perf probe: Add basic module support

Add basic module probe support on perf probe. This introduces "--module
<MODNAME>" option to perf probe for putting probes and showing lines and
variables in the given module.

Currently, this supports only probing on running modules.  Supporting off-line
module probing is the next step.

e.g.)
[show lines]
 # ./perf probe --module drm -L drm_vblank_info
<drm_vblank_info:0>
      0  int drm_vblank_info(struct seq_file *m, void *data)
      1  {
                struct drm_info_node *node = (struct drm_info_node *) m->private
      3         struct drm_device *dev = node->minor->dev;
 ...
[show vars]
 # ./perf probe --module drm -V drm_vblank_info:3
Available variables at drm_vblank_info:3
        @<drm_vblank_info+20>
                (unknown_type)  data
                struct drm_info_node*   node
                struct seq_file*        m
[put a probe]
 # ./perf probe --module drm drm_vblank_info:3 node m
Add new event:
  probe:drm_vblank_info (on drm_vblank_info:3 with node m)

You can now use it on all perf tools, such as:

        perf record -e probe:drm_vblank_info -aR sleep 1
[list probes]
 # ./perf probe -l
probe:drm_vblank_info (on drm_vblank_info:3@drivers/gpu/drm/drm_info.c with ...

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20101021101341.3542.71638.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>

7 files changed, 239 insertions, 69 deletions

diff --git a/tools/perf/Documentation/perf-probe.txt b/tools/perf/Documentation/perf-probe.txt
index 148c178a35aa..62de1b7f4e76 100644
--- a/tools/perf/Documentation/perf-probe.txt
+++ b/tools/perf/Documentation/perf-probe.txt
@@ -16,9 +16,9 @@ or
 or
 'perf probe' --list
 or
-'perf probe' --line='FUNC[:RLN[+NUM|:RLN2]]|SRC:ALN[+NUM|:ALN2]'
+'perf probe' [options] --line='FUNC[:RLN[+NUM|:RLN2]]|SRC:ALN[+NUM|:ALN2]'
 or
-'perf probe' [--externs] --vars='PROBEPOINT'
+'perf probe' [options] --vars='PROBEPOINT'
 
 DESCRIPTION
 -----------
@@ -33,6 +33,11 @@ OPTIONS
 --vmlinux=PATH::
         Specify vmlinux path which has debuginfo (Dwarf binary).
 
+-m::
+--module=MODNAME::
+        Specify module name in which perf-probe searches probe points
+        or lines.
+
 -s::
 --source=PATH::
         Specify path to kernel source.
diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index bdf60cfdf70f..2e000c068cc5 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -57,6 +57,7 @@ static struct {
         struct perf_probe_event events[MAX_PROBES];
         struct strlist *dellist;
         struct line_range line_range;
+        const char *target_module;
         int max_probe_points;
 } params;
 
@@ -162,8 +163,8 @@ static const char * const probe_usage[] = {
         "perf probe [<options>] --del '[GROUP:]EVENT' ...",
         "perf probe --list",
 #ifdef DWARF_SUPPORT
-        "perf probe --line 'LINEDESC'",
-        "perf probe [--externs] --vars 'PROBEPOINT'",
+        "perf probe [<options>] --line 'LINEDESC'",
+        "perf probe [<options>] --vars 'PROBEPOINT'",
 #endif
         NULL
 };
@@ -214,6 +215,8 @@ static const struct option options[] = {
                    "file", "vmlinux pathname"),
         OPT_STRING('s', "source", &symbol_conf.source_prefix,
                    "directory", "path to kernel source"),
+        OPT_STRING('m', "module", &params.target_module,
+                   "modname", "target module name"),
 #endif
         OPT__DRY_RUN(&probe_event_dry_run),
         OPT_INTEGER('\0', "max-probes", &params.max_probe_points,
@@ -278,7 +281,7 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
                         usage_with_options(probe_usage, options);
                 }
 
-                ret = show_line_range(&params.line_range);
+                ret = show_line_range(&params.line_range, params.target_module);
                 if (ret < 0)
                         pr_err("  Error: Failed to show lines. (%d)\n", ret);
                 return ret;
@@ -291,6 +294,7 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
                 }
                 ret = show_available_vars(params.events, params.nevents,
                                           params.max_probe_points,
+                                          params.target_module,
                                           params.show_ext_vars);
                 if (ret < 0)
                         pr_err("  Error: Failed to show vars. (%d)\n", ret);
@@ -310,6 +314,7 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
         if (params.nevents) {
                 ret = add_perf_probe_events(params.events, params.nevents,
                                             params.max_probe_points,
+                                            params.target_module,
                                             params.force_add);
                 if (ret < 0) {
                         pr_err("  Error: Failed to add events. (%d)\n", ret);
diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h
index 78575796d5f3..b397c0383728 100644
--- a/tools/perf/util/map.h
+++ b/tools/perf/util/map.h
@@ -215,6 +215,16 @@ struct symbol *map_groups__find_function_by_name(struct map_groups *self,
         return map_groups__find_symbol_by_name(self, MAP__FUNCTION, name, mapp, filter);
 }
 
+static inline
+struct symbol *machine__find_kernel_function_by_name(struct machine *self,
+                                                     const char *name,
+                                                     struct map **mapp,
+                                                     symbol_filter_t filter)
+{
+        return map_groups__find_function_by_name(&self->kmaps, name, mapp,
+                                                 filter);
+}
+
 int map_groups__fixup_overlappings(struct map_groups *self, struct map *map,
                                    int verbose, FILE *fp);
 
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 82b0976e2053..3b6a5297bf16 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -74,10 +74,9 @@ static int e_snprintf(char *str, size_t size, const char *format, ...)
 static char *synthesize_perf_probe_point(struct perf_probe_point *pp);
 static struct machine machine;
 
-/* Initialize symbol maps and path of vmlinux */
+/* Initialize symbol maps and path of vmlinux/modules */
 static int init_vmlinux(void)
 {
-        struct dso *kernel;
         int ret;
 
         symbol_conf.sort_by_name = true;
@@ -91,33 +90,61 @@ static int init_vmlinux(void)
                 goto out;
         }
 
-        ret = machine__init(&machine, "/", 0);
+        ret = machine__init(&machine, "", HOST_KERNEL_ID);
         if (ret < 0)
                 goto out;
 
-        kernel = dso__new_kernel(symbol_conf.vmlinux_name);
-        if (kernel == NULL)
-                die("Failed to create kernel dso.");
-
-        ret = __machine__create_kernel_maps(&machine, kernel);
-        if (ret < 0)
-                pr_debug("Failed to create kernel maps.\n");
-
+        if (machine__create_kernel_maps(&machine) < 0) {
+                pr_debug("machine__create_kernel_maps ");
+                goto out;
+        }
 out:
         if (ret < 0)
                 pr_warning("Failed to init vmlinux path.\n");
         return ret;
 }
 
+static struct symbol *__find_kernel_function_by_name(const char *name,
+                                                     struct map **mapp)
+{
+        return machine__find_kernel_function_by_name(&machine, name, mapp,
+                                                     NULL);
+}
+
+const char *kernel_get_module_path(const char *module)
+{
+        struct dso *dso;
+
+        if (module) {
+                list_for_each_entry(dso, &machine.kernel_dsos, node) {
+                        if (strncmp(dso->short_name + 1, module,
+                                    dso->short_name_len - 2) == 0)
+                                goto found;
+                }
+                pr_debug("Failed to find module %s.\n", module);
+                return NULL;
+        } else {
+                dso = machine.vmlinux_maps[MAP__FUNCTION]->dso;
+                if (dso__load_vmlinux_path(dso,
+                         machine.vmlinux_maps[MAP__FUNCTION], NULL) < 0) {
+                        pr_debug("Failed to load kernel map.\n");
+                        return NULL;
+                }
+        }
+found:
+        return dso->long_name;
+}
+
 #ifdef DWARF_SUPPORT
-static int open_vmlinux(void)
+static int open_vmlinux(const char *module)
 {
-        if (map__load(machine.vmlinux_maps[MAP__FUNCTION], NULL) < 0) {
-                pr_debug("Failed to load kernel map.\n");
-                return -EINVAL;
+        const char *path = kernel_get_module_path(module);
+        if (!path) {
+                pr_err("Failed to find path of %s module", module ?: "kernel");
+                return -ENOENT;
         }
-        pr_debug("Try to open %s\n", machine.vmlinux_maps[MAP__FUNCTION]->dso->long_name);
-        return open(machine.vmlinux_maps[MAP__FUNCTION]->dso->long_name, O_RDONLY);
+        pr_debug("Try to open %s\n", path);
+        return open(path, O_RDONLY);
 }
 
 /*
@@ -125,20 +152,19 @@ static int open_vmlinux(void)
  * Currently only handles kprobes.
  */
 static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
-                                       struct perf_probe_point *pp)
+                                        struct perf_probe_point *pp)
 {
         struct symbol *sym;
-        int fd, ret = -ENOENT;
+        struct map *map;
+        u64 addr;
+        int ret = -ENOENT;
 
-        sym = map__find_symbol_by_name(machine.vmlinux_maps[MAP__FUNCTION],
-                                       tp->symbol, NULL);
+        sym = __find_kernel_function_by_name(tp->symbol, &map);
         if (sym) {
-                fd = open_vmlinux();
-                if (fd >= 0) {
-                        ret = find_perf_probe_point(fd,
-                                                 sym->start + tp->offset, pp);
-                        close(fd);
-                }
+                addr = map->unmap_ip(map, sym->start + tp->offset);
+                pr_debug("try to find %s+%ld@%llx\n", tp->symbol,
+                         tp->offset, addr);
+                ret = find_perf_probe_point((unsigned long)addr, pp);
         }
         if (ret <= 0) {
                 pr_debug("Failed to find corresponding probes from "
@@ -156,12 +182,12 @@ static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
 /* Try to find perf_probe_event with debuginfo */
 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
                                            struct probe_trace_event **tevs,
-                                           int max_tevs)
+                                           int max_tevs, const char *module)
 {
         bool need_dwarf = perf_probe_event_need_dwarf(pev);
         int fd, ntevs;
 
-        fd = open_vmlinux();
+        fd = open_vmlinux(module);
         if (fd < 0) {
                 if (need_dwarf) {
                         pr_warning("Failed to open debuginfo file.\n");
@@ -300,7 +326,7 @@ error:
  * Show line-range always requires debuginfo to find source file and
  * line number.
  */
-int show_line_range(struct line_range *lr)
+int show_line_range(struct line_range *lr, const char *module)
 {
         int l = 1;
         struct line_node *ln;
@@ -313,7 +339,7 @@ int show_line_range(struct line_range *lr)
         if (ret < 0)
                 return ret;
 
-        fd = open_vmlinux();
+        fd = open_vmlinux(module);
         if (fd < 0) {
                 pr_warning("Failed to open debuginfo file.\n");
                 return fd;
@@ -421,7 +447,7 @@ static int show_available_vars_at(int fd, struct perf_probe_event *pev,
 
 /* Show available variables on given probe point */
 int show_available_vars(struct perf_probe_event *pevs, int npevs,
-                        int max_vls, bool externs)
+                        int max_vls, const char *module, bool externs)
 {
         int i, fd, ret = 0;
 
@@ -429,7 +455,7 @@ int show_available_vars(struct perf_probe_event *pevs, int npevs,
         if (ret < 0)
                 return ret;
 
-        fd = open_vmlinux();
+        fd = open_vmlinux(module);
         if (fd < 0) {
                 pr_warning("Failed to open debuginfo file.\n");
                 return fd;
@@ -447,8 +473,15 @@ int show_available_vars(struct perf_probe_event *pevs, int npevs,
 #else   /* !DWARF_SUPPORT */
 
 static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
-                                       struct perf_probe_point *pp)
+                                        struct perf_probe_point *pp)
 {
+        struct symbol *sym;
+
+        sym = __find_kernel_function_by_name(tp->symbol, NULL);
+        if (!sym) {
+                pr_err("Failed to find symbol %s in kernel.\n", tp->symbol);
+                return -ENOENT;
+        }
         pp->function = strdup(tp->symbol);
         if (pp->function == NULL)
                 return -ENOMEM;
@@ -460,7 +493,7 @@ static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
 
 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
                                 struct probe_trace_event **tevs __unused,
-                                int max_tevs __unused)
+                                int max_tevs __unused, const char *mod __unused)
 {
         if (perf_probe_event_need_dwarf(pev)) {
                 pr_warning("Debuginfo-analysis is not supported.\n");
@@ -469,14 +502,15 @@ static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
         return 0;
 }
 
-int show_line_range(struct line_range *lr __unused)
+int show_line_range(struct line_range *lr __unused, const char *module __unused)
 {
         pr_warning("Debuginfo-analysis is not supported.\n");
         return -ENOSYS;
 }
 
 int show_available_vars(struct perf_probe_event *pevs __unused,
-                        int npevs __unused, int max_probe_points __unused)
+                        int npevs __unused, int max_vls __unused,
+                        const char *module __unused, bool externs __unused)
 {
         pr_warning("Debuginfo-analysis is not supported.\n");
         return -ENOSYS;
@@ -1159,7 +1193,7 @@ error:
 }
 
 static int convert_to_perf_probe_event(struct probe_trace_event *tev,
-                                struct perf_probe_event *pev)
+                                       struct perf_probe_event *pev)
 {
         char buf[64] = "";
         int i, ret;
@@ -1588,14 +1622,14 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
 
 static int convert_to_probe_trace_events(struct perf_probe_event *pev,
                                           struct probe_trace_event **tevs,
-                                          int max_tevs)
+                                          int max_tevs, const char *module)
 {
         struct symbol *sym;
         int ret = 0, i;
         struct probe_trace_event *tev;
 
         /* Convert perf_probe_event with debuginfo */
-        ret = try_to_find_probe_trace_events(pev, tevs, max_tevs);
+        ret = try_to_find_probe_trace_events(pev, tevs, max_tevs, module);
         if (ret != 0)
                 return ret;
 
@@ -1644,8 +1678,7 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev,
         }
 
         /* Currently just checking function name from symbol map */
-        sym = map__find_symbol_by_name(machine.vmlinux_maps[MAP__FUNCTION],
-                                       tev->point.symbol, NULL);
+        sym = __find_kernel_function_by_name(tev->point.symbol, NULL);
         if (!sym) {
                 pr_warning("Kernel symbol \'%s\' not found.\n",
                            tev->point.symbol);
@@ -1668,7 +1701,7 @@ struct __event_package {
 };
 
 int add_perf_probe_events(struct perf_probe_event *pevs, int npevs,
-                          int max_tevs, bool force_add)
+                          int max_tevs, const char *module, bool force_add)
 {
         int i, j, ret;
         struct __event_package *pkgs;
@@ -1689,7 +1722,9 @@ int add_perf_probe_events(struct perf_probe_event *pevs, int npevs,
                 pkgs[i].pev = &pevs[i];
                 /* Convert with or without debuginfo */
                 ret  = convert_to_probe_trace_events(pkgs[i].pev,
-                                                      &pkgs[i].tevs, max_tevs);
+                                                     &pkgs[i].tevs,
+                                                     max_tevs,
+                                                     module);
                 if (ret < 0)
                         goto end;
                 pkgs[i].ntevs = ret;
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index c74b1fd2c1fa..5accbedfea37 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -115,14 +115,18 @@ extern void clear_perf_probe_event(struct perf_probe_event *pev);
 /* Command string to line-range */
 extern int parse_line_range_desc(const char *cmd, struct line_range *lr);
 
+/* Internal use: Return kernel/module path */
+extern const char *kernel_get_module_path(const char *module);
 
 extern int add_perf_probe_events(struct perf_probe_event *pevs, int npevs,
-                                 int max_probe_points, bool force_add);
+                                 int max_probe_points, const char *module,
+                                 bool force_add);
 extern int del_perf_probe_events(struct strlist *dellist);
 extern int show_perf_probe_events(void);
-extern int show_line_range(struct line_range *lr);
+extern int show_line_range(struct line_range *lr, const char *module);
 extern int show_available_vars(struct perf_probe_event *pevs, int npevs,
-                               int max_probe_points, bool externs);
+                               int max_probe_points, const char *module,
+                               bool externs);
 
 
 /* Maximum index number of event-name postfix */
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index a274fd0c143e..c20bd52833aa 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -116,6 +116,101 @@ static void line_list__free(struct list_head *head)
         }
 }
 
+/* Dwarf FL wrappers */
+
+static int __linux_kernel_find_elf(Dwfl_Module *mod,
+                                   void **userdata,
+                                   const char *module_name,
+                                   Dwarf_Addr base,
+                                   char **file_name, Elf **elfp)
+{
+        int fd;
+        const char *path = kernel_get_module_path(module_name);
+
+        if (path) {
+                fd = open(path, O_RDONLY);
+                if (fd >= 0) {
+                        *file_name = strdup(path);
+                        return fd;
+                }
+        }
+        /* If failed, try to call standard method */
+        return dwfl_linux_kernel_find_elf(mod, userdata, module_name, base,
+                                          file_name, elfp);
+}
+
+static char *debuginfo_path;    /* Currently dummy */
+
+static const Dwfl_Callbacks offline_callbacks = {
+        .find_debuginfo = dwfl_standard_find_debuginfo,
+        .debuginfo_path = &debuginfo_path,
+
+        .section_address = dwfl_offline_section_address,
+
+        /* We use this table for core files too.  */
+        .find_elf = dwfl_build_id_find_elf,
+};
+
+static const Dwfl_Callbacks kernel_callbacks = {
+        .find_debuginfo = dwfl_standard_find_debuginfo,
+        .debuginfo_path = &debuginfo_path,
+
+        .find_elf = __linux_kernel_find_elf,
+        .section_address = dwfl_linux_kernel_module_section_address,
+};
+
+/* Get a Dwarf from offline image */
+static Dwarf *dwfl_init_offline_dwarf(int fd, Dwfl **dwflp, Dwarf_Addr *bias)
+{
+        Dwfl_Module *mod;
+        Dwarf *dbg = NULL;
+
+        if (!dwflp)
+                return NULL;
+
+        *dwflp = dwfl_begin(&offline_callbacks);
+        if (!*dwflp)
+                return NULL;
+
+        mod = dwfl_report_offline(*dwflp, "", "", fd);
+        if (!mod)
+                goto error;
+
+        dbg = dwfl_module_getdwarf(mod, bias);
+        if (!dbg) {
+error:
+                dwfl_end(*dwflp);
+                *dwflp = NULL;
+        }
+        return dbg;
+}
+
+/* Get a Dwarf from live kernel image */
+static Dwarf *dwfl_init_live_kernel_dwarf(Dwarf_Addr addr, Dwfl **dwflp,
+                                          Dwarf_Addr *bias)
+{
+        Dwarf *dbg;
+
+        if (!dwflp)
+                return NULL;
+
+        *dwflp = dwfl_begin(&kernel_callbacks);
+        if (!*dwflp)
+                return NULL;
+
+        /* Load the kernel dwarves: Don't care the result here */
+        dwfl_linux_kernel_report_kernel(*dwflp);
+        dwfl_linux_kernel_report_modules(*dwflp);
+
+        dbg = dwfl_addrdwarf(*dwflp, addr, bias);
+        /* Here, check whether we could get a real dwarf */
+        if (!dbg) {
+                dwfl_end(*dwflp);
+                *dwflp = NULL;
+        }
+        return dbg;
+}
+
 /* Dwarf wrappers */
 
 /* Find the realpath of the target file. */
@@ -1177,10 +1272,12 @@ static int find_probes(int fd, struct probe_finder *pf)
         Dwarf_Off off, noff;
         size_t cuhl;
         Dwarf_Die *diep;
-        Dwarf *dbg;
+        Dwarf *dbg = NULL;
+        Dwfl *dwfl;
+        Dwarf_Addr bias;        /* Currently ignored */
         int ret = 0;
 
-        dbg = dwarf_begin(fd, DWARF_C_READ);
+        dbg = dwfl_init_offline_dwarf(fd, &dwfl, &bias);
         if (!dbg) {
                 pr_warning("No dwarf info found in the vmlinux - "
                         "please rebuild with CONFIG_DEBUG_INFO=y.\n");
@@ -1221,7 +1318,8 @@ static int find_probes(int fd, struct probe_finder *pf)
                 off = noff;
         }
         line_list__free(&pf->lcache);
-        dwarf_end(dbg);
+        if (dwfl)
+                dwfl_end(dwfl);
 
         return ret;
 }
@@ -1412,23 +1510,31 @@ int find_available_vars_at(int fd, struct perf_probe_event *pev,
 }
 
 /* Reverse search */
-int find_perf_probe_point(int fd, unsigned long addr,
-                          struct perf_probe_point *ppt)
+int find_perf_probe_point(unsigned long addr, struct perf_probe_point *ppt)
 {
         Dwarf_Die cudie, spdie, indie;
-        Dwarf *dbg;
+        Dwarf *dbg = NULL;
+        Dwfl *dwfl = NULL;
         Dwarf_Line *line;
-        Dwarf_Addr laddr, eaddr;
+        Dwarf_Addr laddr, eaddr, bias = 0;
         const char *tmp;
         int lineno, ret = 0;
         bool found = false;
 
-        dbg = dwarf_begin(fd, DWARF_C_READ);
-        if (!dbg)
-                return -EBADF;
+        /* Open the live linux kernel */
+        dbg = dwfl_init_live_kernel_dwarf(addr, &dwfl, &bias);
+        if (!dbg) {
+                pr_warning("No dwarf info found in the vmlinux - "
+                        "please rebuild with CONFIG_DEBUG_INFO=y.\n");
+                ret = -EINVAL;
+                goto end;
+        }
 
+        /* Adjust address with bias */
+        addr += bias;
         /* Find cu die */
-        if (!dwarf_addrdie(dbg, (Dwarf_Addr)addr, &cudie)) {
+        if (!dwarf_addrdie(dbg, (Dwarf_Addr)addr - bias, &cudie)) {
+                pr_warning("No CU DIE is found at %lx\n", addr);
                 ret = -EINVAL;
                 goto end;
         }
@@ -1491,7 +1597,8 @@ found:
         }
 
 end:
-        dwarf_end(dbg);
+        if (dwfl)
+                dwfl_end(dwfl);
         if (ret >= 0)
                 ret = found ? 1 : 0;
         return ret;
@@ -1624,6 +1731,8 @@ 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 (%lx) %s\n", 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);
@@ -1667,10 +1776,12 @@ int find_line_range(int fd, struct line_range *lr)
         Dwarf_Off off = 0, noff;
         size_t cuhl;
         Dwarf_Die *diep;
-        Dwarf *dbg;
+        Dwarf *dbg = NULL;
+        Dwfl *dwfl;
+        Dwarf_Addr bias;        /* Currently ignored */
         const char *comp_dir;
 
-        dbg = dwarf_begin(fd, DWARF_C_READ);
+        dbg = dwfl_init_offline_dwarf(fd, &dwfl, &bias);
         if (!dbg) {
                 pr_warning("No dwarf info found in the vmlinux - "
                         "please rebuild with CONFIG_DEBUG_INFO=y.\n");
@@ -1716,8 +1827,7 @@ int find_line_range(int fd, struct line_range *lr)
         }
 
         pr_debug("path: %s\n", lr->path);
-        dwarf_end(dbg);
-
+        dwfl_end(dwfl);
         return (ret < 0) ? ret : lf.found;
 }
 
diff --git a/tools/perf/util/probe-finder.h b/tools/perf/util/probe-finder.h
index 516912a04011..bba69d455699 100644
--- a/tools/perf/util/probe-finder.h
+++ b/tools/perf/util/probe-finder.h
@@ -22,7 +22,7 @@ extern int find_probe_trace_events(int fd, struct perf_probe_event *pev,
                                     int max_tevs);
 
 /* Find a perf_probe_point from debuginfo */
-extern int find_perf_probe_point(int fd, unsigned long addr,
+extern int find_perf_probe_point(unsigned long addr,
                                  struct perf_probe_point *ppt);
 
 /* Find a line range */
@@ -35,6 +35,7 @@ extern int find_available_vars_at(int fd, struct perf_probe_event *pev,
 
 #include <dwarf.h>
 #include <libdw.h>
+#include <libdwfl.h>
 #include <version.h>
 
 struct probe_finder {