From patchwork Mon Feb 22 09:10:30 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wang Nan X-Patchwork-Id: 62526 Delivered-To: patch@linaro.org Received: by 10.112.43.199 with SMTP id y7csp1121396lbl; Mon, 22 Feb 2016 01:38:16 -0800 (PST) X-Received: by 10.98.31.21 with SMTP id f21mr35804818pff.134.1456133896362; Mon, 22 Feb 2016 01:38:16 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id vy4si38642041pab.124.2016.02.22.01.38.16; Mon, 22 Feb 2016 01:38:16 -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 S1754083AbcBVJiM (ORCPT + 30 others); Mon, 22 Feb 2016 04:38:12 -0500 Received: from szxga01-in.huawei.com ([58.251.152.64]:53212 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751043AbcBVJNZ (ORCPT ); Mon, 22 Feb 2016 04:13:25 -0500 Received: from 172.24.1.47 (EHLO szxeml431-hub.china.huawei.com) ([172.24.1.47]) by szxrg01-dlp.huawei.com (MOS 4.3.7-GA FastPath queued) with ESMTP id DEY60677; Mon, 22 Feb 2016 17:11:39 +0800 (CST) Received: from linux-4hy3.site (10.107.193.248) by szxeml431-hub.china.huawei.com (10.82.67.208) with Microsoft SMTP Server id 14.3.235.1; Mon, 22 Feb 2016 17:11:23 +0800 From: Wang Nan To: Alexei Starovoitov , Arnaldo Carvalho de Melo , Arnaldo Carvalho de Melo , Brendan Gregg CC: Adrian Hunter , Cody P Schafer , "David S. Miller" , He Kuang , =?UTF-8?q?J=C3=A9r=C3=A9mie=20Galarneau?= , Jiri Olsa , Kirill Smelkov , Li Zefan , Masami Hiramatsu , Namhyung Kim , Peter Zijlstra , , Wang Nan , Subject: [PATCH 03/48] perf bpf: Add API to set values to map entries in a bpf object Date: Mon, 22 Feb 2016 09:10:30 +0000 Message-ID: <1456132275-98875-4-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1456132275-98875-1-git-send-email-wangnan0@huawei.com> References: <1456132275-98875-1-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=0001.0A020206.56CAD0CD.006E, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 033ab4a3bfd7d210d94240fbf8a4bb24 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org bpf__config_obj() is introduced as a core API to config BPF object after loading. One configuration option of maps is introduced. After this patch BPF object can accept assignments like: map:my_map.value=1234 (map.my_map.value looks pretty. However, there's a small but hard to fix problem related to flex's greedy matching. Please see [1]. Choose ':' to avoid it in a simpler way.) This patch is more complex than the work it does because the consideration of extension. In designing BPF map configuration, the following things should be considered: 1. Array indices selection: perf should allow user setting different value for different slots in an array, with syntax like: map:my_map.value[0,3...6]=1234; 2. A map should be set by different config terms, each for a part of it. For example, set each slot to the pid of a thread; 3. Type of value: integer is not the only valid value type. A perf counter can also be put into a map after commit 35578d798400 ("bpf: Implement function bpf_perf_event_read() that get the selected hardware PMU counter") 4. For a hash table, it should be possible to use a string or other value as a key; 5. It is possible that map configuration is unable to be setup during parsing. A perf counter is an example. Therefore, this patch does the following: 1. Instead of updating map element during parsing, this patch stores map config options in 'struct bpf_map_priv'. Following patches will apply those configs at an appropriate time; 2. Link map operations in a list so a map can have multiple config terms attached, so different parts can be configured separately; 3. Make 'struct bpf_map_priv' extensible so that the following patches can add new types of keys and operations; 4. Use bpf_obj_config__map_funcs array to support more map config options. Since the patch changing the event parser to parse BPF object config is relative large, I've put it in another commit. Code in this patch can be tested after applying the next patch. [1] http://lkml.kernel.org/g/564ED621.4050500@huawei.com Signed-off-by: Wang Nan Cc: Adrian Hunter Cc: Alexei Starovoitov Cc: Brendan Gregg Cc: Cody P Schafer Cc: He Kuang Cc: Jeremie Galarneau Cc: Jiri Olsa Cc: Kirill Smelkov Cc: Li Zefan Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1454680939-24963-7-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang [ Changes "maps:my_map.value" to "map:my_map.value", improved error messages ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/bpf-loader.c | 276 +++++++++++++++++++++++++++++++++++++++++++ tools/perf/util/bpf-loader.h | 38 ++++++ 2 files changed, 314 insertions(+) -- 1.8.3.4 diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c index 0bdccf4..caeef9e 100644 --- a/tools/perf/util/bpf-loader.c +++ b/tools/perf/util/bpf-loader.c @@ -739,6 +739,261 @@ int bpf__foreach_tev(struct bpf_object *obj, return 0; } +enum bpf_map_op_type { + BPF_MAP_OP_SET_VALUE, +}; + +enum bpf_map_key_type { + BPF_MAP_KEY_ALL, +}; + +struct bpf_map_op { + struct list_head list; + enum bpf_map_op_type op_type; + enum bpf_map_key_type key_type; + union { + u64 value; + } v; +}; + +struct bpf_map_priv { + struct list_head ops_list; +}; + +static void +bpf_map_op__delete(struct bpf_map_op *op) +{ + if (!list_empty(&op->list)) + list_del(&op->list); + free(op); +} + +static void +bpf_map_priv__purge(struct bpf_map_priv *priv) +{ + struct bpf_map_op *pos, *n; + + list_for_each_entry_safe(pos, n, &priv->ops_list, list) { + list_del_init(&pos->list); + bpf_map_op__delete(pos); + } +} + +static void +bpf_map_priv__clear(struct bpf_map *map __maybe_unused, + void *_priv) +{ + struct bpf_map_priv *priv = _priv; + + bpf_map_priv__purge(priv); + free(priv); +} + +static struct bpf_map_op * +bpf_map_op__new(void) +{ + struct bpf_map_op *op; + + op = zalloc(sizeof(*op)); + if (!op) { + pr_debug("Failed to alloc bpf_map_op\n"); + return ERR_PTR(-ENOMEM); + } + INIT_LIST_HEAD(&op->list); + + op->key_type = BPF_MAP_KEY_ALL; + return op; +} + +static int +bpf_map__add_op(struct bpf_map *map, struct bpf_map_op *op) +{ + struct bpf_map_priv *priv; + const char *map_name; + int err; + + map_name = bpf_map__get_name(map); + err = bpf_map__get_private(map, (void **)&priv); + if (err) { + pr_debug("Failed to get private from map %s\n", map_name); + return err; + } + + if (!priv) { + priv = zalloc(sizeof(*priv)); + if (!priv) { + pr_debug("No enough memory to alloc map private\n"); + return -ENOMEM; + } + INIT_LIST_HEAD(&priv->ops_list); + + if (bpf_map__set_private(map, priv, bpf_map_priv__clear)) { + free(priv); + return -BPF_LOADER_ERRNO__INTERNAL; + } + } + + list_add_tail(&op->list, &priv->ops_list); + return 0; +} + +static int +__bpf_map__config_value(struct bpf_map *map, + struct parse_events_term *term) +{ + struct bpf_map_def def; + struct bpf_map_op *op; + const char *map_name; + int err; + + map_name = bpf_map__get_name(map); + + err = bpf_map__get_def(map, &def); + if (err) { + pr_debug("Unable to get map definition from '%s'\n", + map_name); + return -BPF_LOADER_ERRNO__INTERNAL; + } + + if (def.type != BPF_MAP_TYPE_ARRAY) { + pr_debug("Map %s type is not BPF_MAP_TYPE_ARRAY\n", + map_name); + return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE; + } + if (def.key_size < sizeof(unsigned int)) { + pr_debug("Map %s has incorrect key size\n", map_name); + return -BPF_LOADER_ERRNO__OBJCONF_MAP_KEYSIZE; + } + switch (def.value_size) { + case 1: + case 2: + case 4: + case 8: + break; + default: + pr_debug("Map %s has incorrect value size\n", map_name); + return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE; + } + + op = bpf_map_op__new(); + if (IS_ERR(op)) + return PTR_ERR(op); + op->op_type = BPF_MAP_OP_SET_VALUE; + op->v.value = term->val.num; + + err = bpf_map__add_op(map, op); + if (err) + bpf_map_op__delete(op); + return err; +} + +static int +bpf_map__config_value(struct bpf_map *map, + struct parse_events_term *term, + struct perf_evlist *evlist __maybe_unused) +{ + if (!term->err_val) { + pr_debug("Config value not set\n"); + return -BPF_LOADER_ERRNO__OBJCONF_CONF; + } + + if (term->type_val != PARSE_EVENTS__TERM_TYPE_NUM) { + pr_debug("ERROR: wrong value type\n"); + return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE; + } + + return __bpf_map__config_value(map, term); +} + +struct bpf_obj_config__map_func { + const char *config_opt; + int (*config_func)(struct bpf_map *, struct parse_events_term *, + struct perf_evlist *); +}; + +struct bpf_obj_config__map_func bpf_obj_config__map_funcs[] = { + {"value", bpf_map__config_value}, +}; + +static int +bpf__obj_config_map(struct bpf_object *obj, + struct parse_events_term *term, + struct perf_evlist *evlist, + int *key_scan_pos) +{ + /* key is "map:." */ + char *map_name = strdup(term->config + sizeof("map:") - 1); + struct bpf_map *map; + int err = -BPF_LOADER_ERRNO__OBJCONF_OPT; + char *map_opt; + size_t i; + + if (!map_name) + return -ENOMEM; + + map_opt = strchr(map_name, '.'); + if (!map_opt) { + pr_debug("ERROR: Invalid map config: %s\n", map_name); + goto out; + } + + *map_opt++ = '\0'; + if (*map_opt == '\0') { + pr_debug("ERROR: Invalid map option: %s\n", term->config); + goto out; + } + + map = bpf_object__get_map_by_name(obj, map_name); + if (!map) { + pr_debug("ERROR: Map %s doesn't exist\n", map_name); + err = -BPF_LOADER_ERRNO__OBJCONF_MAP_NOTEXIST; + goto out; + } + + *key_scan_pos += map_opt - map_name; + for (i = 0; i < ARRAY_SIZE(bpf_obj_config__map_funcs); i++) { + struct bpf_obj_config__map_func *func = + &bpf_obj_config__map_funcs[i]; + + if (strcmp(map_opt, func->config_opt) == 0) { + err = func->config_func(map, term, evlist); + goto out; + } + } + + pr_debug("ERROR: Invalid map config option '%s'\n", map_opt); + err = -BPF_LOADER_ERRNO__OBJCONF_MAP_OPT; +out: + free(map_name); + if (!err) + key_scan_pos += strlen(map_opt); + return err; +} + +int bpf__config_obj(struct bpf_object *obj, + struct parse_events_term *term, + struct perf_evlist *evlist, + int *error_pos) +{ + int key_scan_pos = 0; + int err; + + if (!obj || !term || !term->config) + return -EINVAL; + + if (!prefixcmp(term->config, "map:")) { + key_scan_pos = sizeof("map:") - 1; + err = bpf__obj_config_map(obj, term, evlist, &key_scan_pos); + goto out; + } + err = -BPF_LOADER_ERRNO__OBJCONF_OPT; +out: + if (error_pos) + *error_pos = key_scan_pos; + return err; + +} + #define ERRNO_OFFSET(e) ((e) - __BPF_LOADER_ERRNO__START) #define ERRCODE_OFFSET(c) ERRNO_OFFSET(BPF_LOADER_ERRNO__##c) #define NR_ERRNO (__BPF_LOADER_ERRNO__END - __BPF_LOADER_ERRNO__START) @@ -753,6 +1008,14 @@ static const char *bpf_loader_strerror_table[NR_ERRNO] = { [ERRCODE_OFFSET(PROLOGUE)] = "Failed to generate prologue", [ERRCODE_OFFSET(PROLOGUE2BIG)] = "Prologue too big for program", [ERRCODE_OFFSET(PROLOGUEOOB)] = "Offset out of bound for prologue", + [ERRCODE_OFFSET(OBJCONF_OPT)] = "Invalid object config option", + [ERRCODE_OFFSET(OBJCONF_CONF)] = "Config value not set (missing '=')", + [ERRCODE_OFFSET(OBJCONF_MAP_OPT)] = "Invalid object map config option", + [ERRCODE_OFFSET(OBJCONF_MAP_NOTEXIST)] = "Target map doesn't exist", + [ERRCODE_OFFSET(OBJCONF_MAP_VALUE)] = "Incorrect value type for map", + [ERRCODE_OFFSET(OBJCONF_MAP_TYPE)] = "Incorrect map type", + [ERRCODE_OFFSET(OBJCONF_MAP_KEYSIZE)] = "Incorrect map key size", + [ERRCODE_OFFSET(OBJCONF_MAP_VALUESIZE)] = "Incorrect map value size", }; static int @@ -872,3 +1135,16 @@ int bpf__strerror_load(struct bpf_object *obj, bpf__strerror_end(buf, size); return 0; } + +int bpf__strerror_config_obj(struct bpf_object *obj __maybe_unused, + struct parse_events_term *term __maybe_unused, + struct perf_evlist *evlist __maybe_unused, + int *error_pos __maybe_unused, int err, + char *buf, size_t size) +{ + bpf__strerror_head(err, buf, size); + bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE, + "Can't use this config term with this map type"); + bpf__strerror_end(buf, size); + return 0; +} diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h index 6fdc045..cc46a07 100644 --- a/tools/perf/util/bpf-loader.h +++ b/tools/perf/util/bpf-loader.h @@ -10,6 +10,7 @@ #include #include #include "probe-event.h" +#include "evlist.h" #include "debug.h" enum bpf_loader_errno { @@ -24,10 +25,19 @@ enum bpf_loader_errno { BPF_LOADER_ERRNO__PROLOGUE, /* Failed to generate prologue */ BPF_LOADER_ERRNO__PROLOGUE2BIG, /* Prologue too big for program */ BPF_LOADER_ERRNO__PROLOGUEOOB, /* Offset out of bound for prologue */ + BPF_LOADER_ERRNO__OBJCONF_OPT, /* Invalid object config option */ + BPF_LOADER_ERRNO__OBJCONF_CONF, /* Config value not set (lost '=')) */ + BPF_LOADER_ERRNO__OBJCONF_MAP_OPT, /* Invalid object map config option */ + BPF_LOADER_ERRNO__OBJCONF_MAP_NOTEXIST, /* Target map not exist */ + BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE, /* Incorrect value type for map */ + BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE, /* Incorrect map type */ + BPF_LOADER_ERRNO__OBJCONF_MAP_KEYSIZE, /* Incorrect map key size */ + BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE,/* Incorrect map value size */ __BPF_LOADER_ERRNO__END, }; struct bpf_object; +struct parse_events_term; #define PERF_BPF_PROBE_GROUP "perf_bpf_probe" typedef int (*bpf_prog_iter_callback_t)(struct probe_trace_event *tev, @@ -53,6 +63,14 @@ int bpf__strerror_load(struct bpf_object *obj, int err, char *buf, size_t size); int bpf__foreach_tev(struct bpf_object *obj, bpf_prog_iter_callback_t func, void *arg); + +int bpf__config_obj(struct bpf_object *obj, struct parse_events_term *term, + struct perf_evlist *evlist, int *error_pos); +int bpf__strerror_config_obj(struct bpf_object *obj, + struct parse_events_term *term, + struct perf_evlist *evlist, + int *error_pos, int err, char *buf, + size_t size); #else static inline struct bpf_object * bpf__prepare_load(const char *filename __maybe_unused, @@ -84,6 +102,15 @@ bpf__foreach_tev(struct bpf_object *obj __maybe_unused, } static inline int +bpf__config_obj(struct bpf_object *obj __maybe_unused, + struct parse_events_term *term __maybe_unused, + struct perf_evlist *evlist __maybe_unused, + int *error_pos __maybe_unused) +{ + return 0; +} + +static inline int __bpf_strerror(char *buf, size_t size) { if (!size) @@ -118,5 +145,16 @@ static inline int bpf__strerror_load(struct bpf_object *obj __maybe_unused, { return __bpf_strerror(buf, size); } + +static inline int +bpf__strerror_config_obj(struct bpf_object *obj __maybe_unused, + struct parse_events_term *term __maybe_unused, + struct perf_evlist *evlist __maybe_unused, + int *error_pos __maybe_unused, + int err __maybe_unused, + char *buf, size_t size) +{ + return __bpf_strerror(buf, size); +} #endif #endif