From patchwork Fri Nov 13 12:29:12 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wang Nan X-Patchwork-Id: 56514 Delivered-To: patch@linaro.org Received: by 10.112.155.196 with SMTP id vy4csp1008821lbb; Fri, 13 Nov 2015 04:34:34 -0800 (PST) X-Received: by 10.68.96.226 with SMTP id dv2mr31321713pbb.127.1447418074244; Fri, 13 Nov 2015 04:34:34 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id ua7si27234767pac.65.2015.11.13.04.34.33; Fri, 13 Nov 2015 04:34:34 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932827AbbKMMeb (ORCPT + 28 others); Fri, 13 Nov 2015 07:34:31 -0500 Received: from szxga03-in.huawei.com ([119.145.14.66]:24534 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754732AbbKMMcA (ORCPT ); Fri, 13 Nov 2015 07:32:00 -0500 Received: from 172.24.1.47 (EHLO SZXEML423-HUB.china.huawei.com) ([172.24.1.47]) by szxrg03-dlp.huawei.com (MOS 4.4.3-GA FastPath queued) with ESMTP id BQY85710; Fri, 13 Nov 2015 20:29:47 +0800 (CST) Received: from linux-4hy3.site (10.107.193.248) by SZXEML423-HUB.china.huawei.com (10.82.67.154) with Microsoft SMTP Server id 14.3.235.1; Fri, 13 Nov 2015 20:29:34 +0800 From: Wang Nan To: , , CC: , , , Wang Nan , Arnaldo Carvalho de Melo Subject: [PATCH 03/12] perf tools: Allow BPF program attach to uprobe events Date: Fri, 13 Nov 2015 12:29:12 +0000 Message-ID: <1447417761-156094-4-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1447417761-156094-1-git-send-email-wangnan0@huawei.com> References: <1447417761-156094-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.107.193.248] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A090202.5645D82C.002F, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: dfaac563cc483908b09e586fb1d88055 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch appends new syntax to BPF object section name to support probing at uprobe event. Now we can use BPF program like this: SEC( "exec=/lib64/libc.so.6\n" "libcwrite=__write" ) int libcwrite(void *ctx) { return 1; } Where, in section name of a program, before the main config string, we can use 'key=value' style options. Now the only option key "exec" is for uprobe probing. Signed-off-by: Wang Nan Cc: Alexei Starovoitov Cc: Arnaldo Carvalho de Melo Cc: Masami Hiramatsu Cc: Zefan Li Cc: pi3orama@163.com --- tools/perf/util/bpf-loader.c | 122 ++++++++++++++++++++++++++++++++++++++++--- tools/perf/util/bpf-loader.h | 1 + 2 files changed, 117 insertions(+), 6 deletions(-) -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c index 4c50411..5f5505d 100644 --- a/tools/perf/util/bpf-loader.c +++ b/tools/perf/util/bpf-loader.c @@ -110,6 +110,115 @@ bpf_prog_priv__clear(struct bpf_program *prog __maybe_unused, } static int +config__exec(const char *value, struct perf_probe_event *pev) +{ + pev->uprobes = true; + pev->target = strdup(value); + return 0; +} + +static struct { + const char *key; + const char *usage; + const char *desc; + int (*func)(const char *, struct perf_probe_event *); +} bpf_config_terms[] = { + { + "exec", + "exec=", + "Set uprobe target", + config__exec, + }, +}; + +static int +do_config(const char *key, const char *value, + struct perf_probe_event *pev) +{ + unsigned int i; + + pr_debug("config bpf program: %s=%s\n", key, value); + for (i = 0; i < ARRAY_SIZE(bpf_config_terms); i++) + if (strcmp(key, bpf_config_terms[i].key) == 0) + return bpf_config_terms[i].func(value, pev); + + pr_debug("BPF: ERROR: invalid config option in object: %s=%s\n", + key, value); + + pr_debug("\nHint: Currently valid options are:\n"); + for (i = 0; i < ARRAY_SIZE(bpf_config_terms); i++) + pr_debug("\t%s:\t%s\n", bpf_config_terms[i].usage, + bpf_config_terms[i].desc); + pr_debug("\n"); + + return -BPF_LOADER_ERRNO__CONFIG_TERM; +} + +static const char * +parse_config_kvpair(const char *config_str, struct perf_probe_event *pev) +{ + char *text = strdup(config_str); + char *sep, *line; + const char *main_str = NULL; + int err = 0; + + if (!text) { + pr_debug("No enough memory: dup config_str failed\n"); + return ERR_PTR(-ENOMEM); + } + + line = text; + while ((sep = strchr(line, '\n'))) { + char *equ; + + *sep = '\0'; + equ = strchr(line, '='); + if (!equ) { + pr_warning("WARNING: invalid config in BPF object: %s\n", + line); + pr_warning("\tShould be 'key=value'.\n"); + goto nextline; + } + *equ = '\0'; + + err = do_config(line, equ + 1, pev); + if (err) + break; +nextline: + line = sep + 1; + } + + if (!err) + main_str = config_str + (line - text); + free(text); + + if (err) + return ERR_PTR(err); + + return main_str; +} + +static int +parse_config(const char *config_str, struct perf_probe_event *pev) +{ + const char *main_str; + int err; + + main_str = parse_config_kvpair(config_str, pev); + if (IS_ERR(main_str)) + return PTR_ERR(main_str); + + err = parse_perf_probe_command(main_str, pev); + if (err < 0) { + pr_debug("bpf: '%s' is not a valid config string\n", + config_str); + /* parse failed, don't need clear pev. */ + return -BPF_LOADER_ERRNO__CONFIG; + } + return 0; +} + +static int config_bpf_program(struct bpf_program *prog) { struct perf_probe_event *pev = NULL; @@ -131,13 +240,9 @@ config_bpf_program(struct bpf_program *prog) pev = &priv->pev; pr_debug("bpf: config program '%s'\n", config_str); - err = parse_perf_probe_command(config_str, pev); - if (err < 0) { - pr_debug("bpf: '%s' is not a valid config string\n", - config_str); - err = -BPF_LOADER_ERRNO__CONFIG; + err = parse_config(config_str, pev); + if (err) goto errout; - } if (pev->group && strcmp(pev->group, PERF_BPF_PROBE_GROUP)) { pr_debug("bpf: '%s': group for event is set and not '%s'.\n", @@ -340,6 +445,7 @@ static const char *bpf_loader_strerror_table[NR_ERRNO] = { [ERRCODE_OFFSET(EVENTNAME)] = "No event name found in config string", [ERRCODE_OFFSET(INTERNAL)] = "BPF loader internal error", [ERRCODE_OFFSET(COMPILE)] = "Error when compiling BPF scriptlet", + [ERRCODE_OFFSET(CONFIG_TERM)] = "Invalid config term in config string", }; static int @@ -420,6 +526,10 @@ int bpf__strerror_probe(struct bpf_object *obj __maybe_unused, int err, char *buf, size_t size) { bpf__strerror_head(err, buf, size); + case BPF_LOADER_ERRNO__CONFIG_TERM: { + scnprintf(buf, size, "%s (add -v to see detail)", emsg); + break; + } bpf__strerror_entry(EEXIST, "Probe point exist. Try use 'perf probe -d \"*\"'"); bpf__strerror_entry(EACCES, "You need to be root"); bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0"); diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h index 9caf3ae..d19f5c5 100644 --- a/tools/perf/util/bpf-loader.h +++ b/tools/perf/util/bpf-loader.h @@ -20,6 +20,7 @@ enum bpf_loader_errno { BPF_LOADER_ERRNO__EVENTNAME, /* Event name is missing */ BPF_LOADER_ERRNO__INTERNAL, /* BPF loader internal error */ BPF_LOADER_ERRNO__COMPILE, /* Error when compiling BPF scriptlet */ + BPF_LOADER_ERRNO__CONFIG_TERM, /* Invalid config term in config term */ __BPF_LOADER_ERRNO__END, };