[PATCH 03/31] perf tools: Enable passing bpf object file to --event
From: Wang Nan
Date: Wed Oct 14 2015 - 08:50:53 EST
By introducing new rules in tools/perf/util/parse-events.[ly], this
patch enables 'perf record --event bpf_file.o' to select events by an
eBPF object file. It calls parse_events_load_bpf() to load that file,
which uses bpf__prepare_load() and finally calls bpf_object__open() for
the object files.
After applying this patch, commands like:
# perf record --event foo.o sleep
become possible.
However, at this point it is unable to link any useful things onto the
evsel list because the creating of probe points and BPF program
attaching have not been implemented. Before real events are possible to
be extracted, to avoid perf report error because of empty evsel list,
this patch link a dummy evsel. The dummy event related code will be
removed when probing and extracting code is ready.
Signed-off-by: Wang Nan <wangnan0@xxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Brendan Gregg <brendan.d.gregg@xxxxxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: He Kuang <hekuang@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kaixu Xia <xiakaixu@xxxxxxxxxx>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Zefan Li <lizefan@xxxxxxxxxx>
Cc: pi3orama@xxxxxxx
Link: http://lkml.kernel.org/n/ebpf-6yw9eg0ej3l4jnqhinngkw86@xxxxxxxxxxxxxx
---
tools/perf/perf.c | 2 ++
tools/perf/util/Build | 1 +
tools/perf/util/parse-events.c | 57 ++++++++++++++++++++++++++++++++++++++++++
tools/perf/util/parse-events.h | 8 ++++++
tools/perf/util/parse-events.l | 3 +++
tools/perf/util/parse-events.y | 18 ++++++++++++-
6 files changed, 88 insertions(+), 1 deletion(-)
diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index 5437134..3d4c7c0 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -15,6 +15,7 @@
#include "util/run-command.h"
#include "util/parse-events.h"
#include "util/parse-options.h"
+#include "util/bpf-loader.h"
#include "util/debug.h"
#include <api/fs/tracing_path.h>
#include <pthread.h>
@@ -385,6 +386,7 @@ static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
status = p->fn(argc, argv, prefix);
exit_browser(status);
perf_env__exit(&perf_env);
+ bpf__clear();
if (status)
return status & 0xff;
diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index 9217119..591b3fe 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -87,6 +87,7 @@ libperf-$(CONFIG_AUXTRACE) += intel-bts.o
libperf-y += parse-branch-options.o
libperf-y += parse-regs-options.o
+libperf-$(CONFIG_LIBBPF) += bpf-loader.o
libperf-$(CONFIG_LIBELF) += symbol-elf.o
libperf-$(CONFIG_LIBELF) += probe-file.o
libperf-$(CONFIG_LIBELF) += probe-event.o
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 991bbd4..a02abd3 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -11,6 +11,7 @@
#include "symbol.h"
#include "cache.h"
#include "header.h"
+#include "bpf-loader.h"
#include "debug.h"
#include <api/fs/tracing_path.h>
#include "parse-events-bison.h"
@@ -529,6 +530,62 @@ static int add_tracepoint_multi_sys(struct list_head *list, int *idx,
return ret;
}
+int parse_events_load_bpf_obj(struct parse_events_evlist *data,
+ struct list_head *list,
+ struct bpf_object *obj)
+{
+ int err;
+ char errbuf[BUFSIZ];
+
+ if (IS_ERR(obj) || !obj) {
+ snprintf(errbuf, sizeof(errbuf),
+ "Internal error: load bpf obj with NULL");
+ err = -EINVAL;
+ goto errout;
+ }
+
+ /*
+ * Temporary add a dummy event here so we can check whether
+ * basic bpf loader works. Following patches will replace
+ * dummy event by useful evsels.
+ */
+ return parse_events_add_numeric(data, list, PERF_TYPE_SOFTWARE,
+ PERF_COUNT_SW_DUMMY, NULL);
+errout:
+ data->error->help = strdup("(add -v to see detail)");
+ data->error->str = strdup(errbuf);
+ return err;
+}
+
+int parse_events_load_bpf(struct parse_events_evlist *data,
+ struct list_head *list,
+ char *bpf_file_name)
+{
+ struct bpf_object *obj;
+
+ obj = bpf__prepare_load(bpf_file_name);
+ if (IS_ERR(obj) || !obj) {
+ char errbuf[BUFSIZ];
+ int err;
+
+ err = obj ? PTR_ERR(obj) : -EINVAL;
+
+ if (err == -ENOTSUP)
+ snprintf(errbuf, sizeof(errbuf),
+ "BPF support is not compiled");
+ else
+ snprintf(errbuf, sizeof(errbuf),
+ "BPF object file '%s' is invalid",
+ bpf_file_name);
+
+ data->error->help = strdup("(add -v to see detail)");
+ data->error->str = strdup(errbuf);
+ return err;
+ }
+
+ return parse_events_load_bpf_obj(data, list, obj);
+}
+
static int
parse_breakpoint_type(const char *type, struct perf_event_attr *attr)
{
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index f13d3cc..fbb16c7 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -121,6 +121,14 @@ int parse_events_add_tracepoint(struct list_head *list, int *idx,
char *sys, char *event,
struct parse_events_error *error,
struct list_head *head_config);
+int parse_events_load_bpf(struct parse_events_evlist *data,
+ struct list_head *list,
+ char *bpf_file_name);
+/* Provide this function for perf test */
+struct bpf_object;
+int parse_events_load_bpf_obj(struct parse_events_evlist *data,
+ struct list_head *list,
+ struct bpf_object *obj);
int parse_events_add_numeric(struct parse_events_evlist *data,
struct list_head *list,
u32 type, u64 config,
diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index be24457..5e5d31a 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -115,6 +115,7 @@ do { \
group [^,{}/]*[{][^}]*[}][^,{}/]*
event_pmu [^,{}/]+[/][^/]*[/][^,{}/]*
event [^,{}/]+
+bpf_object .*\.(o|bpf)
num_dec [0-9]+
num_hex 0x[a-fA-F0-9]+
@@ -159,6 +160,7 @@ modifier_bp [rwx]{1,3}
}
{event_pmu} |
+{bpf_object} |
{event} {
BEGIN(INITIAL);
REWIND(1);
@@ -264,6 +266,7 @@ r{num_raw_hex} { return raw(yyscanner); }
{num_hex} { return value(yyscanner, 16); }
{modifier_event} { return str(yyscanner, PE_MODIFIER_EVENT); }
+{bpf_object} { return str(yyscanner, PE_BPF_OBJECT); }
{name} { return pmu_str_check(yyscanner); }
"/" { BEGIN(config); return '/'; }
- { return '-'; }
diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index ae6af26..497f19b 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -42,6 +42,7 @@ static inc_group_count(struct list_head *list,
%token PE_VALUE PE_VALUE_SYM_HW PE_VALUE_SYM_SW PE_RAW PE_TERM
%token PE_EVENT_NAME
%token PE_NAME
+%token PE_BPF_OBJECT
%token PE_MODIFIER_EVENT PE_MODIFIER_BP
%token PE_NAME_CACHE_TYPE PE_NAME_CACHE_OP_RESULT
%token PE_PREFIX_MEM PE_PREFIX_RAW PE_PREFIX_GROUP
@@ -53,6 +54,7 @@ static inc_group_count(struct list_head *list,
%type <num> PE_RAW
%type <num> PE_TERM
%type <str> PE_NAME
+%type <str> PE_BPF_OBJECT
%type <str> PE_NAME_CACHE_TYPE
%type <str> PE_NAME_CACHE_OP_RESULT
%type <str> PE_MODIFIER_EVENT
@@ -70,6 +72,7 @@ static inc_group_count(struct list_head *list,
%type <tracepoint_name> tracepoint_name
%type <head> event_legacy_numeric
%type <head> event_legacy_raw
+%type <head> event_bpf_file
%type <head> event_def
%type <head> event_mod
%type <head> event_name
@@ -203,7 +206,8 @@ event_def: event_pmu |
event_legacy_mem |
event_legacy_tracepoint sep_dc |
event_legacy_numeric sep_dc |
- event_legacy_raw sep_dc
+ event_legacy_raw sep_dc |
+ event_bpf_file
event_pmu:
PE_NAME '/' event_config '/'
@@ -449,6 +453,18 @@ PE_RAW
$$ = list;
}
+event_bpf_file:
+PE_BPF_OBJECT
+{
+ struct parse_events_evlist *data = _data;
+ struct parse_events_error *error = data->error;
+ struct list_head *list;
+
+ ALLOC_LIST(list);
+ ABORT_ON(parse_events_load_bpf(data, list, $1));
+ $$ = list;
+}
+
start_terms: event_config
{
struct parse_events_terms *data = _data;
--
1.8.3.4
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