perf probe: Enable to put probe inline function call site

Enable to put probe inline function call site. This will increase line-based
probe-ability.

<Without this patch>
$ ./perf probe -L schedule:48
<schedule:48>
                pre_schedule(rq, prev);

     50         if (unlikely(!rq->nr_running))
                        idle_balance(cpu, rq);

                put_prev_task(rq, prev);
                next = pick_next_task(rq);

     56         if (likely(prev != next)) {
                        sched_info_switch(prev, next);
                        trace_sched_switch_out(prev, next);
                        perf_event_task_sched_out(prev, next);

<With this patch>
$ ./perf probe -L schedule:48
<schedule:48>
     48         pre_schedule(rq, prev);

     50         if (unlikely(!rq->nr_running))
     51                 idle_balance(cpu, rq);

     53         put_prev_task(rq, prev);
     54         next = pick_next_task(rq);

     56         if (likely(prev != next)) {
     57                 sched_info_switch(prev, next);
     58                 trace_sched_switch_out(prev, next);
     59                 perf_event_task_sched_out(prev, next);

Cc: 2nddept-manager@sdl.hitachi.co.jp
Cc: Franck Bui-Huu <fbuihuu@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20110113124604.22426.48873.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 508c017f566acf7e0576513abb50117e40ad8fdb..69215bff17e91354e81bf1267cf15c085bdb5079 100644 (file)
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -280,6 +280,19 @@ static bool die_compare_name(Dwarf_Die *dw_die, const char *tname)
        return name ? (strcmp(tname, name) == 0) : false;
 }
 
+/* Get callsite line number of inline-function instance */
+static int die_get_call_lineno(Dwarf_Die *in_die)
+{
+       Dwarf_Attribute attr;
+       Dwarf_Word ret;
+
+       if (!dwarf_attr(in_die, DW_AT_call_line, &attr))
+               return -ENOENT;
+
+       dwarf_formudata(&attr, &ret);
+       return (int)ret;
+}
+
 /* Get type die */
 static Dwarf_Die *die_get_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
 {
@@ -463,27 +476,54 @@ typedef int (* line_walk_handler_t) (const char *fname, int lineno,
                                     Dwarf_Addr addr, void *data);
 
 struct __line_walk_param {
+       const char *fname;
        line_walk_handler_t handler;
        void *data;
        int retval;
 };
 
-/* Walk on decl lines in given DIE */
+static int __die_walk_funclines_cb(Dwarf_Die *in_die, void *data)
+{
+       struct __line_walk_param *lw = data;
+       Dwarf_Addr addr;
+       int lineno;
+
+       if (dwarf_tag(in_die) == DW_TAG_inlined_subroutine) {
+               lineno = die_get_call_lineno(in_die);
+               if (lineno > 0 && dwarf_entrypc(in_die, &addr) == 0) {
+                       lw->retval = lw->handler(lw->fname, lineno, addr,
+                                                lw->data);
+                       if (lw->retval != 0)
+                               return DIE_FIND_CB_FOUND;
+               }
+       }
+       return DIE_FIND_CB_SIBLING;
+}
+
+/* Walk on lines of blocks included in given DIE */
 static int __die_walk_funclines(Dwarf_Die *sp_die,
                                line_walk_handler_t handler, void *data)
 {
-       const char *fname;
+       struct __line_walk_param lw = {
+               .handler = handler,
+               .data = data,
+               .retval = 0,
+       };
+       Dwarf_Die die_mem;
        Dwarf_Addr addr;
-       int lineno, ret = 0;
+       int lineno;
 
        /* Handle function declaration line */
-       fname = dwarf_decl_file(sp_die);
-       if (fname && dwarf_decl_line(sp_die, &lineno) == 0 &&
+       lw.fname = dwarf_decl_file(sp_die);
+       if (lw.fname && dwarf_decl_line(sp_die, &lineno) == 0 &&
            dwarf_entrypc(sp_die, &addr) == 0) {
-               ret = handler(fname, lineno, addr, data);
+               lw.retval = handler(lw.fname, lineno, addr, data);
+               if (lw.retval != 0)
+                       goto done;
        }
-
-       return ret;
+       die_find_child(sp_die, __die_walk_funclines_cb, &lw, &die_mem);
+done:
+       return lw.retval;
 }
 
 static int __die_walk_culines_cb(Dwarf_Die *sp_die, void *data)