISC_KERNEL (1 << 0) @@ -690,6 +707,7 @@ struct perf_event_mmap_page { * * PERF_RECORD_MISC_EXACT_IP - PERF_RECORD_SAMPLE of precise events * PERF_RECORD_MISC_SWITCH_OUT_PREEMPT - PERF_RECORD_SWITCH* events + * PERF_RECORD_MISC_MMAP_BUILD_ID - PERF_RECORD_MMAP2 event * * * PERF_RECORD_MISC_EXACT_IP: @@ -699,9 +717,13 @@ struct perf_event_mmap_page { * * PERF_RECORD_MISC_SWITCH_OUT_PREEMPT: * Indicates that thread was preempted in TASK_RUNNING state. + * + * PERF_RECORD_MISC_MMAP_BUILD_ID: + * Indicates that mmap2 event carries build id data. */ #define PERF_RECORD_MISC_EXACT_IP (1 << 14) #define PERF_RECORD_MISC_SWITCH_OUT_PREEMPT (1 << 14) +#define PERF_RECORD_MISC_MMAP_BUILD_ID (1 << 14) /* * Reserve the last bit to indicate some extended misc field */ @@ -915,10 +937,20 @@ enum perf_event_type { * u64 addr; * u64 len; * u64 pgoff; - * u32 maj; - * u32 min; - * u64 ino; - * u64 ino_generation; + * union { + * struct { + * u32 maj; + * u32 min; + * u64 ino; + * u64 ino_generation; + * }; + * struct { + * u8 build_id_size; + * u8 __reserved_1; + * u16 __reserved_2; + * u8 build_id[20]; + * }; + * }; * u32 prot, flags; * char filename[]; * struct sample_id sample_id; diff --git a/kernel/events/core.c b/kernel/events/core.c index 55d18791a72d..c37401e3e5f7 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -53,6 +53,7 @@ #include #include #include +#include #include "internal.h" @@ -397,6 +398,7 @@ static atomic_t nr_ksymbol_events __read_mostly; static atomic_t nr_bpf_events __read_mostly; static atomic_t nr_cgroup_events __read_mostly; static atomic_t nr_text_poke_events __read_mostly; +static atomic_t nr_build_id_events __read_mostly; static LIST_HEAD(pmus); static DEFINE_MUTEX(pmus_lock); @@ -4673,6 +4675,8 @@ static void unaccount_event(struct perf_event *event) dec = true; if (event->attr.mmap || event->attr.mmap_data) atomic_dec(&nr_mmap_events); + if (event->attr.build_id) + atomic_dec(&nr_build_id_events); if (event->attr.comm) atomic_dec(&nr_comm_events); if (event->attr.namespaces) @@ -8046,6 +8050,8 @@ struct perf_mmap_event { u64 ino; u64 ino_generation; u32 prot, flags; + u8 build_id[BUILD_ID_SIZE_MAX]; + u32 build_id_size; struct { struct perf_event_header header; @@ -8077,6 +8083,7 @@ static void perf_event_mmap_output(struct perf_event *event, struct perf_sample_data sample; int size = mmap_event->event_id.header.size; u32 type = mmap_event->event_id.header.type; + bool use_build_id; int ret; if (!perf_event_mmap_match(event, data)) @@ -8101,13 +8108,25 @@ static void perf_event_mmap_output(struct perf_event *event, mmap_event->event_id.pid = perf_event_pid(event, current); mmap_event->event_id.tid = perf_event_tid(event, current); + use_build_id = event->attr.build_id && mmap_event->build_id_size; + + if (event->attr.mmap2 && use_build_id) + mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_BUILD_ID; + perf_output_put(&handle, mmap_event->event_id); if (event->attr.mmap2) { - perf_output_put(&handle, mmap_event->maj); - perf_output_put(&handle, mmap_event->min); - perf_output_put(&handle, mmap_event->ino); - perf_output_put(&handle, mmap_event->ino_generation); + if (use_build_id) { + u8 size[4] = { (u8) mmap_event->build_id_size, 0, 0, 0 }; + + __output_copy(&handle, size, 4); + __output_copy(&handle, mmap_event->build_id, BUILD_ID_SIZE_MAX); + } else { + perf_output_put(&handle, mmap_event->maj); + perf_output_put(&handle, mmap_event->min); + perf_output_put(&handle, mmap_event->ino); + perf_output_put(&handle, mmap_event->ino_generation); + } perf_output_put(&handle, mmap_event->prot); perf_output_put(&handle, mmap_event->flags); } @@ -8236,6 +8255,9 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; + if (atomic_read(&nr_build_id_events)) + build_id_parse(vma, mmap_event->build_id, &mmap_event->build_id_size); + perf_iterate_sb(perf_event_mmap_output, mmap_event, NULL); @@ -11172,6 +11194,8 @@ static void account_event(struct perf_event *event) inc = true; if (event->attr.mmap || event->attr.mmap_data) atomic_inc(&nr_mmap_events); + if (event->attr.build_id) + atomic_inc(&nr_build_id_events); if (event->attr.comm) atomic_inc(&nr_comm_events); if (event->attr.namespaces)