From patchwork Wed Nov 29 07:20:35 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yonghong Song X-Patchwork-Id: 842481 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.b="fF2brNud"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3ymsQ66Lsgz9ryr for ; Wed, 29 Nov 2017 18:20:46 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751844AbdK2HUj (ORCPT ); Wed, 29 Nov 2017 02:20:39 -0500 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:60508 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751165AbdK2HUi (ORCPT ); Wed, 29 Nov 2017 02:20:38 -0500 Received: from pps.filterd (m0109333.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id vAT7JYDA015161 for ; Tue, 28 Nov 2017 23:20:38 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=facebook; bh=zXzdUmBh3bOEvXohPQhiiAVvIygXgzSIOLHB5oRMm+Q=; b=fF2brNudg7JbUgsWpNInuPorkAq+s8MNj3Ar6sF5Ouu5FRe/iIENU9wcyn9SzuaffM1f zisiehTQIjeKkSUb2D2ZIavt2oLOj0CD/BJZz1JAXJikTN4OtfR1ah4iXowAcwqOaQ0E 4TpXEjXN9lv6Ce1Av6HQVzlOJuRDNSBBP18= Received: from mail.thefacebook.com ([199.201.64.23]) by mx0a-00082601.pphosted.com with ESMTP id 2ehn9b8cbj-2 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Tue, 28 Nov 2017 23:20:37 -0800 Received: from mx-out.facebook.com (192.168.52.123) by PRN-CHUB14.TheFacebook.com (192.168.16.24) with Microsoft SMTP Server id 14.3.361.1; Tue, 28 Nov 2017 23:20:36 -0800 Received: by devbig474.prn1.facebook.com (Postfix, from userid 128203) id A2912E414B3; Tue, 28 Nov 2017 23:20:36 -0800 (PST) Smtp-Origin-Hostprefix: devbig From: Yonghong Song Smtp-Origin-Hostname: devbig474.prn1.facebook.com To: , , , , , CC: Smtp-Origin-Cluster: prn1c29 Subject: [PATCH net-next 1/2] bpf/tracing: allow user space to query prog array on the same tp Date: Tue, 28 Nov 2017 23:20:35 -0800 Message-ID: <20171129072036.467246-2-yhs@fb.com> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20171129072036.467246-1-yhs@fb.com> References: <20171129072036.467246-1-yhs@fb.com> X-FB-Internal: Safe MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-11-29_02:, , signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Commit e87c6bc3852b ("bpf: permit multiple bpf attachments for a single perf event") added support to attach multiple bpf programs to a single perf event. Commit 2541517c32be ("tracing, perf: Implement BPF programs attached to kprobes") utilized the existing perf ioctl interface and added the command PERF_EVENT_IOC_SET_BPF to attach a bpf program to a tracepoint. This patch adds a new ioctl command, given a perf event fd, to query the bpf program array attached to the same perf tracepoint event. The new uapi ioctl command: PERF_EVENT_IOC_QUERY_BPF The new uapi/linux/perf_event.h structure: struct perf_event_query_bpf { __u64 prog_ids; __u32 prog_cnt; }; The usage: struct perf_event_query_bpf query; query.prog_ids = (__u64)usr_prog_ids_buf; query.prog_cnt = usr_prog_ids_buf_len; err = ioctl(pmu_efd, PERF_EVENT_IOC_QUERY_BPF, &query); Signed-off-by: Yonghong Song --- include/linux/bpf.h | 4 ++++ include/uapi/linux/perf_event.h | 6 ++++++ kernel/bpf/core.c | 24 ++++++++++++++++++++++++ kernel/events/core.c | 3 +++ kernel/trace/bpf_trace.c | 23 +++++++++++++++++++++++ 5 files changed, 60 insertions(+) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index e55e425..f812ac5 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -254,6 +254,7 @@ typedef unsigned long (*bpf_ctx_copy_t)(void *dst, const void *src, u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size, void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy); +int bpf_event_query_prog_array(struct perf_event *event, void __user *info); int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, union bpf_attr __user *uattr); @@ -285,6 +286,9 @@ int bpf_prog_array_copy_to_user(struct bpf_prog_array __rcu *progs, void bpf_prog_array_delete_safe(struct bpf_prog_array __rcu *progs, struct bpf_prog *old_prog); +int bpf_prog_array_copy_info(struct bpf_prog_array __rcu *array, + __u32 __user *prog_ids, u32 request_cnt, + __u32 __user *prog_cnt); int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array, struct bpf_prog *exclude_prog, struct bpf_prog *include_prog, diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index b9a4953..fee0b43 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -418,6 +418,11 @@ struct perf_event_attr { __u16 __reserved_2; /* align to __u64 */ }; +struct perf_event_query_bpf { + __u64 prog_ids; + __u32 prog_cnt; +}; + #define perf_flags(attr) (*(&(attr)->read_format + 1)) /* @@ -433,6 +438,7 @@ struct perf_event_attr { #define PERF_EVENT_IOC_ID _IOR('$', 7, __u64 *) #define PERF_EVENT_IOC_SET_BPF _IOW('$', 8, __u32) #define PERF_EVENT_IOC_PAUSE_OUTPUT _IOW('$', 9, __u32) +#define PERF_EVENT_IOC_QUERY_BPF _IOWR('$', 10, struct perf_event_query_bpf *) enum perf_event_ioc_flags { PERF_IOC_FLAG_GROUP = 1U << 0, diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index b9f8686..40e3b8d 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -1461,6 +1461,8 @@ int bpf_prog_array_copy_to_user(struct bpf_prog_array __rcu *progs, rcu_read_lock(); prog = rcu_dereference(progs)->progs; for (; *prog; prog++) { + if (*prog == &dummy_bpf_prog.prog) + continue; id = (*prog)->aux->id; if (copy_to_user(prog_ids + i, &id, sizeof(id))) { rcu_read_unlock(); @@ -1544,6 +1546,28 @@ int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array, return 0; } +int bpf_prog_array_copy_info(struct bpf_prog_array __rcu *array, + __u32 __user *prog_ids, u32 request_cnt, + __u32 __user *prog_cnt) +{ + struct bpf_prog **prog; + u32 cnt = 0; + + if (array) { + for (prog = array->progs; *prog; prog++) + if (*prog != &dummy_bpf_prog.prog) + cnt++; + } + + if (copy_to_user(prog_cnt, &cnt, sizeof(cnt))) + return -EFAULT; + + if (cnt == 0) + return 0; + + return bpf_prog_array_copy_to_user(array, prog_ids, request_cnt); +} + static void bpf_prog_free_deferred(struct work_struct *work) { struct bpf_prog_aux *aux; diff --git a/kernel/events/core.c b/kernel/events/core.c index 9404c63..93aec2c 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4723,6 +4723,9 @@ static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned lon rcu_read_unlock(); return 0; } + + case PERF_EVENT_IOC_QUERY_BPF: + return bpf_event_query_prog_array(event, (void __user *)arg); default: return -ENOTTY; } diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 27d1f4f..7fb7f74 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -812,3 +812,26 @@ void perf_event_detach_bpf_prog(struct perf_event *event) unlock: mutex_unlock(&bpf_event_mutex); } + +int bpf_event_query_prog_array(struct perf_event *event, void __user *info) +{ + struct perf_event_query_bpf __user *uquery = info; + struct perf_event_query_bpf query = {}; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (event->attr.type != PERF_TYPE_TRACEPOINT) + return -EINVAL; + if (copy_from_user(&query, uquery, sizeof(query))) + return -EFAULT; + + mutex_lock(&bpf_event_mutex); + ret = bpf_prog_array_copy_info(event->tp_event->prog_array, + u64_to_user_ptr(query.prog_ids), + query.prog_cnt, + &uquery->prog_cnt); + mutex_unlock(&bpf_event_mutex); + + return ret; +} From patchwork Wed Nov 29 07:20:36 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yonghong Song X-Patchwork-Id: 842482 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.b="XNFERiKW"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3ymsQB1zkSz9ryr for ; Wed, 29 Nov 2017 18:20:50 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752075AbdK2HUs (ORCPT ); Wed, 29 Nov 2017 02:20:48 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:44734 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751676AbdK2HUj (ORCPT ); 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Tue, 28 Nov 2017 23:20:36 -0800 Received: by devbig474.prn1.facebook.com (Postfix, from userid 128203) id 9344BE41482; Tue, 28 Nov 2017 23:20:36 -0800 (PST) Smtp-Origin-Hostprefix: devbig From: Yonghong Song Smtp-Origin-Hostname: devbig474.prn1.facebook.com To: , , , , , CC: Smtp-Origin-Cluster: prn1c29 Subject: [PATCH net-next 2/2] bpf/tracing: add a bpf test for new ioctl query interface Date: Tue, 28 Nov 2017 23:20:36 -0800 Message-ID: <20171129072036.467246-3-yhs@fb.com> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20171129072036.467246-1-yhs@fb.com> References: <20171129072036.467246-1-yhs@fb.com> X-FB-Internal: Safe MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-11-29_02:, , signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Added a subtest in test_progs. The tracepoint is sched/sched_switch. Multiple bpf programs are attached to this tracepoint and the query interface is exercised. Signed-off-by: Yonghong Song --- tools/include/uapi/linux/perf_event.h | 6 ++ tools/testing/selftests/bpf/Makefile | 2 +- tools/testing/selftests/bpf/test_progs.c | 107 +++++++++++++++++++++++++++++++ 3 files changed, 114 insertions(+), 1 deletion(-) diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h index 362493a..8523db0 100644 --- a/tools/include/uapi/linux/perf_event.h +++ b/tools/include/uapi/linux/perf_event.h @@ -418,6 +418,11 @@ struct perf_event_attr { __u16 __reserved_2; /* align to __u64 */ }; +struct perf_event_query_bpf { + __u64 prog_ids; + __u32 prog_cnt; +}; + #define perf_flags(attr) (*(&(attr)->read_format + 1)) /* @@ -433,6 +438,7 @@ struct perf_event_attr { #define PERF_EVENT_IOC_ID _IOR('$', 7, __u64 *) #define PERF_EVENT_IOC_SET_BPF _IOW('$', 8, __u32) #define PERF_EVENT_IOC_PAUSE_OUTPUT _IOW('$', 9, __u32) +#define PERF_EVENT_IOC_QUERY_BPF _IOWR('$', 10, struct perf_event_query_bpf *) enum perf_event_ioc_flags { PERF_IOC_FLAG_GROUP = 1U << 0, diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 333a486..c49c08a 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -17,7 +17,7 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test_obj_id.o \ test_pkt_md_access.o test_xdp_redirect.o test_xdp_meta.o sockmap_parse_prog.o \ - sockmap_verdict_prog.o dev_cgroup.o + sockmap_verdict_prog.o dev_cgroup.o test_tracepoint.o TEST_PROGS := test_kmod.sh test_xdp_redirect.sh test_xdp_meta.sh diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c index 6942753..39e7f7e 100644 --- a/tools/testing/selftests/bpf/test_progs.c +++ b/tools/testing/selftests/bpf/test_progs.c @@ -21,8 +21,10 @@ typedef __u16 __sum16; #include #include #include +#include #include +#include #include #include #include @@ -617,6 +619,110 @@ static void test_obj_name(void) } } +static void test_tp_attach_query(void) +{ + const char *file = "./test_tracepoint.o"; + const int num_progs = 3; + __u32 duration = 0, info_len, prog_ids[num_progs], saved_prog_ids[num_progs]; + int i, j, bytes, efd, err, prog_fd[num_progs], pmu_fd[num_progs]; + struct perf_event_query_bpf query = {}; + struct perf_event_attr attr = {}; + struct bpf_object *obj[num_progs]; + struct bpf_prog_info prog_info; + char buf[256]; + + snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/sched/sched_switch/id"); + efd = open(buf, O_RDONLY, 0); + if (CHECK(efd < 0, "open", "err %d errno %d\n", efd, errno)) + return; + bytes = read(efd, buf, sizeof(buf)); + close(efd); + if (CHECK(bytes <= 0 || bytes >= sizeof(buf), "read", "bytes %d errno %d\n", bytes, errno)) + return; + + attr.config = strtol(buf, NULL, 0); + attr.type = PERF_TYPE_TRACEPOINT; + attr.sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_CALLCHAIN; + attr.sample_period = 1; + attr.wakeup_events = 1; + + for (i = 0; i < num_progs; i++) { + err = bpf_prog_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj[i], &prog_fd[i]); + if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno)) + goto cleanup1; + + bzero(&prog_info, sizeof(prog_info)); + prog_info.jited_prog_len = 0; + prog_info.xlated_prog_len = 0; + prog_info.nr_map_ids = 0; + info_len = sizeof(prog_info); + err = bpf_obj_get_info_by_fd(prog_fd[i], &prog_info, &info_len); + if (CHECK(err, "bpf_obj_get_info_by_fd", "err %d errno %d\n", err, errno)) + goto cleanup1; + saved_prog_ids[i] = prog_info.id; + + pmu_fd[i] = syscall(__NR_perf_event_open, &attr, -1 /* pid */, 0 /* cpu 0 */, + -1 /* group id */, 0 /* flags */); + if (CHECK(pmu_fd[i] < 0, "perf_event_open", "err %d errno %d\n", pmu_fd[i], errno)) + goto cleanup2; + err = ioctl(pmu_fd[i], PERF_EVENT_IOC_ENABLE, 0); + if (CHECK(err, "perf_event_ioc_enable", "err %d errno %d\n", err, errno)) + goto cleanup3; + + if (i == 0) { + /* check NULL prog array query */ + query.prog_ids = (__u64)prog_ids; + query.prog_cnt = num_progs; + err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, &query); + if (CHECK(err || query.prog_cnt != 0, "perf_event_ioc_query_bpf", + "err %d errno %d query.prog_cnt %u\n", err, errno, query.prog_cnt)) + goto cleanup3; + } + + err = ioctl(pmu_fd[i], PERF_EVENT_IOC_SET_BPF, prog_fd[i]); + if (CHECK(err, "perf_event_ioc_set_bpf", "err %d errno %d\n", err, errno)) + goto cleanup3; + + if (i == 1) { + /* do a few negative tests */ + query.prog_ids = 0; + query.prog_cnt = num_progs; + err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, &query); + if (CHECK(!err || errno != EFAULT, "perf_event_ioc_query_bpf", + "err %d errno %d query.prog_cnt %u\n", err, errno, query.prog_cnt)) + goto cleanup3; + + query.prog_ids = (__u64)prog_ids; + query.prog_cnt = 1; + err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, &query); + if (CHECK(!err || errno != ENOSPC, "perf_event_ioc_query_bpf", + "err %d errno %d query.prog_cnt %u\n", err, errno, query.prog_cnt)) + goto cleanup3; + } + + query.prog_ids = (__u64)prog_ids; + query.prog_cnt = num_progs; + err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, &query); + if (CHECK(err || query.prog_cnt != (i + 1), "perf_event_ioc_query_bpf", + "err %d errno %d query.prog_cnt %u\n", err, errno, query.prog_cnt)) + goto cleanup3; + for (j = 0; j < i + 1; j++) + if (CHECK(saved_prog_ids[j] != prog_ids[j], "perf_event_ioc_query_bpf", + "#%d saved_prog_id %x query prog_id %x\n", j, saved_prog_ids[j], prog_ids[j])) + goto cleanup3; + } + + i = num_progs - 1; + for (; i >= 0; i--) { + cleanup3: + ioctl(pmu_fd[i], PERF_EVENT_IOC_DISABLE); + cleanup2: + close(pmu_fd[i]); + cleanup1: + bpf_object__close(obj[i]); + } +} + int main(void) { struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY }; @@ -630,6 +736,7 @@ int main(void) test_bpf_obj_id(); test_pkt_md_access(); test_obj_name(); + test_tp_attach_query(); printf("Summary: %d PASSED, %d FAILED\n", pass_cnt, error_cnt); return error_cnt ? EXIT_FAILURE : EXIT_SUCCESS;