From 2d055bf253c0d606c5de3fe7749e3188080780ad Mon Sep 17 00:00:00 2001 From: Wang Nan Date: Mon, 22 Feb 2016 09:10:34 +0000 Subject: [PATCH] perf tools: Support setting different slots in a BPF map separately This patch introduces basic facilities to support config different slots in a BPF map one by one. array.nr_ranges and array.ranges are introduced into 'struct parse_events_term', where ranges is an array of indices range (start, length) which will be configured by this config term. nr_ranges is the size of the array. The array is passed to 'struct bpf_map_priv'. To indicate the new type of configuration, BPF_MAP_KEY_RANGES is added as a new key type. bpf_map_config_foreach_key() is extended to iterate over those indices instead of all possible keys. Code in this commit will be enabled by following commit which enables the indices syntax for array configuration. 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/1456132275-98875-8-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/bpf-loader.c | 128 ++++++++++++++++++++++++++++++++++++++--- tools/perf/util/bpf-loader.h | 1 + tools/perf/util/parse-events.c | 7 +++ tools/perf/util/parse-events.h | 10 ++++ 4 files changed, 137 insertions(+), 9 deletions(-) diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c index deacb95..44824e3 100644 --- a/tools/perf/util/bpf-loader.c +++ b/tools/perf/util/bpf-loader.c @@ -17,6 +17,7 @@ #include "llvm-utils.h" #include "probe-event.h" #include "probe-finder.h" // for MAX_PROBES +#include "parse-events.h" #include "llvm-utils.h" #define DEFINE_PRINT_FN(name, level) \ @@ -747,6 +748,7 @@ enum bpf_map_op_type { enum bpf_map_key_type { BPF_MAP_KEY_ALL, + BPF_MAP_KEY_RANGES, }; struct bpf_map_op { @@ -754,6 +756,9 @@ struct bpf_map_op { enum bpf_map_op_type op_type; enum bpf_map_key_type key_type; union { + struct parse_events_array array; + } k; + union { u64 value; struct perf_evsel *evsel; } v; @@ -768,6 +773,8 @@ bpf_map_op__delete(struct bpf_map_op *op) { if (!list_empty(&op->list)) list_del(&op->list); + if (op->key_type == BPF_MAP_KEY_RANGES) + parse_events__clear_array(&op->k.array); free(op); } @@ -792,10 +799,33 @@ bpf_map_priv__clear(struct bpf_map *map __maybe_unused, free(priv); } +static int +bpf_map_op_setkey(struct bpf_map_op *op, struct parse_events_term *term) +{ + op->key_type = BPF_MAP_KEY_ALL; + if (!term) + return 0; + + if (term->array.nr_ranges) { + size_t memsz = term->array.nr_ranges * + sizeof(op->k.array.ranges[0]); + + op->k.array.ranges = memdup(term->array.ranges, memsz); + if (!op->k.array.ranges) { + pr_debug("No enough memory to alloc indices for map\n"); + return -ENOMEM; + } + op->key_type = BPF_MAP_KEY_RANGES; + op->k.array.nr_ranges = term->array.nr_ranges; + } + return 0; +} + static struct bpf_map_op * -bpf_map_op__new(void) +bpf_map_op__new(struct parse_events_term *term) { struct bpf_map_op *op; + int err; op = zalloc(sizeof(*op)); if (!op) { @@ -804,7 +834,11 @@ bpf_map_op__new(void) } INIT_LIST_HEAD(&op->list); - op->key_type = BPF_MAP_KEY_ALL; + err = bpf_map_op_setkey(op, term); + if (err) { + free(op); + return ERR_PTR(err); + } return op; } @@ -841,12 +875,12 @@ bpf_map__add_op(struct bpf_map *map, struct bpf_map_op *op) } static struct bpf_map_op * -bpf_map__add_newop(struct bpf_map *map) +bpf_map__add_newop(struct bpf_map *map, struct parse_events_term *term) { struct bpf_map_op *op; int err; - op = bpf_map_op__new(); + op = bpf_map_op__new(term); if (IS_ERR(op)) return op; @@ -896,7 +930,7 @@ __bpf_map__config_value(struct bpf_map *map, return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE; } - op = bpf_map__add_newop(map); + op = bpf_map__add_newop(map, term); if (IS_ERR(op)) return PTR_ERR(op); op->op_type = BPF_MAP_OP_SET_VALUE; @@ -958,7 +992,7 @@ __bpf_map__config_event(struct bpf_map *map, return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE; } - op = bpf_map__add_newop(map); + op = bpf_map__add_newop(map, term); if (IS_ERR(op)) return PTR_ERR(op); op->op_type = BPF_MAP_OP_SET_EVSEL; @@ -996,6 +1030,44 @@ struct bpf_obj_config__map_func bpf_obj_config__map_funcs[] = { }; static int +config_map_indices_range_check(struct parse_events_term *term, + struct bpf_map *map, + const char *map_name) +{ + struct parse_events_array *array = &term->array; + struct bpf_map_def def; + unsigned int i; + int err; + + if (!array->nr_ranges) + return 0; + if (!array->ranges) { + pr_debug("ERROR: map %s: array->nr_ranges is %d but range array is NULL\n", + map_name, (int)array->nr_ranges); + return -BPF_LOADER_ERRNO__INTERNAL; + } + + err = bpf_map__get_def(map, &def); + if (err) { + pr_debug("ERROR: Unable to get map definition from '%s'\n", + map_name); + return -BPF_LOADER_ERRNO__INTERNAL; + } + + for (i = 0; i < array->nr_ranges; i++) { + unsigned int start = array->ranges[i].start; + size_t length = array->ranges[i].length; + unsigned int idx = start + length - 1; + + if (idx >= def.max_entries) { + pr_debug("ERROR: index %d too large\n", idx); + return -BPF_LOADER_ERRNO__OBJCONF_MAP_IDX2BIG; + } + } + return 0; +} + +static int bpf__obj_config_map(struct bpf_object *obj, struct parse_events_term *term, struct perf_evlist *evlist, @@ -1030,7 +1102,12 @@ bpf__obj_config_map(struct bpf_object *obj, goto out; } - *key_scan_pos += map_opt - map_name; + *key_scan_pos += strlen(map_opt); + err = config_map_indices_range_check(term, map, map_name); + if (err) + goto out; + *key_scan_pos -= strlen(map_opt); + 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]; @@ -1100,6 +1177,33 @@ foreach_key_array_all(map_config_func_t func, } static int +foreach_key_array_ranges(map_config_func_t func, void *arg, + const char *name, int map_fd, + struct bpf_map_def *pdef, + struct bpf_map_op *op) +{ + unsigned int i, j; + int err; + + for (i = 0; i < op->k.array.nr_ranges; i++) { + unsigned int start = op->k.array.ranges[i].start; + size_t length = op->k.array.ranges[i].length; + + for (j = 0; j < length; j++) { + unsigned int idx = start + j; + + err = func(name, map_fd, pdef, op, &idx, arg); + if (err) { + pr_debug("ERROR: failed to insert value to %s[%u]\n", + name, idx); + return err; + } + } + } + return 0; +} + +static int bpf_map_config_foreach_key(struct bpf_map *map, map_config_func_t func, void *arg) @@ -1141,14 +1245,19 @@ bpf_map_config_foreach_key(struct bpf_map *map, case BPF_MAP_KEY_ALL: err = foreach_key_array_all(func, arg, name, map_fd, &def, op); - if (err) - return err; + break; + case BPF_MAP_KEY_RANGES: + err = foreach_key_array_ranges(func, arg, name, + map_fd, &def, + op); break; default: pr_debug("ERROR: keytype for map '%s' invalid\n", name); return -BPF_LOADER_ERRNO__INTERNAL; } + if (err) + return err; break; default: pr_debug("ERROR: type of '%s' incorrect\n", name); @@ -1336,6 +1445,7 @@ static const char *bpf_loader_strerror_table[NR_ERRNO] = { [ERRCODE_OFFSET(OBJCONF_MAP_EVTDIM)] = "Event dimension too large", [ERRCODE_OFFSET(OBJCONF_MAP_EVTINH)] = "Doesn't support inherit event", [ERRCODE_OFFSET(OBJCONF_MAP_EVTTYPE)] = "Wrong event type for map", + [ERRCODE_OFFSET(OBJCONF_MAP_IDX2BIG)] = "Index too large", }; static int diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h index 7c7689f..be43119 100644 --- a/tools/perf/util/bpf-loader.h +++ b/tools/perf/util/bpf-loader.h @@ -38,6 +38,7 @@ enum bpf_loader_errno { BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM, /* Event dimension too large */ BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH, /* Doesn't support inherit event */ BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE, /* Wrong event type for map */ + BPF_LOADER_ERRNO__OBJCONF_MAP_IDX2BIG, /* Index too large */ __BPF_LOADER_ERRNO__END, }; diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index 5909fd2..697d350 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -2211,6 +2211,8 @@ void parse_events_terms__purge(struct list_head *terms) struct parse_events_term *term, *h; list_for_each_entry_safe(term, h, terms, list) { + if (term->array.nr_ranges) + free(term->array.ranges); list_del_init(&term->list); free(term); } @@ -2224,6 +2226,11 @@ void parse_events_terms__delete(struct list_head *terms) free(terms); } +void parse_events__clear_array(struct parse_events_array *a) +{ + free(a->ranges); +} + void parse_events_evlist_error(struct parse_events_evlist *data, int idx, const char *str) { diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h index e036969..e445622 100644 --- a/tools/perf/util/parse-events.h +++ b/tools/perf/util/parse-events.h @@ -72,8 +72,17 @@ enum { __PARSE_EVENTS__TERM_TYPE_NR, }; +struct parse_events_array { + size_t nr_ranges; + struct { + unsigned int start; + size_t length; + } *ranges; +}; + struct parse_events_term { char *config; + struct parse_events_array array; union { char *str; u64 num; @@ -120,6 +129,7 @@ int parse_events_term__clone(struct parse_events_term **new, struct parse_events_term *term); void parse_events_terms__delete(struct list_head *terms); void parse_events_terms__purge(struct list_head *terms); +void parse_events__clear_array(struct parse_events_array *a); int parse_events__modifier_event(struct list_head *list, char *str, bool add); int parse_events__modifier_group(struct list_head *list, char *event_mod); int parse_events_name(struct list_head *list, char *name); -- 2.7.4