Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core

12 files changed, 1076 insertions, 799 deletions

diff --git a/tools/perf/Documentation/perf-probe.txt b/tools/perf/Documentation/perf-probe.txt
index 02bafce4b34..2780d9ce48b 100644
--- a/tools/perf/Documentation/perf-probe.txt
+++ b/tools/perf/Documentation/perf-probe.txt
@@ -34,9 +34,11 @@ OPTIONS
 	Specify vmlinux path which has debuginfo (Dwarf binary).
 
 -m::
---module=MODNAME::
+--module=MODNAME|PATH::
 	Specify module name in which perf-probe searches probe points
-	or lines.
+	or lines. If a path of module file is passed, perf-probe
+	treat it as an offline module (this means you can add a probe on
+        a module which has not been loaded yet).
 
 -s::
 --source=PATH::
diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 940257b5774..d0861bbd1d9 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -279,6 +279,7 @@ LIB_H += util/thread.h
 LIB_H += util/thread_map.h
 LIB_H += util/trace-event.h
 LIB_H += util/probe-finder.h
+LIB_H += util/dwarf-aux.h
 LIB_H += util/probe-event.h
 LIB_H += util/pstack.h
 LIB_H += util/cpumap.h
@@ -435,6 +436,7 @@ else
 	BASIC_CFLAGS += -DDWARF_SUPPORT
 	EXTLIBS += -lelf -ldw
 	LIB_OBJS += $(OUTPUT)util/probe-finder.o
+	LIB_OBJS += $(OUTPUT)util/dwarf-aux.o
 endif # PERF_HAVE_DWARF_REGS
 endif # NO_DWARF
 
diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index 2c0e64d0b4a..5f2a5c7046d 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -242,7 +242,8 @@ static const struct option options[] = {
 	OPT_STRING('s', "source", &symbol_conf.source_prefix,
 		   "directory", "path to kernel source"),
 	OPT_STRING('m', "module", &params.target_module,
-		   "modname", "target module name"),
+		   "modname|path",
+		   "target module name (for online) or path (for offline)"),
 #endif
 	OPT__DRY_RUN(&probe_event_dry_run),
 	OPT_INTEGER('\0', "max-probes", &params.max_probe_points,
diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
new file mode 100644
index 00000000000..fddf40f30d3
--- /dev/null
+++ b/tools/perf/util/dwarf-aux.c
@@ -0,0 +1,663 @@
+/*
+ * dwarf-aux.c : libdw auxiliary interfaces
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ */
+
+#include <stdbool.h>
+#include "util.h"
+#include "debug.h"
+#include "dwarf-aux.h"
+
+/**
+ * cu_find_realpath - Find the realpath of the target file
+ * @cu_die: A DIE(dwarf information entry) of CU(compilation Unit)
+ * @fname:  The tail filename of the target file
+ *
+ * Find the real(long) path of @fname in @cu_die.
+ */
+const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname)
+{
+	Dwarf_Files *files;
+	size_t nfiles, i;
+	const char *src = NULL;
+	int ret;
+
+	if (!fname)
+		return NULL;
+
+	ret = dwarf_getsrcfiles(cu_die, &files, &nfiles);
+	if (ret != 0)
+		return NULL;
+
+	for (i = 0; i < nfiles; i++) {
+		src = dwarf_filesrc(files, i, NULL, NULL);
+		if (strtailcmp(src, fname) == 0)
+			break;
+	}
+	if (i == nfiles)
+		return NULL;
+	return src;
+}
+
+/**
+ * cu_get_comp_dir - Get the path of compilation directory
+ * @cu_die: a CU DIE
+ *
+ * Get the path of compilation directory of given @cu_die.
+ * Since this depends on DW_AT_comp_dir, older gcc will not
+ * embedded it. In that case, this returns NULL.
+ */
+const char *cu_get_comp_dir(Dwarf_Die *cu_die)
+{
+	Dwarf_Attribute attr;
+	if (dwarf_attr(cu_die, DW_AT_comp_dir, &attr) == NULL)
+		return NULL;
+	return dwarf_formstring(&attr);
+}
+
+/**
+ * cu_find_lineinfo - Get a line number and file name for given address
+ * @cu_die: a CU DIE
+ * @addr: An address
+ * @fname: a pointer which returns the file name string
+ * @lineno: a pointer which returns the line number
+ *
+ * Find a line number and file name for @addr in @cu_die.
+ */
+int cu_find_lineinfo(Dwarf_Die *cu_die, unsigned long addr,
+		    const char **fname, int *lineno)
+{
+	Dwarf_Line *line;
+	Dwarf_Addr laddr;
+
+	line = dwarf_getsrc_die(cu_die, (Dwarf_Addr)addr);
+	if (line && dwarf_lineaddr(line, &laddr) == 0 &&
+	    addr == (unsigned long)laddr && dwarf_lineno(line, lineno) == 0) {
+		*fname = dwarf_linesrc(line, NULL, NULL);
+		if (!*fname)
+			/* line number is useless without filename */
+			*lineno = 0;
+	}
+
+	return *lineno ?: -ENOENT;
+}
+
+/**
+ * die_compare_name - Compare diename and tname
+ * @dw_die: a DIE
+ * @tname: a string of target name
+ *
+ * Compare the name of @dw_die and @tname. Return false if @dw_die has no name.
+ */
+bool die_compare_name(Dwarf_Die *dw_die, const char *tname)
+{
+	const char *name;
+	name = dwarf_diename(dw_die);
+	return name ? (strcmp(tname, name) == 0) : false;
+}
+
+/**
+ * die_get_call_lineno - Get callsite line number of inline-function instance
+ * @in_die: a DIE of an inlined function instance
+ *
+ * Get call-site line number of @in_die. This means from where the inline
+ * function is called.
+ */
+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;
+}
+
+/**
+ * die_get_type - Get type DIE
+ * @vr_die: a DIE of a variable
+ * @die_mem: where to store a type DIE
+ *
+ * Get a DIE of the type of given variable (@vr_die), and store
+ * it to die_mem. Return NULL if fails to get a type DIE.
+ */
+Dwarf_Die *die_get_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
+{
+	Dwarf_Attribute attr;
+
+	if (dwarf_attr_integrate(vr_die, DW_AT_type, &attr) &&
+	    dwarf_formref_die(&attr, die_mem))
+		return die_mem;
+	else
+		return NULL;
+}
+
+/* Get a type die, but skip qualifiers */
+static Dwarf_Die *__die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
+{
+	int tag;
+
+	do {
+		vr_die = die_get_type(vr_die, die_mem);
+		if (!vr_die)
+			break;
+		tag = dwarf_tag(vr_die);
+	} while (tag == DW_TAG_const_type ||
+		 tag == DW_TAG_restrict_type ||
+		 tag == DW_TAG_volatile_type ||
+		 tag == DW_TAG_shared_type);
+
+	return vr_die;
+}
+
+/**
+ * die_get_real_type - Get a type die, but skip qualifiers and typedef
+ * @vr_die: a DIE of a variable
+ * @die_mem: where to store a type DIE
+ *
+ * Get a DIE of the type of given variable (@vr_die), and store
+ * it to die_mem. Return NULL if fails to get a type DIE.
+ * If the type is qualifiers (e.g. const) or typedef, this skips it
+ * and tries to find real type (structure or basic types, e.g. int).
+ */
+Dwarf_Die *die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
+{
+	do {
+		vr_die = __die_get_real_type(vr_die, die_mem);
+	} while (vr_die && dwarf_tag(vr_die) == DW_TAG_typedef);
+
+	return vr_die;
+}
+
+/* Get attribute and translate it as a udata */
+static int die_get_attr_udata(Dwarf_Die *tp_die, unsigned int attr_name,
+			      Dwarf_Word *result)
+{
+	Dwarf_Attribute attr;
+
+	if (dwarf_attr(tp_die, attr_name, &attr) == NULL ||
+	    dwarf_formudata(&attr, result) != 0)
+		return -ENOENT;
+
+	return 0;
+}
+
+/**
+ * die_is_signed_type - Check whether a type DIE is signed or not
+ * @tp_die: a DIE of a type
+ *
+ * Get the encoding of @tp_die and return true if the encoding
+ * is signed.
+ */
+bool die_is_signed_type(Dwarf_Die *tp_die)
+{
+	Dwarf_Word ret;
+
+	if (die_get_attr_udata(tp_die, DW_AT_encoding, &ret))
+		return false;
+
+	return (ret == DW_ATE_signed_char || ret == DW_ATE_signed ||
+		ret == DW_ATE_signed_fixed);
+}
+
+/**
+ * die_get_data_member_location - Get the data-member offset
+ * @mb_die: a DIE of a member of a data structure
+ * @offs: The offset of the member in the data structure
+ *
+ * Get the offset of @mb_die in the data structure including @mb_die, and
+ * stores result offset to @offs. If any error occurs this returns errno.
+ */
+int die_get_data_member_location(Dwarf_Die *mb_die, Dwarf_Word *offs)
+{
+	Dwarf_Attribute attr;
+	Dwarf_Op *expr;
+	size_t nexpr;
+	int ret;
+
+	if (dwarf_attr(mb_die, DW_AT_data_member_location, &attr) == NULL)
+		return -ENOENT;
+
+	if (dwarf_formudata(&attr, offs) != 0) {
+		/* DW_AT_data_member_location should be DW_OP_plus_uconst */
+		ret = dwarf_getlocation(&attr, &expr, &nexpr);
+		if (ret < 0 || nexpr == 0)
+			return -ENOENT;
+
+		if (expr[0].atom != DW_OP_plus_uconst || nexpr != 1) {
+			pr_debug("Unable to get offset:Unexpected OP %x (%zd)\n",
+				 expr[0].atom, nexpr);
+			return -ENOTSUP;
+		}
+		*offs = (Dwarf_Word)expr[0].number;
+	}
+	return 0;
+}
+
+/**
+ * die_find_child - Generic DIE search function in DIE tree
+ * @rt_die: a root DIE
+ * @callback: a callback function
+ * @data: a user data passed to the callback function
+ * @die_mem: a buffer for result DIE
+ *
+ * Trace DIE tree from @rt_die and call @callback for each child DIE.
+ * If @callback returns DIE_FIND_CB_END, this stores the DIE into
+ * @die_mem and returns it. If @callback returns DIE_FIND_CB_CONTINUE,
+ * this continues to trace the tree. Optionally, @callback can return
+ * DIE_FIND_CB_CHILD and DIE_FIND_CB_SIBLING, those means trace only
+ * the children and trace only the siblings respectively.
+ * Returns NULL if @callback can't find any appropriate DIE.
+ */
+Dwarf_Die *die_find_child(Dwarf_Die *rt_die,
+			  int (*callback)(Dwarf_Die *, void *),
+			  void *data, Dwarf_Die *die_mem)
+{
+	Dwarf_Die child_die;
+	int ret;
+
+	ret = dwarf_child(rt_die, die_mem);
+	if (ret != 0)
+		return NULL;
+
+	do {
+		ret = callback(die_mem, data);
+		if (ret == DIE_FIND_CB_END)
+			return die_mem;
+
+		if ((ret & DIE_FIND_CB_CHILD) &&
+		    die_find_child(die_mem, callback, data, &child_die)) {
+			memcpy(die_mem, &child_die, sizeof(Dwarf_Die));
+			return die_mem;
+		}
+	} while ((ret & DIE_FIND_CB_SIBLING) &&
+		 dwarf_siblingof(die_mem, die_mem) == 0);
+
+	return NULL;
+}
+
+struct __addr_die_search_param {
+	Dwarf_Addr	addr;
+	Dwarf_Die	*die_mem;
+};
+
+/* die_find callback for non-inlined function search */
+static int __die_search_func_cb(Dwarf_Die *fn_die, void *data)
+{
+	struct __addr_die_search_param *ad = data;
+
+	if (dwarf_tag(fn_die) == DW_TAG_subprogram &&
+	    dwarf_haspc(fn_die, ad->addr)) {
+		memcpy(ad->die_mem, fn_die, sizeof(Dwarf_Die));
+		return DWARF_CB_ABORT;
+	}
+	return DWARF_CB_OK;
+}
+
+/**
+ * die_find_realfunc - Search a non-inlined function at given address
+ * @cu_die: a CU DIE which including @addr
+ * @addr: target address
+ * @die_mem: a buffer for result DIE
+ *
+ * Search a non-inlined function DIE which includes @addr. Stores the
+ * DIE to @die_mem and returns it if found. Returns NULl if failed.
+ */
+Dwarf_Die *die_find_realfunc(Dwarf_Die *cu_die, Dwarf_Addr addr,
+				    Dwarf_Die *die_mem)
+{
+	struct __addr_die_search_param ad;
+	ad.addr = addr;
+	ad.die_mem = die_mem;
+	/* dwarf_getscopes can't find subprogram. */
+	if (!dwarf_getfuncs(cu_die, __die_search_func_cb, &ad, 0))
+		return NULL;
+	else
+		return die_mem;
+}
+
+/* die_find callback for inline function search */
+static int __die_find_inline_cb(Dwarf_Die *die_mem, void *data)
+{
+	Dwarf_Addr *addr = data;
+
+	if (dwarf_tag(die_mem) == DW_TAG_inlined_subroutine &&
+	    dwarf_haspc(die_mem, *addr))
+		return DIE_FIND_CB_END;
+
+	return DIE_FIND_CB_CONTINUE;
+}
+
+/**
+ * die_find_inlinefunc - Search an inlined function at given address
+ * @cu_die: a CU DIE which including @addr
+ * @addr: target address
+ * @die_mem: a buffer for result DIE
+ *
+ * Search an inlined function DIE which includes @addr. Stores the
+ * DIE to @die_mem and returns it if found. Returns NULl if failed.
+ * If several inlined functions are expanded recursively, this trace
+ * it and returns deepest one.
+ */
+Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
+			       Dwarf_Die *die_mem)
+{
+	Dwarf_Die tmp_die;
+
+	sp_die = die_find_child(sp_die, __die_find_inline_cb, &addr, &tmp_die);
+	if (!sp_die)
+		return NULL;
+
+	/* Inlined function could be recursive. Trace it until fail */
+	while (sp_die) {
+		memcpy(die_mem, sp_die, sizeof(Dwarf_Die));
+		sp_die = die_find_child(sp_die, __die_find_inline_cb, &addr,
+					&tmp_die);
+	}
+
+	return die_mem;
+}
+
+/* Line walker internal parameters */
+struct __line_walk_param {
+	const char *fname;
+	line_walk_callback_t callback;
+	void *data;
+	int retval;
+};
+
+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->callback(lw->fname, lineno, addr,
+						  lw->data);
+			if (lw->retval != 0)
+				return DIE_FIND_CB_END;
+		}
+	}
+	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_callback_t callback, void *data)
+{
+	struct __line_walk_param lw = {
+		.callback = callback,
+		.data = data,
+		.retval = 0,
+	};
+	Dwarf_Die die_mem;
+	Dwarf_Addr addr;
+	int lineno;
+
+	/* Handle function declaration line */
+	lw.fname = dwarf_decl_file(sp_die);
+	if (lw.fname && dwarf_decl_line(sp_die, &lineno) == 0 &&
+	    dwarf_entrypc(sp_die, &addr) == 0) {
+		lw.retval = callback(lw.fname, lineno, addr, data);
+		if (lw.retval != 0)
+			goto done;
+	}
+	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)
+{
+	struct __line_walk_param *lw = data;
+
+	lw->retval = __die_walk_funclines(sp_die, lw->callback, lw->data);
+	if (lw->retval != 0)
+		return DWARF_CB_ABORT;
+
+	return DWARF_CB_OK;
+}
+
+/**
+ * die_walk_lines - Walk on lines inside given DIE
+ * @rt_die: a root DIE (CU or subprogram)
+ * @callback: callback routine
+ * @data: user data
+ *
+ * Walk on all lines inside given @rt_die and call @callback on each line.
+ * If the @rt_die is a function, walk only on the lines inside the function,
+ * otherwise @rt_die must be a CU DIE.
+ * Note that this walks not only dwarf line list, but also function entries
+ * and inline call-site.
+ */
+int die_walk_lines(Dwarf_Die *rt_die, line_walk_callback_t callback, 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(rt_die) == DW_TAG_subprogram)
+		cu_die = dwarf_diecu(rt_die, &die_mem, NULL, NULL);
+	else
+		cu_die = rt_die;
+	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 (rt_die != cu_die)
+			/*
+			 * Address filtering
+			 * The line is included in given function, and
+			 * no inline block includes it.
+			 */
+			if (!dwarf_haspc(rt_die, addr) ||
+			    die_find_inlinefunc(rt_die, addr, &die_mem))
+				continue;
+		/* Get source line */
+		fname = dwarf_linesrc(line, NULL, NULL);
+
+		ret = callback(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 (rt_die != cu_die)
+		ret = __die_walk_funclines(rt_die, callback, data);
+	else {
+		struct __line_walk_param param = {
+			.callback = callback,
+			.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;
+};
+
+static int __die_find_variable_cb(Dwarf_Die *die_mem, void *data)
+{
+	struct __find_variable_param *fvp = data;
+	int tag;
+
+	tag = dwarf_tag(die_mem);
+	if ((tag == DW_TAG_formal_parameter ||
+	     tag == DW_TAG_variable) &&
+	    die_compare_name(die_mem, fvp->name))
+		return DIE_FIND_CB_END;
+
+	if (dwarf_haspc(die_mem, fvp->addr))
+		return DIE_FIND_CB_CONTINUE;
+	else
+		return DIE_FIND_CB_SIBLING;
+}
+
+/**
+ * die_find_variable_at - Find a given name variable at given address
+ * @sp_die: a function DIE
+ * @name: variable name
+ * @addr: address
+ * @die_mem: a buffer for result DIE
+ *
+ * Find a variable DIE called @name at @addr in @sp_die.
+ */
+Dwarf_Die *die_find_variable_at(Dwarf_Die *sp_die, const char *name,
+				Dwarf_Addr addr, Dwarf_Die *die_mem)
+{
+	struct __find_variable_param fvp = { .name = name, .addr = addr};
+
+	return die_find_child(sp_die, __die_find_variable_cb, (void *)&fvp,
+			      die_mem);
+}
+
+static int __die_find_member_cb(Dwarf_Die *die_mem, void *data)
+{
+	const char *name = data;
+
+	if ((dwarf_tag(die_mem) == DW_TAG_member) &&
+	    die_compare_name(die_mem, name))
+		return DIE_FIND_CB_END;
+
+	return DIE_FIND_CB_SIBLING;
+}
+
+/**
+ * die_find_member - Find a given name member in a data structure
+ * @st_die: a data structure type DIE
+ * @name: member name
+ * @die_mem: a buffer for result DIE
+ *
+ * Find a member DIE called @name in @st_die.
+ */
+Dwarf_Die *die_find_member(Dwarf_Die *st_die, const char *name,
+			   Dwarf_Die *die_mem)
+{
+	return die_find_child(st_die, __die_find_member_cb, (void *)name,
+			      die_mem);
+}
+
+/**
+ * die_get_typename - Get the name of given variable DIE
+ * @vr_die: a variable DIE
+ * @buf: a buffer for result type name
+ * @len: a max-length of @buf
+ *
+ * Get the name of @vr_die and stores it to @buf. Return the actual length
+ * of type name if succeeded. Return -E2BIG if @len is not enough long, and
+ * Return -ENOENT if failed to find type name.
+ * Note that the result will stores typedef name if possible, and stores
+ * "*(function_type)" if the type is a function pointer.
+ */
+int die_get_typename(Dwarf_Die *vr_die, char *buf, int len)
+{
+	Dwarf_Die type;
+	int tag, ret, ret2;
+	const char *tmp = "";
+
+	if (__die_get_real_type(vr_die, &type) == NULL)
+		return -ENOENT;
+
+	tag = dwarf_tag(&type);
+	if (tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)
+		tmp = "*";
+	else if (tag == DW_TAG_subroutine_type) {
+		/* Function pointer */
+		ret = snprintf(buf, len, "(function_type)");
+		return (ret >= len) ? -E2BIG : ret;
+	} else {
+		if (!dwarf_diename(&type))
+			return -ENOENT;
+		if (tag == DW_TAG_union_type)
+			tmp = "union ";
+		else if (tag == DW_TAG_structure_type)
+			tmp = "struct ";
+		/* Write a base name */
+		ret = snprintf(buf, len, "%s%s", tmp, dwarf_diename(&type));
+		return (ret >= len) ? -E2BIG : ret;
+	}
+	ret = die_get_typename(&type, buf, len);
+	if (ret > 0) {
+		ret2 = snprintf(buf + ret, len - ret, "%s", tmp);
+		ret = (ret2 >= len - ret) ? -E2BIG : ret2 + ret;
+	}
+	return ret;
+}
+
+/**
+ * die_get_varname - Get the name and type of given variable DIE
+ * @vr_die: a variable DIE
+ * @buf: a buffer for type and variable name
+ * @len: the max-length of @buf
+ *
+ * Get the name and type of @vr_die and stores it in @buf as "type\tname".
+ */
+int die_get_varname(Dwarf_Die *vr_die, char *buf, int len)
+{
+	int ret, ret2;
+
+	ret = die_get_typename(vr_die, buf, len);
+	if (ret < 0) {
+		pr_debug("Failed to get type, make it unknown.\n");
+		ret = snprintf(buf, len, "(unknown_type)");
+	}
+	if (ret > 0) {
+		ret2 = snprintf(buf + ret, len - ret, "\t%s",
+				dwarf_diename(vr_die));
+		ret = (ret2 >= len - ret) ? -E2BIG : ret2 + ret;
+	}
+	return ret;
+}
+
diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h
new file mode 100644
index 00000000000..bc3b21167e7
--- /dev/null
+++ b/tools/perf/util/dwarf-aux.h
@@ -0,0 +1,100 @@
+#ifndef _DWARF_AUX_H
+#define _DWARF_AUX_H
+/*
+ * dwarf-aux.h : libdw auxiliary interfaces
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ */
+
+#include <dwarf.h>
+#include <elfutils/libdw.h>
+#include <elfutils/libdwfl.h>
+#include <elfutils/version.h>
+
+/* Find the realpath of the target file */
+extern const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname);
+
+/* Get DW_AT_comp_dir (should be NULL with older gcc) */
+extern const char *cu_get_comp_dir(Dwarf_Die *cu_die);
+
+/* Get a line number and file name for given address */
+extern int cu_find_lineinfo(Dwarf_Die *cudie, unsigned long addr,
+			    const char **fname, int *lineno);
+
+/* Compare diename and tname */
+extern bool die_compare_name(Dwarf_Die *dw_die, const char *tname);
+
+/* Get callsite line number of inline-function instance */
+extern int die_get_call_lineno(Dwarf_Die *in_die);
+
+/* Get type die */
+extern Dwarf_Die *die_get_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem);
+
+/* Get a type die, but skip qualifiers and typedef */
+extern Dwarf_Die *die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem);
+
+/* Check whether the DIE is signed or not */
+extern bool die_is_signed_type(Dwarf_Die *tp_die);
+
+/* Get data_member_location offset */
+extern int die_get_data_member_location(Dwarf_Die *mb_die, Dwarf_Word *offs);
+
+/* Return values for die_find_child() callbacks */
+enum {
+	DIE_FIND_CB_END = 0,		/* End of Search */
+	DIE_FIND_CB_CHILD = 1,		/* Search only children */
+	DIE_FIND_CB_SIBLING = 2,	/* Search only siblings */
+	DIE_FIND_CB_CONTINUE = 3,	/* Search children and siblings */
+};
+
+/* Search child DIEs */
+extern Dwarf_Die *die_find_child(Dwarf_Die *rt_die,
+				 int (*callback)(Dwarf_Die *, void *),
+				 void *data, Dwarf_Die *die_mem);
+
+/* Search a non-inlined function including given address */
+extern Dwarf_Die *die_find_realfunc(Dwarf_Die *cu_die, Dwarf_Addr addr,
+				    Dwarf_Die *die_mem);
+
+/* Search an inlined function including given address */
+extern Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
+				      Dwarf_Die *die_mem);
+
+/* Walker on lines (Note: line number will not be sorted) */
+typedef int (* line_walk_callback_t) (const char *fname, int lineno,
+				      Dwarf_Addr addr, void *data);
+
+/*
+ * Walk on lines inside given DIE. If the DIE is a subprogram, walk only on
+ * the lines inside the subprogram, otherwise the DIE must be a CU DIE.
+ */
+extern int die_walk_lines(Dwarf_Die *rt_die, line_walk_callback_t callback,
+			  void *data);
+
+/* Find a variable called 'name' at given address */
+extern Dwarf_Die *die_find_variable_at(Dwarf_Die *sp_die, const char *name,
+				       Dwarf_Addr addr, Dwarf_Die *die_mem);
+
+/* Find a member called 'name' */
+extern Dwarf_Die *die_find_member(Dwarf_Die *st_die, const char *name,
+				  Dwarf_Die *die_mem);
+
+/* Get the name of given variable DIE */
+extern int die_get_typename(Dwarf_Die *vr_die, char *buf, int len);
+
+/* Get the name and type of given variable DIE, stored as "type\tname" */
+extern int die_get_varname(Dwarf_Die *vr_die, char *buf, int len);
+#endif
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index f0223166e76..b82d54fa2c5 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -117,6 +117,10 @@ static struct map *kernel_get_module_map(const char *module)
 	struct rb_node *nd;
 	struct map_groups *grp = &machine.kmaps;
 
+	/* A file path -- this is an offline module */
+	if (module && strchr(module, '/'))
+		return machine__new_module(&machine, 0, module);
+
 	if (!module)
 		module = "kernel";
 
@@ -170,16 +174,24 @@ const char *kernel_get_module_path(const char *module)
 }
 
 #ifdef DWARF_SUPPORT
-static int open_vmlinux(const char *module)
+/* Open new debuginfo of given module */
+static struct debuginfo *open_debuginfo(const char *module)
 {
-	const char *path = kernel_get_module_path(module);
-	if (!path) {
-		pr_err("Failed to find path of %s module.\n",
-		       module ?: "kernel");
-		return -ENOENT;
+	const char *path;
+
+	/* A file path -- this is an offline module */
+	if (module && strchr(module, '/'))
+		path = module;
+	else {
+		path = kernel_get_module_path(module);
+
+		if (!path) {
+			pr_err("Failed to find path of %s module.\n",
+			       module ?: "kernel");
+			return NULL;
+		}
 	}
-	pr_debug("Try to open %s\n", path);
-	return open(path, O_RDONLY);
+	return debuginfo__new(path);
 }
 
 /*
@@ -193,13 +205,24 @@ static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
 	struct map *map;
 	u64 addr;
 	int ret = -ENOENT;
+	struct debuginfo *dinfo;
 
 	sym = __find_kernel_function_by_name(tp->symbol, &map);
 	if (sym) {
 		addr = map->unmap_ip(map, sym->start + tp->offset);
 		pr_debug("try to find %s+%ld@%" PRIx64 "\n", tp->symbol,
 			 tp->offset, addr);
-		ret = find_perf_probe_point((unsigned long)addr, pp);
+
+		dinfo = debuginfo__new_online_kernel(addr);
+		if (dinfo) {
+			ret = debuginfo__find_probe_point(dinfo,
+						 (unsigned long)addr, pp);
+			debuginfo__delete(dinfo);
+		} else {
+			pr_debug("Failed to open debuginfo at 0x%" PRIx64 "\n",
+				 addr);
+			ret = -ENOENT;
+		}
 	}
 	if (ret <= 0) {
 		pr_debug("Failed to find corresponding probes from "
@@ -214,30 +237,70 @@ static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
 	return 0;
 }
 
+static int add_module_to_probe_trace_events(struct probe_trace_event *tevs,
+					    int ntevs, const char *module)
+{
+	int i, ret = 0;
+	char *tmp;
+
+	if (!module)
+		return 0;
+
+	tmp = strrchr(module, '/');
+	if (tmp) {
+		/* This is a module path -- get the module name */
+		module = strdup(tmp + 1);
+		if (!module)
+			return -ENOMEM;
+		tmp = strchr(module, '.');
+		if (tmp)
+			*tmp = '\0';
+		tmp = (char *)module;	/* For free() */
+	}
+
+	for (i = 0; i < ntevs; i++) {
+		tevs[i].point.module = strdup(module);
+		if (!tevs[i].point.module) {
+			ret = -ENOMEM;
+			break;
+		}
+	}
+
+	if (tmp)
+		free(tmp);
+
+	return ret;
+}
+
 /* 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, const char *module)
+					  struct probe_trace_event **tevs,
+					  int max_tevs, const char *module)
 {
 	bool need_dwarf = perf_probe_event_need_dwarf(pev);
-	int fd, ntevs;
+	struct debuginfo *dinfo = open_debuginfo(module);
+	int ntevs, ret = 0;
 
-	fd = open_vmlinux(module);
-	if (fd < 0) {
+	if (!dinfo) {
 		if (need_dwarf) {
 			pr_warning("Failed to open debuginfo file.\n");
-			return fd;
+			return -ENOENT;
 		}
-		pr_debug("Could not open vmlinux. Try to use symbols.\n");
+		pr_debug("Could not open debuginfo. Try to use symbols.\n");
 		return 0;
 	}
 
-	/* Searching trace events corresponding to probe event */
-	ntevs = find_probe_trace_events(fd, pev, tevs, max_tevs);
+	/* Searching trace events corresponding to a probe event */
+	ntevs = debuginfo__find_trace_events(dinfo, pev, tevs, max_tevs);
+
+	debuginfo__delete(dinfo);
 
 	if (ntevs > 0) {	/* Succeeded to find trace events */
 		pr_debug("find %d probe_trace_events.\n", ntevs);
-		return ntevs;
+		if (module)
+			ret = add_module_to_probe_trace_events(*tevs, ntevs,
+							       module);
+		return ret < 0 ? ret : ntevs;
 	}
 
 	if (ntevs == 0)	{	/* No error but failed to find probe point. */
@@ -371,8 +434,9 @@ int show_line_range(struct line_range *lr, const char *module)
 {
 	int l = 1;
 	struct line_node *ln;
+	struct debuginfo *dinfo;
 	FILE *fp;
-	int fd, ret;
+	int ret;
 	char *tmp;
 
 	/* Search a line range */
@@ -380,13 +444,14 @@ int show_line_range(struct line_range *lr, const char *module)
 	if (ret < 0)
 		return ret;
 
-	fd = open_vmlinux(module);
-	if (fd < 0) {
+	dinfo = open_debuginfo(module);
+	if (!dinfo) {
 		pr_warning("Failed to open debuginfo file.\n");
-		return fd;
+		return -ENOENT;
 	}
 
-	ret = find_line_range(fd, lr);
+	ret = debuginfo__find_line_range(dinfo, lr);
+	debuginfo__delete(dinfo);
 	if (ret == 0) {
 		pr_warning("Specified source line is not found.\n");
 		return -ENOENT;
@@ -448,7 +513,8 @@ end:
 	return ret;
 }
 
-static int show_available_vars_at(int fd, struct perf_probe_event *pev,
+static int show_available_vars_at(struct debuginfo *dinfo,
+				  struct perf_probe_event *pev,
 				  int max_vls, struct strfilter *_filter,
 				  bool externs)
 {
@@ -463,7 +529,8 @@ static int show_available_vars_at(int fd, struct perf_probe_event *pev,
 		return -EINVAL;
 	pr_debug("Searching variables at %s\n", buf);
 
-	ret = find_available_vars_at(fd, pev, &vls, max_vls, externs);
+	ret = debuginfo__find_available_vars_at(dinfo, pev, &vls,
+						max_vls, externs);
 	if (ret <= 0) {
 		pr_err("Failed to find variables at %s (%d)\n", buf, ret);
 		goto end;
@@ -504,24 +571,26 @@ int show_available_vars(struct perf_probe_event *pevs, int npevs,
 			int max_vls, const char *module,
 			struct strfilter *_filter, bool externs)
 {
-	int i, fd, ret = 0;
+	int i, ret = 0;
+	struct debuginfo *dinfo;
 
 	ret = init_vmlinux();
 	if (ret < 0)
 		return ret;
 
+	dinfo = open_debuginfo(module);
+	if (!dinfo) {
+		pr_warning("Failed to open debuginfo file.\n");
+		return -ENOENT;
+	}
+
 	setup_pager();
 
-	for (i = 0; i < npevs && ret >= 0; i++) {
-		fd = open_vmlinux(module);
-		if (fd < 0) {
-			pr_warning("Failed to open debug information file.\n");
-			ret = fd;
-			break;
-		}
-		ret = show_available_vars_at(fd, &pevs[i], max_vls, _filter,
+	for (i = 0; i < npevs && ret >= 0; i++)
+		ret = show_available_vars_at(dinfo, &pevs[i], max_vls, _filter,
 					     externs);
-	}
+
+	debuginfo__delete(dinfo);
 	return ret;
 }
 
@@ -990,7 +1059,7 @@ bool perf_probe_event_need_dwarf(struct perf_probe_event *pev)
 
 /* Parse probe_events event into struct probe_point */
 static int parse_probe_trace_command(const char *cmd,
-					struct probe_trace_event *tev)
+				     struct probe_trace_event *tev)
 {
 	struct probe_trace_point *tp = &tev->point;
 	char pr;
@@ -1023,8 +1092,14 @@ static int parse_probe_trace_command(const char *cmd,
 
 	tp->retprobe = (pr == 'r');
 
-	/* Scan function name and offset */
-	ret = sscanf(argv[1], "%a[^+]+%lu", (float *)(void *)&tp->symbol,
+	/* Scan module name(if there), function name and offset */
+	p = strchr(argv[1], ':');
+	if (p) {
+		tp->module = strndup(argv[1], p - argv[1]);
+		p++;
+	} else
+		p = argv[1];
+	ret = sscanf(p, "%a[^+]+%lu", (float *)(void *)&tp->symbol,
 		     &tp->offset);
 	if (ret == 1)
 		tp->offset = 0;
@@ -1269,9 +1344,10 @@ char *synthesize_probe_trace_command(struct probe_trace_event *tev)
 	if (buf == NULL)
 		return NULL;
 
-	len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s %s+%lu",
+	len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s %s%s%s+%lu",
 			 tp->retprobe ? 'r' : 'p',
 			 tev->group, tev->event,
+			 tp->module ?: "", tp->module ? ":" : "",
 			 tp->symbol, tp->offset);
 	if (len <= 0)
 		goto error;
@@ -1378,6 +1454,8 @@ static void clear_probe_trace_event(struct probe_trace_event *tev)
 		free(tev->group);
 	if (tev->point.symbol)
 		free(tev->point.symbol);
+	if (tev->point.module)
+		free(tev->point.module);
 	for (i = 0; i < tev->nargs; i++) {
 		if (tev->args[i].name)
 			free(tev->args[i].name);
@@ -1729,7 +1807,7 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev,
 	/* Convert perf_probe_event with debuginfo */
 	ret = try_to_find_probe_trace_events(pev, tevs, max_tevs, module);
 	if (ret != 0)
-		return ret;
+		return ret;	/* Found in debuginfo or got an error */
 
 	/* Allocate trace event buffer */
 	tev = *tevs = zalloc(sizeof(struct probe_trace_event));
@@ -1742,6 +1820,11 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev,
 		ret = -ENOMEM;
 		goto error;
 	}
+	tev->point.module = strdup(module);
+	if (tev->point.module == NULL) {
+		ret = -ENOMEM;
+		goto error;
+	}
 	tev->point.offset = pev->point.offset;
 	tev->point.retprobe = pev->point.retprobe;
 	tev->nargs = pev->nargs;
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index 3434fc9d79d..a7dee835f49 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -10,6 +10,7 @@ extern bool probe_event_dry_run;
 /* kprobe-tracer tracing point */
 struct probe_trace_point {
 	char		*symbol;	/* Base symbol */
+	char		*module;	/* Module name */
 	unsigned long	offset;		/* Offset from symbol */
 	bool		retprobe;	/* Return probe flag */
 };
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 3b9d0b800d5..3e44a3e3651 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -43,21 +43,6 @@
 /* Kprobe tracer basic type is up to u64 */
 #define MAX_BASIC_TYPE_BITS	64
 
-/*
- * Compare the tail of two strings.
- * Return 0 if whole of either string is same as another's tail part.
- */
-static int strtailcmp(const char *s1, const char *s2)
-{
-	int i1 = strlen(s1);
-	int i2 = strlen(s2);
-	while (--i1 >= 0 && --i2 >= 0) {
-		if (s1[i1] != s2[i2])
-			return s1[i1] - s2[i2];
-	}
-	return 0;
-}
-
 /* Line number list operations */
 
 /* Add a line to line number list */
@@ -131,29 +116,37 @@ static const Dwfl_Callbacks offline_callbacks = {
 };
 
 /* Get a Dwarf from offline image */
-static Dwarf *dwfl_init_offline_dwarf(int fd, Dwfl **dwflp, Dwarf_Addr *bias)
+static int debuginfo__init_offline_dwarf(struct debuginfo *self,
+					 const char *path)
 {
 	Dwfl_Module *mod;
-	Dwarf *dbg = NULL;
+	int fd;
 
-	if (!dwflp)
-		return NULL;
+	fd = open(path, O_RDONLY);
+	if (fd < 0)
+		return fd;
 
-	*dwflp = dwfl_begin(&offline_callbacks);
-	if (!*dwflp)
-		return NULL;
+	self->dwfl = dwfl_begin(&offline_callbacks);
+	if (!self->dwfl)
+		goto error;
 
-	mod = dwfl_report_offline(*dwflp, "", "", fd);
+	mod = dwfl_report_offline(self->dwfl, "", "", fd);
 	if (!mod)
 		goto error;
 
-	dbg = dwfl_module_getdwarf(mod, bias);
-	if (!dbg) {
+	self->dbg = dwfl_module_getdwarf(mod, &self->bias);
+	if (!self->dbg)
+		goto error;
+
+	return 0;
 error:
-		dwfl_end(*dwflp);
-		*dwflp = NULL;
-	}
-	return dbg;
+	if (self->dwfl)
+		dwfl_end(self->dwfl);
+	else
+		close(fd);
+	memset(self, 0, sizeof(*self));
+
+	return -ENOENT;
 }
 
 #if _ELFUTILS_PREREQ(0, 148)
@@ -189,597 +182,81 @@ static const Dwfl_Callbacks kernel_callbacks = {
 };
 
 /* Get a Dwarf from live kernel image */
-static Dwarf *dwfl_init_live_kernel_dwarf(Dwarf_Addr addr, Dwfl **dwflp,
-					  Dwarf_Addr *bias)
+static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self,
+					       Dwarf_Addr addr)
 {
-	Dwarf *dbg;
-
-	if (!dwflp)
-		return NULL;
-
-	*dwflp = dwfl_begin(&kernel_callbacks);
-	if (!*dwflp)
-		return NULL;
+	self->dwfl = dwfl_begin(&kernel_callbacks);
+	if (!self->dwfl)
+		return -EINVAL;
 
 	/* Load the kernel dwarves: Don't care the result here */
-	dwfl_linux_kernel_report_kernel(*dwflp);
-	dwfl_linux_kernel_report_modules(*dwflp);
+	dwfl_linux_kernel_report_kernel(self->dwfl);
+	dwfl_linux_kernel_report_modules(self->dwfl);
 
-	dbg = dwfl_addrdwarf(*dwflp, addr, bias);
+	self->dbg = dwfl_addrdwarf(self->dwfl, addr, &self->bias);
 	/* Here, check whether we could get a real dwarf */
-	if (!dbg) {
+	if (!self->dbg) {
 		pr_debug("Failed to find kernel dwarf at %lx\n",
 			 (unsigned long)addr);
-		dwfl_end(*dwflp);
-		*dwflp = NULL;
+		dwfl_end(self->dwfl);
+		memset(self, 0, sizeof(*self));
+		return -ENOENT;
 	}
-	return dbg;
+
+	return 0;
 }
 #else
 /* With older elfutils, this just support kernel module... */
-static Dwarf *dwfl_init_live_kernel_dwarf(Dwarf_Addr addr __used, Dwfl **dwflp,
-					  Dwarf_Addr *bias)
+static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self,
+					       Dwarf_Addr addr __used)
 {
-	int fd;
 	const char *path = kernel_get_module_path("kernel");
 
 	if (!path) {
 		pr_err("Failed to find vmlinux path\n");
-		return NULL;
+		return -ENOENT;
 	}
 
 	pr_debug2("Use file %s for debuginfo\n", path);
-	fd = open(path, O_RDONLY);
-	if (fd < 0)
-		return NULL;
-
-	return dwfl_init_offline_dwarf(fd, dwflp, bias);
+	return debuginfo__init_offline_dwarf(self, path);
 }
 #endif
 
-/* Dwarf wrappers */
-
-/* Find the realpath of the target file. */
-static const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname)
-{
-	Dwarf_Files *files;
-	size_t nfiles, i;
-	const char *src = NULL;
-	int ret;
-
-	if (!fname)
-		return NULL;
-
-	ret = dwarf_getsrcfiles(cu_die, &files, &nfiles);
-	if (ret != 0)
-		return NULL;
-
-	for (i = 0; i < nfiles; i++) {
-		src = dwarf_filesrc(files, i, NULL, NULL);
-		if (strtailcmp(src, fname) == 0)
-			break;
-	}
-	if (i == nfiles)
-		return NULL;
-	return src;
-}
-
-/* Get DW_AT_comp_dir (should be NULL with older gcc) */
-static const char *cu_get_comp_dir(Dwarf_Die *cu_die)
-{
-	Dwarf_Attribute attr;
-	if (dwarf_attr(cu_die, DW_AT_comp_dir, &attr) == NULL)
-		return NULL;
-	return dwarf_formstring(&attr);
-}
-
-/* Get a line number and file name for given address */
-static int cu_find_lineinfo(Dwarf_Die *cudie, unsigned long addr,
-			    const char **fname, int *lineno)
-{
-	Dwarf_Line *line;
-	Dwarf_Addr laddr;
-
-	line = dwarf_getsrc_die(cudie, (Dwarf_Addr)addr);
-	if (line && dwarf_lineaddr(line, &laddr) == 0 &&
-	    addr == (unsigned long)laddr && dwarf_lineno(line, lineno) == 0) {
-		*fname = dwarf_linesrc(line, NULL, NULL);
-		if (!*fname)
-			/* line number is useless without filename */
-			*lineno = 0;
-	}
-
-	return *lineno ?: -ENOENT;
-}
-
-/* Compare diename and tname */
-static bool die_compare_name(Dwarf_Die *dw_die, const char *tname)
-{
-	const char *name;
-	name = dwarf_diename(dw_die);
-	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)
-{
-	Dwarf_Attribute attr;
-
-	if (dwarf_attr_integrate(vr_die, DW_AT_type, &attr) &&
-	    dwarf_formref_die(&attr, die_mem))
-		return die_mem;
-	else
-		return NULL;
-}
-
-/* Get a type die, but skip qualifiers */
-static Dwarf_Die *__die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
-{
-	int tag;
-
-	do {
-		vr_die = die_get_type(vr_die, die_mem);
-		if (!vr_die)
-			break;
-		tag = dwarf_tag(vr_die);
-	} while (tag == DW_TAG_const_type ||
-		 tag == DW_TAG_restrict_type ||
-		 tag == DW_TAG_volatile_type ||
-		 tag == DW_TAG_shared_type);
-
-	return vr_die;
-}
-
-/* Get a type die, but skip qualifiers and typedef */
-static Dwarf_Die *die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
-{
-	do {
-		vr_die = __die_get_real_type(vr_die, die_mem);
-	} while (vr_die && dwarf_tag(vr_die) == DW_TAG_typedef);
-
-	return vr_die;
-}
-
-static int die_get_attr_udata(Dwarf_Die *tp_die, unsigned int attr_name,
-			      Dwarf_Word *result)
-{
-	Dwarf_Attribute attr;
-
-	if (dwarf_attr(tp_die, attr_name, &attr) == NULL ||
-	    dwarf_formudata(&attr, result) != 0)
-		return -ENOENT;
-
-	return 0;
-}
-
-static bool die_is_signed_type(Dwarf_Die *tp_die)
-{
-	Dwarf_Word ret;
-
-	if (die_get_attr_udata(tp_die, DW_AT_encoding, &ret))
-		return false;
-
-	return (ret == DW_ATE_signed_char || ret == DW_ATE_signed ||
-		ret == DW_ATE_signed_fixed);
-}
-
-static int die_get_byte_size(Dwarf_Die *tp_die)
-{
-	Dwarf_Word ret;
-
-	if (die_get_attr_udata(tp_die, DW_AT_byte_size, &ret))
-		return 0;
-
-	return (int)ret;
-}
-
-static int die_get_bit_size(Dwarf_Die *tp_die)
-{
-	Dwarf_Word ret;
-
-	if (die_get_attr_udata(tp_die, DW_AT_bit_size, &ret))
-		return 0;
-
-	return (int)ret;
-}
-
-static int die_get_bit_offset(Dwarf_Die *tp_die)
-{
-	Dwarf_Word ret;
-
-	if (die_get_attr_udata(tp_die, DW_AT_bit_offset, &ret))
-		return 0;
-
-	return (int)ret;
-}
-
-/* Get data_member_location offset */
-static int die_get_data_member_location(Dwarf_Die *mb_die, Dwarf_Word *offs)
-{
-	Dwarf_Attribute attr;
-	Dwarf_Op *expr;
-	size_t nexpr;
-	int ret;
-
-	if (dwarf_attr(mb_die, DW_AT_data_member_location, &attr) == NULL)
-		return -ENOENT;
-
-	if (dwarf_formudata(&attr, offs) != 0) {
-		/* DW_AT_data_member_location should be DW_OP_plus_uconst */
-		ret = dwarf_getlocation(&attr, &expr, &nexpr);
-		if (ret < 0 || nexpr == 0)
-			return -ENOENT;
-
-		if (expr[0].atom != DW_OP_plus_uconst || nexpr != 1) {
-			pr_debug("Unable to get offset:Unexpected OP %x (%zd)\n",
-				 expr[0].atom, nexpr);
-			return -ENOTSUP;
-		}
-		*offs = (Dwarf_Word)expr[0].number;
-	}
-	return 0;
-}
-
-/* Return values for die_find callbacks */
-enum {
-	DIE_FIND_CB_FOUND = 0,		/* End of Search */
-	DIE_FIND_CB_CHILD = 1,		/* Search only children */
-	DIE_FIND_CB_SIBLING = 2,	/* Search only siblings */
-	DIE_FIND_CB_CONTINUE = 3,	/* Search children and siblings */
-};
-
-/* Search a child die */
-static Dwarf_Die *die_find_child(Dwarf_Die *rt_die,
-				 int (*callback)(Dwarf_Die *, void *),
-				 void *data, Dwarf_Die *die_mem)
+struct debuginfo *debuginfo__new(const char *path)
 {
-	Dwarf_Die child_die;
-	int ret;
-
-	ret = dwarf_child(rt_die, die_mem);
-	if (ret != 0)
+	struct debuginfo *self = zalloc(sizeof(struct debuginfo));
+	if (!self)
 		return NULL;
 
-	do {
-		ret = callback(die_mem, data);
-		if (ret == DIE_FIND_CB_FOUND)
-			return die_mem;
-
-		if ((ret & DIE_FIND_CB_CHILD) &&
-		    die_find_child(die_mem, callback, data, &child_die)) {
-			memcpy(die_mem, &child_die, sizeof(Dwarf_Die));
-			return die_mem;
-		}
-	} while ((ret & DIE_FIND_CB_SIBLING) &&
-		 dwarf_siblingof(die_mem, die_mem) == 0);
-
-	return NULL;
-}
-
-struct __addr_die_search_param {
-	Dwarf_Addr	addr;
-	Dwarf_Die	*die_mem;
-};
-
-static int __die_search_func_cb(Dwarf_Die *fn_die, void *data)
-{
-	struct __addr_die_search_param *ad = data;
-
-	if (dwarf_tag(fn_die) == DW_TAG_subprogram &&
-	    dwarf_haspc(fn_die, ad->addr)) {
-		memcpy(ad->die_mem, fn_die, sizeof(Dwarf_Die));
-		return DWARF_CB_ABORT;
+	if (debuginfo__init_offline_dwarf(self, path) < 0) {
+		free(self);
+		self = NULL;
 	}
-	return DWARF_CB_OK;
-}
-
-/* Search a real subprogram including this line, */
-static Dwarf_Die *die_find_real_subprogram(Dwarf_Die *cu_die, Dwarf_Addr addr,
-					   Dwarf_Die *die_mem)
-{
-	struct __addr_die_search_param ad;
-	ad.addr = addr;
-	ad.die_mem = die_mem;
-	/* dwarf_getscopes can't find subprogram. */
-	if (!dwarf_getfuncs(cu_die, __die_search_func_cb, &ad, 0))
-		return NULL;
-	else
-		return die_mem;
-}
-
-/* die_find callback for inline function search */
-static int __die_find_inline_cb(Dwarf_Die *die_mem, void *data)
-{
-	Dwarf_Addr *addr = data;
-
-	if (dwarf_tag(die_mem) == DW_TAG_inlined_subroutine &&
-	    dwarf_haspc(die_mem, *addr))
-		return DIE_FIND_CB_FOUND;
 
-	return DIE_FIND_CB_CONTINUE;
+	return self;
 }
 
-/* Similar to dwarf_getfuncs, but returns inlined_subroutine if exists. */
-static Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
-				      Dwarf_Die *die_mem)
+struct debuginfo *debuginfo__new_online_kernel(unsigned long addr)
 {
-	Dwarf_Die tmp_die;
-
-	sp_die = die_find_child(sp_die, __die_find_inline_cb, &addr, &tmp_die);
-	if (!sp_die)
+	struct debuginfo *self = zalloc(sizeof(struct debuginfo));
+	if (!self)
 		return NULL;
 
-	/* Inlined function could be recursive. Trace it until fail */
-	while (sp_die) {
-		memcpy(die_mem, sp_die, sizeof(Dwarf_Die));
-		sp_die = die_find_child(sp_die, __die_find_inline_cb, &addr,
-					&tmp_die);
-	}
-
-	return 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 {
-	const char *fname;
-	line_walk_handler_t handler;
-	void *data;
-	int retval;
-};
-
-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)
-{
-	struct __line_walk_param lw = {
-		.handler = handler,
-		.data = data,
-		.retval = 0,
-	};
-	Dwarf_Die die_mem;
-	Dwarf_Addr addr;
-	int lineno;
-
-	/* Handle function declaration line */
-	lw.fname = dwarf_decl_file(sp_die);
-	if (lw.fname && dwarf_decl_line(sp_die, &lineno) == 0 &&
-	    dwarf_entrypc(sp_die, &addr) == 0) {
-		lw.retval = handler(lw.fname, lineno, addr, data);
-		if (lw.retval != 0)
-			goto done;
-	}
-	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)
-{
-	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;
+	if (debuginfo__init_online_kernel_dwarf(self, (Dwarf_Addr)addr) < 0) {
+		free(self);
+		self = NULL;
 	}
 
-	return ret;
-}
-
-struct __find_variable_param {
-	const char *name;
-	Dwarf_Addr addr;
-};
-
-static int __die_find_variable_cb(Dwarf_Die *die_mem, void *data)
-{
-	struct __find_variable_param *fvp = data;
-	int tag;
-
-	tag = dwarf_tag(die_mem);
-	if ((tag == DW_TAG_formal_parameter ||
-	     tag == DW_TAG_variable) &&
-	    die_compare_name(die_mem, fvp->name))
-		return DIE_FIND_CB_FOUND;
-
-	if (dwarf_haspc(die_mem, fvp->addr))
-		return DIE_FIND_CB_CONTINUE;
-	else
-		return DIE_FIND_CB_SIBLING;
-}
-
-/* Find a variable called 'name' at given address */
-static Dwarf_Die *die_find_variable_at(Dwarf_Die *sp_die, const char *name,
-				       Dwarf_Addr addr, Dwarf_Die *die_mem)
-{
-	struct __find_variable_param fvp = { .name = name, .addr = addr};
-
-	return die_find_child(sp_die, __die_find_variable_cb, (void *)&fvp,
-			      die_mem);
-}
-
-static int __die_find_member_cb(Dwarf_Die *die_mem, void *data)
-{
-	const char *name = data;
-
-	if ((dwarf_tag(die_mem) == DW_TAG_member) &&
-	    die_compare_name(die_mem, name))
-		return DIE_FIND_CB_FOUND;
-
-	return DIE_FIND_CB_SIBLING;
-}
-
-/* Find a member called 'name' */
-static Dwarf_Die *die_find_member(Dwarf_Die *st_die, const char *name,
-				  Dwarf_Die *die_mem)
-{
-	return die_find_child(st_die, __die_find_member_cb, (void *)name,
-			      die_mem);
-}
-
-/* Get the name of given variable DIE */
-static int die_get_typename(Dwarf_Die *vr_die, char *buf, int len)
-{
-	Dwarf_Die type;
-	int tag, ret, ret2;
-	const char *tmp = "";
-
-	if (__die_get_real_type(vr_die, &type) == NULL)
-		return -ENOENT;
-
-	tag = dwarf_tag(&type);
-	if (tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)
-		tmp = "*";
-	else if (tag == DW_TAG_subroutine_type) {
-		/* Function pointer */
-		ret = snprintf(buf, len, "(function_type)");
-		return (ret >= len) ? -E2BIG : ret;
-	} else {
-		if (!dwarf_diename(&type))
-			return -ENOENT;
-		if (tag == DW_TAG_union_type)
-			tmp = "union ";
-		else if (tag == DW_TAG_structure_type)
-			tmp = "struct ";
-		/* Write a base name */
-		ret = snprintf(buf, len, "%s%s", tmp, dwarf_diename(&type));
-		return (ret >= len) ? -E2BIG : ret;
-	}
-	ret = die_get_typename(&type, buf, len);
-	if (ret > 0) {
-		ret2 = snprintf(buf + ret, len - ret, "%s", tmp);
-		ret = (ret2 >= len - ret) ? -E2BIG : ret2 + ret;
-	}
-	return ret;
+	return self;
 }
 
-/* Get the name and type of given variable DIE, stored as "type\tname" */
-static int die_get_varname(Dwarf_Die *vr_die, char *buf, int len)
+void debuginfo__delete(struct debuginfo *self)
 {
-	int ret, ret2;
-
-	ret = die_get_typename(vr_die, buf, len);
-	if (ret < 0) {
-		pr_debug("Failed to get type, make it unknown.\n");
-		ret = snprintf(buf, len, "(unknown_type)");
+	if (self) {
+		if (self->dwfl)
+			dwfl_end(self->dwfl);
+		free(self);
 	}
-	if (ret > 0) {
-		ret2 = snprintf(buf + ret, len - ret, "\t%s",
-				dwarf_diename(vr_die));
-		ret = (ret2 >= len - ret) ? -E2BIG : ret2 + ret;
-	}
-	return ret;
 }
 
 /*
@@ -897,6 +374,7 @@ static int convert_variable_type(Dwarf_Die *vr_die,
 	struct probe_trace_arg_ref **ref_ptr = &tvar->ref;
 	Dwarf_Die type;
 	char buf[16];
+	int bsize, boffs, total;
 	int ret;
 
 	/* TODO: check all types */
@@ -906,11 +384,15 @@ static int convert_variable_type(Dwarf_Die *vr_die,
 		return (tvar->type == NULL) ? -ENOMEM : 0;
 	}
 
-	if (die_get_bit_size(vr_die) != 0) {
+	bsize = dwarf_bitsize(vr_die);
+	if (bsize > 0) {
 		/* This is a bitfield */
-		ret = snprintf(buf, 16, "b%d@%d/%zd", die_get_bit_size(vr_die),
-				die_get_bit_offset(vr_die),
-				BYTES_TO_BITS(die_get_byte_size(vr_die)));
+		boffs = dwarf_bitoffset(vr_die);
+		total = dwarf_bytesize(vr_die);
+		if (boffs < 0 || total < 0)
+			return -ENOENT;
+		ret = snprintf(buf, 16, "b%d@%d/%zd", bsize, boffs,
+				BYTES_TO_BITS(total));
 		goto formatted;
 	}
 
@@ -958,10 +440,11 @@ static int convert_variable_type(Dwarf_Die *vr_die,
 		return (tvar->type == NULL) ? -ENOMEM : 0;
 	}
 
-	ret = BYTES_TO_BITS(die_get_byte_size(&type));
-	if (!ret)
+	ret = dwarf_bytesize(&type);
+	if (ret <= 0)
 		/* No size ... try to use default type */
 		return 0;
+	ret = BYTES_TO_BITS(ret);
 
 	/* Check the bitwidth */
 	if (ret > MAX_BASIC_TYPE_BITS) {
@@ -1025,7 +508,7 @@ static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
 			else
 				*ref_ptr = ref;
 		}
-		ref->offset += die_get_byte_size(&type) * field->index;
+		ref->offset += dwarf_bytesize(&type) * field->index;
 		if (!field->next)
 			/* Save vr_die for converting types */
 			memcpy(die_mem, vr_die, sizeof(*die_mem));
@@ -1245,8 +728,7 @@ static int call_probe_finder(Dwarf_Die *sp_die, struct probe_finder *pf)
 
 	/* If no real subprogram, find a real one */
 	if (!sp_die || dwarf_tag(sp_die) != DW_TAG_subprogram) {
-		sp_die = die_find_real_subprogram(&pf->cu_die,
-						  pf->addr, &die_mem);
+		sp_die = die_find_realfunc(&pf->cu_die, pf->addr, &die_mem);
 		if (!sp_die) {
 			pr_warning("Failed to find probe point in any "
 				   "functions.\n");
@@ -1504,28 +986,18 @@ static int pubname_search_cb(Dwarf *dbg, Dwarf_Global *gl, void *data)
 }
 
 /* Find probe points from debuginfo */
-static int find_probes(int fd, struct probe_finder *pf)
+static int debuginfo__find_probes(struct debuginfo *self,
+				  struct probe_finder *pf)
 {
 	struct perf_probe_point *pp = &pf->pev->point;
 	Dwarf_Off off, noff;
 	size_t cuhl;
 	Dwarf_Die *diep;
-	Dwarf *dbg = NULL;
-	Dwfl *dwfl;
-	Dwarf_Addr bias;	/* Currently ignored */
 	int ret = 0;
 
-	dbg = dwfl_init_offline_dwarf(fd, &dwfl, &bias);
-	if (!dbg) {
-		pr_warning("No debug information found in the vmlinux - "
-			"please rebuild with CONFIG_DEBUG_INFO=y.\n");
-		close(fd);	/* Without dwfl_end(), fd isn't closed. */
-		return -EBADF;
-	}
-
 #if _ELFUTILS_PREREQ(0, 142)
 	/* Get the call frame information from this dwarf */
-	pf->cfi = dwarf_getcfi(dbg);
+	pf->cfi = dwarf_getcfi(self->dbg);
 #endif
 
 	off = 0;
@@ -1544,7 +1016,8 @@ static int find_probes(int fd, struct probe_finder *pf)
 			.data = pf,
 		};
 
-		dwarf_getpubnames(dbg, pubname_search_cb, &pubname_param, 0);
+		dwarf_getpubnames(self->dbg, pubname_search_cb,
+				  &pubname_param, 0);
 		if (pubname_param.found) {
 			ret = probe_point_search_cb(&pf->sp_die, &probe_param);
 			if (ret)
@@ -1553,9 +1026,9 @@ static int find_probes(int fd, struct probe_finder *pf)
 	}
 
 	/* Loop on CUs (Compilation Unit) */
-	while (!dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL)) {
+	while (!dwarf_nextcu(self->dbg, off, &noff, &cuhl, NULL, NULL, NULL)) {
 		/* Get the DIE(Debugging Information Entry) of this CU */
-		diep = dwarf_offdie(dbg, off + cuhl, &pf->cu_die);
+		diep = dwarf_offdie(self->dbg, off + cuhl, &pf->cu_die);
 		if (!diep)
 			continue;
 
@@ -1582,8 +1055,6 @@ static int find_probes(int fd, struct probe_finder *pf)
 
 found:
 	line_list__free(&pf->lcache);
-	if (dwfl)
-		dwfl_end(dwfl);
 
 	return ret;
 }
@@ -1629,8 +1100,9 @@ static int add_probe_trace_event(Dwarf_Die *sp_die, struct probe_finder *pf)
 }
 
 /* Find probe_trace_events specified by perf_probe_event from debuginfo */
-int find_probe_trace_events(int fd, struct perf_probe_event *pev,
-			    struct probe_trace_event **tevs, int max_tevs)
+int debuginfo__find_trace_events(struct debuginfo *self,
+				 struct perf_probe_event *pev,
+				 struct probe_trace_event **tevs, int max_tevs)
 {
 	struct trace_event_finder tf = {
 			.pf = {.pev = pev, .callback = add_probe_trace_event},
@@ -1645,7 +1117,7 @@ int find_probe_trace_events(int fd, struct perf_probe_event *pev,
 	tf.tevs = *tevs;
 	tf.ntevs = 0;
 
-	ret = find_probes(fd, &tf.pf);
+	ret = debuginfo__find_probes(self, &tf.pf);
 	if (ret < 0) {
 		free(*tevs);
 		*tevs = NULL;
@@ -1739,9 +1211,10 @@ out:
 }
 
 /* Find available variables at given probe point */
-int find_available_vars_at(int fd, struct perf_probe_event *pev,
-			   struct variable_list **vls, int max_vls,
-			   bool externs)
+int debuginfo__find_available_vars_at(struct debuginfo *self,
+				      struct perf_probe_event *pev,
+				      struct variable_list **vls,
+				      int max_vls, bool externs)
 {
 	struct available_var_finder af = {
 			.pf = {.pev = pev, .callback = add_available_vars},
@@ -1756,7 +1229,7 @@ int find_available_vars_at(int fd, struct perf_probe_event *pev,
 	af.vls = *vls;
 	af.nvls = 0;
 
-	ret = find_probes(fd, &af.pf);
+	ret = debuginfo__find_probes(self, &af.pf);
 	if (ret < 0) {
 		/* Free vlist for error */
 		while (af.nvls--) {
@@ -1774,28 +1247,19 @@ int find_available_vars_at(int fd, struct perf_probe_event *pev,
 }
 
 /* Reverse search */
-int find_perf_probe_point(unsigned long addr, struct perf_probe_point *ppt)
+int debuginfo__find_probe_point(struct debuginfo *self, unsigned long addr,
+				struct perf_probe_point *ppt)
 {
 	Dwarf_Die cudie, spdie, indie;
-	Dwarf *dbg = NULL;
-	Dwfl *dwfl = NULL;
-	Dwarf_Addr _addr, baseaddr, bias = 0;
+	Dwarf_Addr _addr, baseaddr;
 	const char *fname = NULL, *func = NULL, *tmp;
 	int baseline = 0, lineno = 0, ret = 0;
 
-	/* Open the live linux kernel */
-	dbg = dwfl_init_live_kernel_dwarf(addr, &dwfl, &bias);
-	if (!dbg) {
-		pr_warning("No debug information found in the vmlinux - "
-			"please rebuild with CONFIG_DEBUG_INFO=y.\n");
-		ret = -EINVAL;
-		goto end;
-	}
-
 	/* Adjust address with bias */
-	addr += bias;
+	addr += self->bias;
+
 	/* Find cu die */
-	if (!dwarf_addrdie(dbg, (Dwarf_Addr)addr - bias, &cudie)) {
+	if (!dwarf_addrdie(self->dbg, (Dwarf_Addr)addr - self->bias, &cudie)) {
 		pr_warning("Failed to find debug information for address %lx\n",
 			   addr);
 		ret = -EINVAL;
@@ -1807,7 +1271,7 @@ int find_perf_probe_point(unsigned long addr, struct perf_probe_point *ppt)
 	/* Don't care whether it failed or not */
 
 	/* Find a corresponding function (name, baseline and baseaddr) */
-	if (die_find_real_subprogram(&cudie, (Dwarf_Addr)addr, &spdie)) {
+	if (die_find_realfunc(&cudie, (Dwarf_Addr)addr, &spdie)) {
 		/* Get function entry information */
 		tmp = dwarf_diename(&spdie);
 		if (!tmp ||
@@ -1871,8 +1335,6 @@ post:
 		}
 	}
 end:
-	if (dwfl)
-		dwfl_end(dwfl);
 	if (ret == 0 && (fname || func))
 		ret = 1;	/* Found a point */
 	return ret;
@@ -1982,26 +1444,15 @@ static int find_line_range_by_func(struct line_finder *lf)
 	return param.retval;
 }
 
-int find_line_range(int fd, struct line_range *lr)
+int debuginfo__find_line_range(struct debuginfo *self, struct line_range *lr)
 {
 	struct line_finder lf = {.lr = lr, .found = 0};
 	int ret = 0;
 	Dwarf_Off off = 0, noff;
 	size_t cuhl;
 	Dwarf_Die *diep;
-	Dwarf *dbg = NULL;
-	Dwfl *dwfl;
-	Dwarf_Addr bias;	/* Currently ignored */
 	const char *comp_dir;
 
-	dbg = dwfl_init_offline_dwarf(fd, &dwfl, &bias);
-	if (!dbg) {
-		pr_warning("No debug information found in the vmlinux - "
-			"please rebuild with CONFIG_DEBUG_INFO=y.\n");
-		close(fd);	/* Without dwfl_end(), fd isn't closed. */
-		return -EBADF;
-	}
-
 	/* Fastpath: lookup by function name from .debug_pubnames section */
 	if (lr->function) {
 		struct pubname_callback_param pubname_param = {
@@ -2010,7 +1461,8 @@ int find_line_range(int fd, struct line_range *lr)
 		struct dwarf_callback_param line_range_param = {
 			.data = (void *)&lf, .retval = 0};
 
-		dwarf_getpubnames(dbg, pubname_search_cb, &pubname_param, 0);
+		dwarf_getpubnames(self->dbg, pubname_search_cb,
+				  &pubname_param, 0);
 		if (pubname_param.found) {
 			line_range_search_cb(&lf.sp_die, &line_range_param);
 			if (lf.found)
@@ -2020,11 +1472,12 @@ int find_line_range(int fd, struct line_range *lr)
 
 	/* Loop on CUs (Compilation Unit) */
 	while (!lf.found && ret >= 0) {
-		if (dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL) != 0)
+		if (dwarf_nextcu(self->dbg, off, &noff, &cuhl,
+				 NULL, NULL, NULL) != 0)
 			break;
 
 		/* Get the DIE(Debugging Information Entry) of this CU */
-		diep = dwarf_offdie(dbg, off + cuhl, &lf.cu_die);
+		diep = dwarf_offdie(self->dbg, off + cuhl, &lf.cu_die);
 		if (!diep)
 			continue;
 
@@ -2058,7 +1511,6 @@ found:
 	}
 
 	pr_debug("path: %s\n", lr->path);
-	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 605730a366d..c478b42a247 100644
--- a/tools/perf/util/probe-finder.h
+++ b/tools/perf/util/probe-finder.h
@@ -16,27 +16,42 @@ static inline int is_c_varname(const char *name)
 }
 
 #ifdef DWARF_SUPPORT
+
+#include "dwarf-aux.h"
+
+/* TODO: export debuginfo data structure even if no dwarf support */
+
+/* debug information structure */
+struct debuginfo {
+	Dwarf		*dbg;
+	Dwfl		*dwfl;
+	Dwarf_Addr	bias;
+};
+
+extern struct debuginfo *debuginfo__new(const char *path);
+extern struct debuginfo *debuginfo__new_online_kernel(unsigned long addr);
+extern void debuginfo__delete(struct debuginfo *self);
+
 /* Find probe_trace_events specified by perf_probe_event from debuginfo */
-extern int find_probe_trace_events(int fd, struct perf_probe_event *pev,
-				    struct probe_trace_event **tevs,
-				    int max_tevs);
+extern int debuginfo__find_trace_events(struct debuginfo *self,
+					struct perf_probe_event *pev,
+					struct probe_trace_event **tevs,
+					int max_tevs);
 
 /* Find a perf_probe_point from debuginfo */
-extern int find_perf_probe_point(unsigned long addr,
-				 struct perf_probe_point *ppt);
+extern int debuginfo__find_probe_point(struct debuginfo *self,
+				       unsigned long addr,
+				       struct perf_probe_point *ppt);
 
 /* Find a line range */
-extern int find_line_range(int fd, struct line_range *lr);
+extern int debuginfo__find_line_range(struct debuginfo *self,
+				      struct line_range *lr);
 
 /* Find available variables */
-extern int find_available_vars_at(int fd, struct perf_probe_event *pev,
-				  struct variable_list **vls, int max_points,
-				  bool externs);
-
-#include <dwarf.h>
-#include <elfutils/libdw.h>
-#include <elfutils/libdwfl.h>
-#include <elfutils/version.h>
+extern int debuginfo__find_available_vars_at(struct debuginfo *self,
+					     struct perf_probe_event *pev,
+					     struct variable_list **vls,
+					     int max_points, bool externs);
 
 struct probe_finder {
 	struct perf_probe_event	*pev;		/* Target probe event */
diff --git a/tools/perf/util/string.c b/tools/perf/util/string.c
index b9a985dadd0..d5836382ff2 100644
--- a/tools/perf/util/string.c
+++ b/tools/perf/util/string.c
@@ -294,3 +294,22 @@ bool strlazymatch(const char *str, const char *pat)
 {
 	return __match_glob(str, pat, true);
 }
+
+/**
+ * strtailcmp - Compare the tail of two strings
+ * @s1: 1st string to be compared
+ * @s2: 2nd string to be compared
+ *
+ * Return 0 if whole of either string is same as another's tail part.
+ */
+int strtailcmp(const char *s1, const char *s2)
+{
+	int i1 = strlen(s1);
+	int i2 = strlen(s2);
+	while (--i1 >= 0 && --i2 >= 0) {
+		if (s1[i1] != s2[i2])
+			return s1[i1] - s2[i2];
+	}
+	return 0;
+}
+
diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
index 35729f4c40c..3403f814ad7 100644
--- a/tools/perf/util/trace-event-info.c
+++ b/tools/perf/util/trace-event-info.c
@@ -183,106 +183,59 @@ int bigendian(void)
 	return *ptr == 0x01020304;
 }
 
-static unsigned long long copy_file_fd(int fd)
+/* unfortunately, you can not stat debugfs or proc files for size */
+static void record_file(const char *file, size_t hdr_sz)
 {
 	unsigned long long size = 0;
-	char buf[BUFSIZ];
-	int r;
-
-	do {
-		r = read(fd, buf, BUFSIZ);
-		if (r > 0) {
-			size += r;
-			write_or_die(buf, r);
-		}
-	} while (r > 0);
-
-	return size;
-}
-
-static unsigned long long copy_file(const char *file)
-{
-	unsigned long long size = 0;
-	int fd;
+	char buf[BUFSIZ], *sizep;
+	off_t hdr_pos = lseek(output_fd, 0, SEEK_CUR);
+	int r, fd;
 
 	fd = open(file, O_RDONLY);
 	if (fd < 0)
 		die("Can't read '%s'", file);
-	size = copy_file_fd(fd);
-	close(fd);
 
-	return size;
-}
-
-static unsigned long get_size_fd(int fd)
-{
-	unsigned long long size = 0;
-	char buf[BUFSIZ];
-	int r;
+	/* put in zeros for file size, then fill true size later */
+	write_or_die(&size, hdr_sz);
 
 	do {
 		r = read(fd, buf, BUFSIZ);
-		if (r > 0)
+		if (r > 0) {
 			size += r;
+			write_or_die(buf, r);
+		}
 	} while (r > 0);
-
-	lseek(fd, 0, SEEK_SET);
-
-	return size;
-}
-
-static unsigned long get_size(const char *file)
-{
-	unsigned long long size = 0;
-	int fd;
-
-	fd = open(file, O_RDONLY);
-	if (fd < 0)
-		die("Can't read '%s'", file);
-	size = get_size_fd(fd);
 	close(fd);
 
-	return size;
+	/* ugh, handle big-endian hdr_size == 4 */
+	sizep = (char*)&size;
+	if (bigendian())
+		sizep += sizeof(u64) - hdr_sz;
+
+	if (pwrite(output_fd, sizep, hdr_sz, hdr_pos) < 0)
+		die("writing to %s", output_file);
 }
 
 static void read_header_files(void)
 {
-	unsigned long long size, check_size;
 	char *path;
-	int fd;
+	struct stat st;
 
 	path = get_tracing_file("events/header_page");
-	fd = open(path, O_RDONLY);
-	if (fd < 0)
+	if (stat(path, &st) < 0)
 		die("can't read '%s'", path);
 
-	/* unfortunately, you can not stat debugfs files for size */
-	size = get_size_fd(fd);
-
 	write_or_die("header_page", 12);
-	write_or_die(&size, 8);
-	check_size = copy_file_fd(fd);
-	close(fd);
-
-	if (size != check_size)
-		die("wrong size for '%s' size=%lld read=%lld",
-		    path, size, check_size);
+	record_file(path, 8);
 	put_tracing_file(path);
 
 	path = get_tracing_file("events/header_event");
-	fd = open(path, O_RDONLY);
-	if (fd < 0)
+	if (stat(path, &st) < 0)
 		die("can't read '%s'", path);
 
-	size = get_size_fd(fd);
-
 	write_or_die("header_event", 13);
-	write_or_die(&size, 8);
-	check_size = copy_file_fd(fd);
-	if (size != check_size)
-		die("wrong size for '%s'", path);
+	record_file(path, 8);
 	put_tracing_file(path);
-	close(fd);
 }
 
 static bool name_in_tp_list(char *sys, struct tracepoint_path *tps)
@@ -298,7 +251,6 @@ static bool name_in_tp_list(char *sys, struct tracepoint_path *tps)
 
 static void copy_event_system(const char *sys, struct tracepoint_path *tps)
 {
-	unsigned long long size, check_size;
 	struct dirent *dent;
 	struct stat st;
 	char *format;
@@ -338,14 +290,8 @@ static void copy_event_system(const char *sys, struct tracepoint_path *tps)
 		sprintf(format, "%s/%s/format", sys, dent->d_name);
 		ret = stat(format, &st);
 
-		if (ret >= 0) {
-			/* unfortunately, you can not stat debugfs files for size */
-			size = get_size(format);
-			write_or_die(&size, 8);
-			check_size = copy_file(format);
-			if (size != check_size)
-				die("error in size of file '%s'", format);
-		}
+		if (ret >= 0)
+			record_file(format, 8);
 
 		free(format);
 	}
@@ -426,7 +372,7 @@ static void read_event_files(struct tracepoint_path *tps)
 
 static void read_proc_kallsyms(void)
 {
-	unsigned int size, check_size;
+	unsigned int size;
 	const char *path = "/proc/kallsyms";
 	struct stat st;
 	int ret;
@@ -438,17 +384,12 @@ static void read_proc_kallsyms(void)
 		write_or_die(&size, 4);
 		return;
 	}
-	size = get_size(path);
-	write_or_die(&size, 4);
-	check_size = copy_file(path);
-	if (size != check_size)
-		die("error in size of file '%s'", path);
-
+	record_file(path, 4);
 }
 
 static void read_ftrace_printk(void)
 {
-	unsigned int size, check_size;
+	unsigned int size;
 	char *path;
 	struct stat st;
 	int ret;
@@ -461,11 +402,8 @@ static void read_ftrace_printk(void)
 		write_or_die(&size, 4);
 		goto out;
 	}
-	size = get_size(path);
-	write_or_die(&size, 4);
-	check_size = copy_file(path);
-	if (size != check_size)
-		die("error in size of file '%s'", path);
+	record_file(path, 4);
+
 out:
 	put_tracing_file(path);
 }
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index fc784284ac8..0128906bac8 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -238,6 +238,7 @@ char **argv_split(const char *str, int *argcp);
 void argv_free(char **argv);
 bool strglobmatch(const char *str, const char *pat);
 bool strlazymatch(const char *str, const char *pat);
+int strtailcmp(const char *s1, const char *s2);
 unsigned long convert_unit(unsigned long value, char *unit);
 int readn(int fd, void *buf, size_t size);