[tip:perf/core] perf tools: Support setting different slots in a BPF map separately
From: tip-bot for Wang Nan
Date: Thu Feb 25 2016 - 01:28:41 EST
Commit-ID: 2d055bf253c0d606c5de3fe7749e3188080780ad
Gitweb: http://git.kernel.org/tip/2d055bf253c0d606c5de3fe7749e3188080780ad
Author: Wang Nan <wangnan0@xxxxxxxxxx>
AuthorDate: Mon, 22 Feb 2016 09:10:34 +0000
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Mon, 22 Feb 2016 12:48:50 -0300
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 <wangnan0@xxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxxxxxx>
Cc: Brendan Gregg <brendan.d.gregg@xxxxxxxxx>
Cc: Cody P Schafer <dev@xxxxxxxxxx>
Cc: He Kuang <hekuang@xxxxxxxxxx>
Cc: Jeremie Galarneau <jeremie.galarneau@xxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kirill Smelkov <kirr@xxxxxxxxxx>
Cc: Li Zefan <lizefan@xxxxxxxxxx>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Zefan Li <lizefan@xxxxxxxxxx>
Cc: pi3orama@xxxxxxx
Link: http://lkml.kernel.org/r/1456132275-98875-8-git-send-email-wangnan0@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
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);