perf probe: Check function address range strictly in line finder

Check (inlined) function address range strictly for
improving output of probe-able lines of inline functions.

Without this change, perf probe --line <function> sometimes
showed other inline function bodies too, because it didn't
filter out inlined functions.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
LKML-Reference: <20100225133557.6725.20697.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 53 insertions, 21 deletions

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 6305f344f382..a41035634dd8 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -161,6 +161,31 @@ static Dwarf_Die *die_get_real_subprogram(Dwarf_Die *cu_die, Dwarf_Addr addr,
                 return die_mem;
 }
 
+/* Similar to dwarf_getfuncs, but returns inlined_subroutine if exists. */
+static Dwarf_Die *die_get_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
+                                     Dwarf_Die *die_mem)
+{
+        Dwarf_Die child_die;
+        int ret;
+
+        ret = dwarf_child(sp_die, die_mem);
+        if (ret != 0)
+                return NULL;
+
+        do {
+                if (dwarf_tag(die_mem) == DW_TAG_inlined_subroutine &&
+                    dwarf_haspc(die_mem, addr))
+                        return die_mem;
+
+                if (die_get_inlinefunc(die_mem, addr, &child_die)) {
+                        memcpy(die_mem, &child_die, sizeof(Dwarf_Die));
+                        return die_mem;
+                }
+        } while (dwarf_siblingof(die_mem, die_mem) == 0);
+
+        return NULL;
+}
+
 /* Compare diename and tname */
 static bool die_compare_name(Dwarf_Die *dw_die, const char *tname)
 {
@@ -534,7 +559,7 @@ found:
 }
 
 /* Find line range from its line number */
-static void find_line_range_by_line(struct line_finder *lf)
+static void find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
 {
         Dwarf_Lines *lines;
         Dwarf_Line *line;
@@ -543,6 +568,7 @@ static void find_line_range_by_line(struct line_finder *lf)
         int lineno;
         int ret;
         const char *src;
+        Dwarf_Die die_mem;
 
         INIT_LIST_HEAD(&lf->lr->line_list);
         ret = dwarf_getsrclines(&lf->cu_die, &lines, &nlines);
@@ -550,22 +576,28 @@ static void find_line_range_by_line(struct line_finder *lf)
 
         for (i = 0; i < nlines; i++) {
                 line = dwarf_onesrcline(lines, i);
-                dwarf_lineno(line, &lineno);
+                ret = dwarf_lineno(line, &lineno);
+                DIE_IF(ret != 0);
                 if (lf->lno_s > lineno || lf->lno_e < lineno)
                         continue;
 
+                if (sp_die) {
+                        /* Address filtering 1: does sp_die include addr? */
+                        ret = dwarf_lineaddr(line, &addr);
+                        DIE_IF(ret != 0);
+                        if (!dwarf_haspc(sp_die, addr))
+                                continue;
+
+                        /* Address filtering 2: No child include addr? */
+                        if (die_get_inlinefunc(sp_die, addr, &die_mem))
+                                continue;
+                }
+
                 /* TODO: Get fileno from line, but how? */
                 src = dwarf_linesrc(line, NULL, NULL);
                 if (strtailcmp(src, lf->fname) != 0)
                         continue;
 
-                /* Filter line in the function address range */
-                if (lf->addr_s && lf->addr_e) {
-                        ret = dwarf_lineaddr(line, &addr);
-                        DIE_IF(ret != 0);
-                        if (lf->addr_s > addr || lf->addr_e <= addr)
-                                continue;
-                }
                 /* Copy real path */
                 if (!lf->lr->path)
                         lf->lr->path = strdup(src);
@@ -580,24 +612,20 @@ static void find_line_range_by_line(struct line_finder *lf)
         }
 }
 
+static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
+{
+        find_line_range_by_line(in_die, (struct line_finder *)data);
+        return DWARF_CB_ABORT;  /* No need to find other instances */
+}
+
 /* Search function from function name */
 static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
 {
         struct line_finder *lf = (struct line_finder *)data;
         struct line_range *lr = lf->lr;
-        int ret;
 
         if (dwarf_tag(sp_die) == DW_TAG_subprogram &&
             die_compare_name(sp_die, lr->function) == 0) {
-                /* Get the address range of this function */
-                ret = dwarf_highpc(sp_die, &lf->addr_e);
-                if (ret == 0)
-                        ret = dwarf_lowpc(sp_die, &lf->addr_s);
-                if (ret != 0) {
-                        lf->addr_s = 0;
-                        lf->addr_e = 0;
-                }
-
                 lf->fname = dwarf_decl_file(sp_die);
                 dwarf_decl_line(sp_die, &lr->offset);
                 pr_debug("fname: %s, lineno:%d\n", lf->fname, lr->offset);
@@ -608,7 +636,11 @@ static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
                         lf->lno_e = lr->offset + lr->end;
                 lr->start = lf->lno_s;
                 lr->end = lf->lno_e;
-                find_line_range_by_line(lf);
+                if (dwarf_func_inline(sp_die))
+                        dwarf_func_inline_instances(sp_die,
+                                                    line_range_inline_cb, lf);
+                else
+                        find_line_range_by_line(sp_die, lf);
                 return 1;
         }
         return 0;
@@ -660,7 +692,7 @@ int find_line_range(int fd, struct line_range *lr)
                                         lf.lno_e = INT_MAX;
                                 else
                                         lf.lno_e = lr->end;
-                                find_line_range_by_line(&lf);
+                                find_line_range_by_line(NULL, &lf);
                         }
                 }
                 off = noff;