perf tools: Apply tracepoint event definition options to BPF script

Users can pass options to tracepoints defined in the BPF script.  For
example:

  # perf record -e ./test.c/no-inherit/ bash
  # dd if=/dev/zero of=/dev/null count=10000
  # exit
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.022 MB perf.data (139 samples) ]

  (no-inherit works, only the sys_read issued by bash are captured, at
   least 10000 sys_read issued by dd are skipped.)

test.c:

  #define SEC(NAME) __attribute__((section(NAME), used))
  SEC("func=sys_read")
  int bpf_func__sys_read(void *ctx)
  {
      return 1;
  }
  char _license[] SEC("license") = "GPL";
  int _version SEC("version") = LINUX_VERSION_CODE;

no-inherit is applied to the kprobe event defined in test.c.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Cody P Schafer <dev@codyps.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jeremie Galarneau <jeremie.galarneau@efficios.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kirill Smelkov <kirr@nexedi.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1456132275-98875-10-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
index 4aed5cb..199501c 100644 (file)
--- a/tools/perf/tests/bpf.c
+++ b/tools/perf/tests/bpf.c
@@ -112,7 +112,7 @@ static int do_test(struct bpf_object *obj, int (*func)(void),
        parse_evlist.error = &parse_error;
        INIT_LIST_HEAD(&parse_evlist.list);
 
-       err = parse_events_load_bpf_obj(&parse_evlist, &parse_evlist.list, obj);
+       err = parse_events_load_bpf_obj(&parse_evlist, &parse_evlist.list, obj, NULL);
        if (err || list_empty(&parse_evlist.list)) {
                pr_debug("Failed to add events selected by BPF\n");
                return TEST_FAIL;

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 6e2f203..4c19d5e 100644 (file)
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -581,6 +581,7 @@ static int add_tracepoint_multi_sys(struct list_head *list, int *idx,
 struct __add_bpf_event_param {
        struct parse_events_evlist *data;
        struct list_head *list;
+       struct list_head *head_config;
 };
 
 static int add_bpf_event(struct probe_trace_event *tev, int fd,
@@ -597,7 +598,8 @@ static int add_bpf_event(struct probe_trace_event *tev, int fd,
                 tev->group, tev->event, fd);
 
        err = parse_events_add_tracepoint(&new_evsels, &evlist->idx, tev->group,
-                                         tev->event, evlist->error, NULL);
+                                         tev->event, evlist->error,
+                                         param->head_config);
        if (err) {
                struct perf_evsel *evsel, *tmp;
 
@@ -622,11 +624,12 @@ static int add_bpf_event(struct probe_trace_event *tev, int fd,
 
 int parse_events_load_bpf_obj(struct parse_events_evlist *data,
                              struct list_head *list,
-                             struct bpf_object *obj)
+                             struct bpf_object *obj,
+                             struct list_head *head_config)
 {
        int err;
        char errbuf[BUFSIZ];
-       struct __add_bpf_event_param param = {data, list};
+       struct __add_bpf_event_param param = {data, list, head_config};
        static bool registered_unprobe_atexit = false;
 
        if (IS_ERR(obj) || !obj) {
@@ -720,14 +723,47 @@ parse_events_config_bpf(struct parse_events_evlist *data,
        return 0;
 }
 
+/*
+ * Split config terms:
+ * perf record -e bpf.c/call-graph=fp,map:array.value[0]=1/ ...
+ *  'call-graph=fp' is 'evt config', should be applied to each
+ *  events in bpf.c.
+ * 'map:array.value[0]=1' is 'obj config', should be processed
+ * with parse_events_config_bpf.
+ *
+ * Move object config terms from the first list to obj_head_config.
+ */
+static void
+split_bpf_config_terms(struct list_head *evt_head_config,
+                      struct list_head *obj_head_config)
+{
+       struct parse_events_term *term, *temp;
+
+       /*
+        * Currectly, all possible user config term
+        * belong to bpf object. parse_events__is_hardcoded_term()
+        * happends to be a good flag.
+        *
+        * See parse_events_config_bpf() and
+        * config_term_tracepoint().
+        */
+       list_for_each_entry_safe(term, temp, evt_head_config, list)
+               if (!parse_events__is_hardcoded_term(term))
+                       list_move_tail(&term->list, obj_head_config);
+}
+
 int parse_events_load_bpf(struct parse_events_evlist *data,
                          struct list_head *list,
                          char *bpf_file_name,
                          bool source,
                          struct list_head *head_config)
 {
-       struct bpf_object *obj;
        int err;
+       struct bpf_object *obj;
+       LIST_HEAD(obj_head_config);
+
+       if (head_config)
+               split_bpf_config_terms(head_config, &obj_head_config);
 
        obj = bpf__prepare_load(bpf_file_name, source);
        if (IS_ERR(obj)) {
@@ -749,10 +785,18 @@ int parse_events_load_bpf(struct parse_events_evlist *data,
                return err;
        }
 
-       err = parse_events_load_bpf_obj(data, list, obj);
+       err = parse_events_load_bpf_obj(data, list, obj, head_config);
        if (err)
                return err;
-       return parse_events_config_bpf(data, obj, head_config);
+       err = parse_events_config_bpf(data, obj, &obj_head_config);
+
+       /*
+        * Caller doesn't know anything about obj_head_config,
+        * so combine them together again before returnning.
+        */
+       if (head_config)
+               list_splice_tail(&obj_head_config, head_config);
+       return err;
 }
 
 static int

diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index e445622..67e4930 100644 (file)
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -146,7 +146,8 @@ int parse_events_load_bpf(struct parse_events_evlist *data,
 struct bpf_object;
 int parse_events_load_bpf_obj(struct parse_events_evlist *data,
                              struct list_head *list,
-                             struct bpf_object *obj);
+                             struct bpf_object *obj,
+                             struct list_head *head_config);
 int parse_events_add_numeric(struct parse_events_evlist *data,
                             struct list_head *list,
                             u32 type, u64 config,