perf probe: Introduce lines walker interface

Introduce die_walk_lines() for walking on the line list of given die, and use
it in line_range finder and probe point finder.

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: <20110113124558.22426.48170.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
[ committer note: s/%ld/%zd/ for a size_t nlines var that broke f14 x86 build]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 167 insertions, 154 deletions

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index ab83b6ac5d65..508c017f566a 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -458,6 +458,124 @@ static Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
         return die_find_child(sp_die, __die_find_inline_cb, &addr, die_mem);
 }
 
+/* Walker on lines (Note: line number will not be sorted) */
+typedef int (* line_walk_handler_t) (const char *fname, int lineno,
+                                     Dwarf_Addr addr, void *data);
+
+struct __line_walk_param {
+        line_walk_handler_t handler;
+        void *data;
+        int retval;
+};
+
+/* Walk on decl lines in given DIE */
+static int __die_walk_funclines(Dwarf_Die *sp_die,
+                                line_walk_handler_t handler, void *data)
+{
+        const char *fname;
+        Dwarf_Addr addr;
+        int lineno, ret = 0;
+
+        /* Handle function declaration line */
+        fname = dwarf_decl_file(sp_die);
+        if (fname && dwarf_decl_line(sp_die, &lineno) == 0 &&
+            dwarf_entrypc(sp_die, &addr) == 0) {
+                ret = handler(fname, lineno, addr, data);
+        }
+
+        return ret;
+}
+
+static int __die_walk_culines_cb(Dwarf_Die *sp_die, void *data)
+{
+        struct __line_walk_param *lw = data;
+
+        lw->retval = __die_walk_funclines(sp_die, lw->handler, lw->data);
+        if (lw->retval != 0)
+                return DWARF_CB_ABORT;
+
+        return DWARF_CB_OK;
+}
+
+/*
+ * Walk on lines inside given PDIE. If the PDIE is subprogram, walk only on
+ * the lines inside the subprogram, otherwise PDIE must be a CU DIE.
+ */
+static int die_walk_lines(Dwarf_Die *pdie, line_walk_handler_t handler,
+                          void *data)
+{
+        Dwarf_Lines *lines;
+        Dwarf_Line *line;
+        Dwarf_Addr addr;
+        const char *fname;
+        int lineno, ret = 0;
+        Dwarf_Die die_mem, *cu_die;
+        size_t nlines, i;
+
+        /* Get the CU die */
+        if (dwarf_tag(pdie) == DW_TAG_subprogram)
+                cu_die = dwarf_diecu(pdie, &die_mem, NULL, NULL);
+        else
+                cu_die = pdie;
+        if (!cu_die) {
+                pr_debug2("Failed to get CU from subprogram\n");
+                return -EINVAL;
+        }
+
+        /* Get lines list in the CU */
+        if (dwarf_getsrclines(cu_die, &lines, &nlines) != 0) {
+                pr_debug2("Failed to get source lines on this CU.\n");
+                return -ENOENT;
+        }
+        pr_debug2("Get %zd lines from this CU\n", nlines);
+
+        /* Walk on the lines on lines list */
+        for (i = 0; i < nlines; i++) {
+                line = dwarf_onesrcline(lines, i);
+                if (line == NULL ||
+                    dwarf_lineno(line, &lineno) != 0 ||
+                    dwarf_lineaddr(line, &addr) != 0) {
+                        pr_debug2("Failed to get line info. "
+                                  "Possible error in debuginfo.\n");
+                        continue;
+                }
+                /* Filter lines based on address */
+                if (pdie != cu_die)
+                        /*
+                         * Address filtering
+                         * The line is included in given function, and
+                         * no inline block includes it.
+                         */
+                        if (!dwarf_haspc(pdie, addr) ||
+                            die_find_inlinefunc(pdie, addr, &die_mem))
+                                continue;
+                /* Get source line */
+                fname = dwarf_linesrc(line, NULL, NULL);
+
+                ret = handler(fname, lineno, addr, data);
+                if (ret != 0)
+                        return ret;
+        }
+
+        /*
+         * Dwarf lines doesn't include function declarations and inlined
+         * subroutines. We have to check functions list or given function.
+         */
+        if (pdie != cu_die)
+                ret = __die_walk_funclines(pdie, handler, data);
+        else {
+                struct __line_walk_param param = {
+                        .handler = handler,
+                        .data = data,
+                        .retval = 0,
+                };
+                dwarf_getfuncs(cu_die, __die_walk_culines_cb, &param, 0);
+                ret = param.retval;
+        }
+
+        return ret;
+}
+
 struct __find_variable_param {
         const char *name;
         Dwarf_Addr addr;
@@ -1050,43 +1168,26 @@ static int call_probe_finder(Dwarf_Die *sp_die, struct probe_finder *pf)
         return ret;
 }
 
-/* Find probe point from its line number */
-static int find_probe_point_by_line(struct probe_finder *pf)
+static int probe_point_line_walker(const char *fname, int lineno,
+                                   Dwarf_Addr addr, void *data)
 {
-        Dwarf_Lines *lines;
-        Dwarf_Line *line;
-        size_t nlines, i;
-        Dwarf_Addr addr;
-        int lineno;
-        int ret = 0;
+        struct probe_finder *pf = data;
+        int ret;
 
-        if (dwarf_getsrclines(&pf->cu_die, &lines, &nlines) != 0) {
-                pr_warning("No source lines found.\n");
-                return -ENOENT;
-        }
+        if (lineno != pf->lno || strtailcmp(fname, pf->fname) != 0)
+                return 0;
 
-        for (i = 0; i < nlines && ret == 0; i++) {
-                line = dwarf_onesrcline(lines, i);
-                if (dwarf_lineno(line, &lineno) != 0 ||
-                    lineno != pf->lno)
-                        continue;
+        pf->addr = addr;
+        ret = call_probe_finder(NULL, pf);
 
-                /* TODO: Get fileno from line, but how? */
-                if (strtailcmp(dwarf_linesrc(line, NULL, NULL), pf->fname) != 0)
-                        continue;
-
-                if (dwarf_lineaddr(line, &addr) != 0) {
-                        pr_warning("Failed to get the address of the line.\n");
-                        return -ENOENT;
-                }
-                pr_debug("Probe line found: line[%d]:%d addr:0x%jx\n",
-                         (int)i, lineno, (uintmax_t)addr);
-                pf->addr = addr;
+        /* Continue if no error, because the line will be in inline function */
+        return ret < 0 ?: 0;
+}
 
-                ret = call_probe_finder(NULL, pf);
-                /* Continuing, because target line might be inlined. */
-        }
-        return ret;
+/* Find probe point from its line number */
+static int find_probe_point_by_line(struct probe_finder *pf)
+{
+        return die_walk_lines(&pf->cu_die, probe_point_line_walker, pf);
 }
 
 /* Find lines which match lazy pattern */
@@ -1140,15 +1241,31 @@ out_close:
         return nlines;
 }
 
+static int probe_point_lazy_walker(const char *fname, int lineno,
+                                   Dwarf_Addr addr, void *data)
+{
+        struct probe_finder *pf = data;
+        int ret;
+
+        if (!line_list__has_line(&pf->lcache, lineno) ||
+            strtailcmp(fname, pf->fname) != 0)
+                return 0;
+
+        pr_debug("Probe line found: line:%d addr:0x%llx\n",
+                 lineno, (unsigned long long)addr);
+        pf->addr = addr;
+        ret = call_probe_finder(NULL, pf);
+
+        /*
+         * Continue if no error, because the lazy pattern will match
+         * to other lines
+         */
+        return ret < 0 ?: 0;
+}
+
 /* Find probe points from lazy pattern  */
 static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
 {
-        Dwarf_Lines *lines;
-        Dwarf_Line *line;
-        size_t nlines, i;
-        Dwarf_Addr addr;
-        Dwarf_Die die_mem;
-        int lineno;
         int ret = 0;
 
         if (list_empty(&pf->lcache)) {
@@ -1162,45 +1279,7 @@ static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
                         return ret;
         }
 
-        if (dwarf_getsrclines(&pf->cu_die, &lines, &nlines) != 0) {
-                pr_warning("No source lines found.\n");
-                return -ENOENT;
-        }
-
-        for (i = 0; i < nlines && ret >= 0; i++) {
-                line = dwarf_onesrcline(lines, i);
-
-                if (dwarf_lineno(line, &lineno) != 0 ||
-                    !line_list__has_line(&pf->lcache, lineno))
-                        continue;
-
-                /* TODO: Get fileno from line, but how? */
-                if (strtailcmp(dwarf_linesrc(line, NULL, NULL), pf->fname) != 0)
-                        continue;
-
-                if (dwarf_lineaddr(line, &addr) != 0) {
-                        pr_debug("Failed to get the address of line %d.\n",
-                                 lineno);
-                        continue;
-                }
-                if (sp_die) {
-                        /* Address filtering 1: does sp_die include addr? */
-                        if (!dwarf_haspc(sp_die, addr))
-                                continue;
-                        /* Address filtering 2: No child include addr? */
-                        if (die_find_inlinefunc(sp_die, addr, &die_mem))
-                                continue;
-                }
-
-                pr_debug("Probe line found: line[%d]:%d addr:0x%llx\n",
-                         (int)i, lineno, (unsigned long long)addr);
-                pf->addr = addr;
-
-                ret = call_probe_finder(sp_die, pf);
-                /* Continuing, because target line might be inlined. */
-        }
-        /* TODO: deallocate lines, but how? */
-        return ret;
+        return die_walk_lines(sp_die, probe_point_lazy_walker, pf);
 }
 
 /* Callback parameter with return value */
@@ -1644,91 +1723,28 @@ static int line_range_add_line(const char *src, unsigned int lineno,
         return line_list__add_line(&lr->line_list, lineno);
 }
 
-/* Search function declaration lines */
-static int line_range_funcdecl_cb(Dwarf_Die *sp_die, void *data)
+static int line_range_walk_cb(const char *fname, int lineno,
+                              Dwarf_Addr addr __used,
+                              void *data)
 {
-        struct dwarf_callback_param *param = data;
-        struct line_finder *lf = param->data;
-        const char *src;
-        int lineno;
-
-        src = dwarf_decl_file(sp_die);
-        if (src && strtailcmp(src, lf->fname) != 0)
-                return DWARF_CB_OK;
+        struct line_finder *lf = data;
 
-        if (dwarf_decl_line(sp_die, &lineno) != 0 ||
+        if ((strtailcmp(fname, lf->fname) != 0) ||
             (lf->lno_s > lineno || lf->lno_e < lineno))
-                return DWARF_CB_OK;
+                return 0;
 
-        param->retval = line_range_add_line(src, lineno, lf->lr);
-        if (param->retval < 0)
-                return DWARF_CB_ABORT;
-        return DWARF_CB_OK;
-}
+        if (line_range_add_line(fname, lineno, lf->lr) < 0)
+                return -EINVAL;
 
-static int find_line_range_func_decl_lines(struct line_finder *lf)
-{
-        struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
-        dwarf_getfuncs(&lf->cu_die, line_range_funcdecl_cb, &param, 0);
-        return param.retval;
+        return 0;
 }
 
 /* Find line range from its line number */
 static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
 {
-        Dwarf_Lines *lines;
-        Dwarf_Line *line;
-        size_t nlines, i;
-        Dwarf_Addr addr;
-        int lineno, ret = 0;
-        const char *src;
-        Dwarf_Die die_mem;
-
-        line_list__init(&lf->lr->line_list);
-        if (dwarf_getsrclines(&lf->cu_die, &lines, &nlines) != 0) {
-                pr_warning("No source lines found.\n");
-                return -ENOENT;
-        }
-
-        /* Search probable lines on lines list */
-        for (i = 0; i < nlines; i++) {
-                line = dwarf_onesrcline(lines, i);
-                if (dwarf_lineno(line, &lineno) != 0 ||
-                    (lf->lno_s > lineno || lf->lno_e < lineno))
-                        continue;
-
-                if (sp_die) {
-                        /* Address filtering 1: does sp_die include addr? */
-                        if (dwarf_lineaddr(line, &addr) != 0 ||
-                            !dwarf_haspc(sp_die, addr))
-                                continue;
-
-                        /* Address filtering 2: No child include addr? */
-                        if (die_find_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;
-
-                ret = line_range_add_line(src, lineno, lf->lr);
-                if (ret < 0)
-                        return ret;
-        }
+        int ret;
 
-        /*
-         * Dwarf lines doesn't include function declarations. We have to
-         * check functions list or given function.
-         */
-        if (sp_die) {
-                src = dwarf_decl_file(sp_die);
-                if (src && dwarf_decl_line(sp_die, &lineno) == 0 &&
-                    (lf->lno_s <= lineno && lf->lno_e >= lineno))
-                        ret = line_range_add_line(src, lineno, lf->lr);
-        } else
-                ret = find_line_range_func_decl_lines(lf);
+        ret = die_walk_lines(sp_die ?: &lf->cu_die, line_range_walk_cb, lf);
 
         /* Update status */
         if (ret >= 0)
@@ -1758,9 +1774,6 @@ static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
         struct line_finder *lf = param->data;
         struct line_range *lr = lf->lr;
 
-        pr_debug("find (%llx) %s\n",
-                 (unsigned long long)dwarf_dieoffset(sp_die),
-                 dwarf_diename(sp_die));
         if (dwarf_tag(sp_die) == DW_TAG_subprogram &&
             die_compare_name(sp_die, lr->function)) {
                 lf->fname = dwarf_decl_file(sp_die);