This patch adds the final step for BPF map configuration. A new syntax
is appended into parser so user can config BPF objects through '/' '/'
enclosed config terms.
After this patch, BPF programs for perf are finally able to utilize
bpf_perf_event_read() introduced in commit 35578d7984003097af2b1e3
(bpf: Implement function bpf_perf_event_read() that get the selected
hardware PMU conuter) by following way:
===== BPF program bpf_program.c =====
struct bpf_map_def SEC("maps") pmu_map = {
.type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(u32),
.max_entries = __NR_CPUS__,
};
SEC("func_write=sys_write")
int func_write(void *ctx)
{
unsigned long long val;
char fmt[] = "sys_write: pmu=%llu\n";
val = bpf_perf_event_read(&pmu_map, bpf_get_smp_processor_id());
bpf_trace_printk(fmt, sizeof(fmt), val);
return 0;
}
SEC("func_write_return=sys_write%return")
int func_write_return(void *ctx)
{
unsigned long long val = 0;
char fmt[] = "sys_write_return: pmu=%llu\n";
val = bpf_perf_event_read(&pmu_map, bpf_get_smp_processor_id());
bpf_trace_printk(fmt, sizeof(fmt), val);
return 0;
}
===== cmdline =====
# echo "" > /sys/kernel/debug/tracing/trace
# perf record -e evt=cycles/period=0x7fffffffffffffff/ \
-e bpf_program.c/maps.pmu_map.event=evt/
-a ls
# cat /sys/kernel/debug/tracing/trace | grep ls
ls-3363 [003] d... 75475.056190: : sys_write: pmu=3961415
ls-3363 [003] dN.. 75475.056212: : sys_write_return: pmu=4051390
ls-3363 [003] d... 75475.056216: : sys_write: pmu=4065447
ls-3363 [003] dN.. 75475.056227: : sys_write_return: pmu=4109760
ls-3363 [003] d... 75475.056230: : sys_write: pmu=4120776
ls-3363 [003] dN.. 75475.056245: : sys_write_return: pmu=4178441
...
# perf report --stdio
Error:
The perf.data file has no samples!
Where, setting period of cycles Set a very large value to period
of cycles event because we want to use this event as a counter
only, don't need sampling.
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-2mjd96mowgzslkj8jrwbn...@git.kernel.org
---
tools/perf/util/parse-events.c | 71 ++++++++++++++++++++++++++++++++++++++++--
tools/perf/util/parse-events.h | 3 +-
tools/perf/util/parse-events.y | 19 ++++++++---
3 files changed, 85 insertions(+), 8 deletions(-)
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 06ba5a6..f8b2bb8 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -624,17 +624,79 @@ errout:
return err;
}
+static int
+parse_events_config_bpf(struct parse_events_evlist *data,
+ struct bpf_object *obj,
+ struct list_head *head_config)
+{
+ struct parse_events_term *term;
+
+ if (!head_config || list_empty(head_config))
+ return 0;
+
+ list_for_each_entry(term, head_config, list) {
+ struct bpf_config_val val;
+ char errbuf[BUFSIZ];
+ int err;
+
+ if (term->type_term != PARSE_EVENTS__TERM_TYPE_USER) {
+ snprintf(errbuf, sizeof(errbuf),
+ "Invalid config term for BPF object");
+ errbuf[BUFSIZ - 1] = '\0';
+
+ data->error->idx = term->err_term;
+ data->error->str = strdup(errbuf);
+ return -EINVAL;
+ }
+
+ switch (term->type_val) {
+ case PARSE_EVENTS__TERM_TYPE_NUM:
+ val.type = BPF_CONFIG_VAL_NUM;
+ val.num = (unsigned long long)term->val.num;
+ break;
+ case PARSE_EVENTS__TERM_TYPE_STR:
+ val.type = BPF_CONFIG_VAL_STRING;
+ val.string = term->val.str;
+ break;
+ default:
+ data->error->idx = term->err_val;
+ data->error->str = strdup("Invalid config value");
+ return -EINVAL;
+ }
+
+ err = bpf__config_obj(obj, term->config, &val, data->evlist);
+ if (err) {
+ bpf__strerror_config_obj(obj, term->config, &val,
+ data->evlist, err, errbuf,
+ sizeof(errbuf));
+ data->error->help = strdup(
+"Hint:\tValid config term:\n"
+" \tmaps.<mapname>.event\n"
+" \t(add -v to see detail)");
+ data->error->str = strdup(errbuf);
+ if (err == -EINVAL)
+ data->error->idx = term->err_val;
+ else
+ data->error->idx = term->err_term;
+ return err;
+ }
+ }
+ return 0;
+
+}
+
int parse_events_load_bpf(struct parse_events_evlist *data,
struct list_head *list,
char *bpf_file_name,
- bool source)
+ bool source,
+ struct list_head *head_config)
{
struct bpf_object *obj;
+ int err;
obj = bpf__prepare_load(bpf_file_name, source);
if (IS_ERR(obj) || !obj) {
char errbuf[BUFSIZ];
- int err;
err = obj ? PTR_ERR(obj) : -EINVAL;
@@ -651,7 +713,10 @@ int parse_events_load_bpf(struct parse_events_evlist *data,
return err;
}
- return parse_events_load_bpf_obj(data, list, obj);
+ err = parse_events_load_bpf_obj(data, list, obj);
+ if (err)
+ return err;
+ return parse_events_config_bpf(data, obj, head_config);
}
static int
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index b525353..d4aa88e 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -125,7 +125,8 @@ int parse_events_add_tracepoint(struct list_head *list, int
*idx,
int parse_events_load_bpf(struct parse_events_evlist *data,
struct list_head *list,
char *bpf_file_name,
- bool source);
+ bool source,
+ struct list_head *head_config);
/* Provide this function for perf test */
struct bpf_object;
int parse_events_load_bpf_obj(struct parse_events_evlist *data,
diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index 90e382f..545bce5 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -64,6 +64,7 @@ static inc_group_count(struct list_head *list,
%type <str> PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_KERNEL_PMU_EVENT
%type <num> value_sym
%type <head> event_config
+%type <head> event_bpf_config
%type <term> event_term
%type <head> event_pmu
%type <head> event_legacy_symbol
@@ -468,27 +469,37 @@ PE_RAW
}
event_bpf_file:
-PE_BPF_OBJECT
+PE_BPF_OBJECT event_bpf_config
{
struct parse_events_evlist *data = _data;
struct parse_events_error *error = data->error;
struct list_head *list;
ALLOC_LIST(list);
- ABORT_ON(parse_events_load_bpf(data, list, $1, false));
+ ABORT_ON(parse_events_load_bpf(data, list, $1, false, $2));
$$ = list;
}
|
-PE_BPF_SOURCE
+PE_BPF_SOURCE event_bpf_config
{
struct parse_events_evlist *data = _data;
struct list_head *list;
ALLOC_LIST(list);
- ABORT_ON(parse_events_load_bpf(data, list, $1, true));
+ ABORT_ON(parse_events_load_bpf(data, list, $1, true, $2));
$$ = list;
}
+event_bpf_config:
+'/' event_config '/'
+{
+ $$ = $2;
+}
+|
+{
+ $$ = NULL;
+}
+
start_terms: event_config
{
struct parse_events_terms *data = _data;
--
1.8.3.4
--
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