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>

1 files changed, 48 insertions, 8 deletions

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 508c017f566a..69215bff17e9 100644
--- 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)