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 configuration like:
maps.my_pmy.event=evt Where evt is a predefined event with alias "evt". Signed-off-by: Wang Nan <wangn...@huawei.com> Signed-off-by: He Kuang <heku...@huawei.com> Cc: Arnaldo Carvalho de Melo <a...@redhat.com> Cc: Alexei Starovoitov <a...@plumgrid.com> Cc: Brendan Gregg <brendan.d.gr...@gmail.com> Cc: Daniel Borkmann <dan...@iogearbox.net> Cc: David Ahern <dsah...@gmail.com> Cc: He Kuang <heku...@huawei.com> Cc: Jiri Olsa <jo...@kernel.org> Cc: Kaixu Xia <xiaka...@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu...@hitachi.com> Cc: Namhyung Kim <namhy...@kernel.org> Cc: Paul Mackerras <pau...@samba.org> Cc: Peter Zijlstra <a.p.zijls...@chello.nl> Cc: Zefan Li <lize...@huawei.com> Cc: pi3or...@163.com Link: http://lkml.kernel.org/n/ebpf-36xcrahy9n0ayc05mu7aa...@git.kernel.org --- tools/perf/util/bpf-loader.c | 147 +++++++++++++++++++++++++++++++++++++++++++ tools/perf/util/bpf-loader.h | 39 ++++++++++++ 2 files changed, 186 insertions(+) diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c index 73ff9a9..b92c2f7 100644 --- a/tools/perf/util/bpf-loader.c +++ b/tools/perf/util/bpf-loader.c @@ -10,6 +10,7 @@ #include <linux/err.h> #include "perf.h" #include "debug.h" +#include "util.h" #include "bpf-loader.h" #include "bpf-prologue.h" #include "llvm-utils.h" @@ -633,6 +634,139 @@ int bpf__foreach_tev(struct bpf_object *obj, return 0; } +struct bpf_map_priv { + struct perf_evsel *evsel; +}; + +static void +bpf_map_priv__clear(struct bpf_map *map __maybe_unused, + void *_priv) +{ + struct bpf_map_priv *priv = _priv; + + free(priv); +} + +static int +bpf__config_obj_map_event(struct bpf_map *map, const char *val, + struct perf_evlist *evlist) +{ + struct bpf_map_priv *priv; + struct perf_evsel *evsel; + struct bpf_map_def def; + const char *map_name; + int err; + + map_name = bpf_map__get_name(map); + + evsel = perf_evlist__find_evsel_by_alias(evlist, val); + if (!evsel) { + pr_debug("Event '%s' doesn't exist\n", val); + return -EINVAL; + } + + err = bpf_map__get_def(map, &def); + if (err) { + pr_debug("Unable to get map definition from '%s'\n", + map_name); + return -EINVAL; + } + + if (def.type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) { + pr_debug("Map %s type is not BPF_MAP_TYPE_PERF_EVENT_ARRAY\n", + map_name); + return -EINVAL; + } + + priv = calloc(sizeof(*priv), 1); + if (!priv) { + pr_debug("No enough memory to alloc map private\n"); + return -ENOMEM; + } + + priv->evsel = evsel; + return bpf_map__set_private(map, priv, bpf_map_priv__clear); +} + +struct bpf_config_map_func { + const char *config_opt; + int (*config_func)(struct bpf_map *, const char *, + struct perf_evlist *); +}; + +struct bpf_config_map_func bpf_config_map_funcs[] = { + {"event", bpf__config_obj_map_event}, +}; + +static int +bpf__config_obj_map(struct bpf_object *obj, + const char *key, + const char *val, + struct perf_evlist *evlist) +{ + /* key is "maps.<mapname>.<config opt>" */ + char *map_name = strdup(key + sizeof("maps.") - 1); + struct bpf_map *map; + int err = -ENOENT; + 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", key); + 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); + goto out; + } + + for (i = 0; i < ARRAY_SIZE(bpf_config_map_funcs); i++) { + struct bpf_config_map_func *func = &bpf_config_map_funcs[i]; + + if (strcmp(map_opt, func->config_opt) == 0) { + err = func->config_func(map, val, evlist); + goto out; + } + } + + pr_debug("ERROR: invalid config option '%s' for maps\n", + map_opt); + err = -ENOENT; +out: + free(map_name); + return err; +} + +int bpf__config_obj(struct bpf_object *obj, + const char *key, + struct bpf_config_val *val, + struct perf_evlist *evlist) +{ + if (!obj || !key || !val) + return -ENODEV; + + if (!prefixcmp(key, "maps.")) { + if (val->type != BPF_CONFIG_VAL_STRING) { + pr_debug("ERROR: incorrect value type\n"); + return -EINVAL; + } + return bpf__config_obj_map(obj, key, val->string, evlist); + } + return -ENODEV; +} + #define bpf__strerror_head(err, buf, size) \ char sbuf[STRERR_BUFSIZE], *emsg;\ if (!size)\ @@ -675,3 +809,16 @@ int bpf__strerror_load(struct bpf_object *obj __maybe_unused, bpf__strerror_end(buf, size); return 0; } + +int bpf__strerror_config_obj(struct bpf_object *obj __maybe_unused, + const char *key, struct bpf_config_val *val, + struct perf_evlist *evlist __maybe_unused, + int err, char *buf, size_t size) +{ + bpf__strerror_head(err, buf, size); + bpf__strerror_entry(ENODEV, "Invalid config option: '%s'", key) + bpf__strerror_entry(ENOENT, "Config target in '%s' is invalid", key) + bpf__strerror_entry(EINVAL, "Invalid config value %s", val) + bpf__strerror_end(buf, size); + return 0; +} diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h index d8f1945..4c99b21 100644 --- a/tools/perf/util/bpf-loader.h +++ b/tools/perf/util/bpf-loader.h @@ -9,6 +9,7 @@ #include <linux/err.h> #include <string.h> #include "probe-event.h" +#include "evlist.h" #include "debug.h" struct bpf_object; @@ -17,6 +18,17 @@ struct bpf_object; typedef int (*bpf_prog_iter_callback_t)(struct probe_trace_event *tev, int fd, void *arg); +struct bpf_config_val { + enum { + BPF_CONFIG_VAL_STRING, + BPF_CONFIG_VAL_NUM, + } type; + union { + const char *string; + unsigned long long num; + }; +}; + #ifdef HAVE_LIBBPF_SUPPORT struct bpf_object *bpf__prepare_load(const char *filename, bool source); struct bpf_object *bpf__prepare_load_buffer(void *obj_buf, size_t obj_buf_sz, @@ -34,6 +46,13 @@ 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, const char *key, + struct bpf_config_val *val, struct perf_evlist *evlist); +int bpf__strerror_config_obj(struct bpf_object *obj, + const char *key, struct bpf_config_val *val, + struct perf_evlist *evlist, + int err, char *buf, size_t size); #else static inline struct bpf_object * bpf__prepare_load(const char *filename __maybe_unused, @@ -65,6 +84,15 @@ bpf__foreach_tev(struct bpf_object *obj __maybe_unused, } static inline int +bpf__config_obj(struct bpf_object *obj __maybe_unused, + const char *key __maybe_unused, + struct bpf_config_val *val __maybe_unused, + struct perf_evlist *evlist __maybe_unused) +{ + return 0; +} + +static inline int __bpf_strerror(char *buf, size_t size) { if (!size) @@ -90,5 +118,16 @@ 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, + const char *key __maybe_unused, + struct bpf_config_val *val __maybe_unused, + struct perf_evlist *evlist __maybe_unused, + int err __maybe_unused, + char *buf, size_t size) +{ + return __bpf_strerror(buf, size); +} #endif #endif -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
