Merge branch 'perf-probes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-probes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Issue at least one memory barrier in stop_machine_text_poke()
  perf probe: Correct probe syntax on command line help
  perf probe: Add lazy line matching support
  perf probe: Show more lines after last line
  perf probe: Check function address range strictly in line finder
  perf probe: Use libdw callback routines
  perf probe: Use elfutils-libdw for analyzing debuginfo
  perf probe: Rename probe finder functions
  perf probe: Fix bugs in line range finder
  perf probe: Update perf probe document
  perf probe: Do not show --line option without dwarf support
  kprobes: Add documents of jump optimization
  kprobes/x86: Support kprobes jump optimization on x86
  x86: Add text_poke_smp for SMP cross modifying code
  kprobes/x86: Cleanup save/restore registers
  kprobes/x86: Boost probes when reentering
  kprobes: Jump optimization sysctl interface
  kprobes: Introduce kprobes jump optimization
  kprobes: Introduce generic insn_slot framework
  kprobes/x86: Cleanup RELATIVEJUMP_INSTRUCTION to RELATIVEJUMP_OPCODE

8 files changed, 644 insertions, 626 deletions

diff --git a/tools/perf/Documentation/perf-probe.txt b/tools/perf/Documentation/perf-probe.txt
index 2de34075f6a..34202b1be0b 100644
--- a/tools/perf/Documentation/perf-probe.txt
+++ b/tools/perf/Documentation/perf-probe.txt
@@ -41,7 +41,8 @@ OPTIONS
 
 -d::
 --del=::
-	Delete a probe event.
+	Delete probe events. This accepts glob wildcards('*', '?') and character
+	classes(e.g. [a-z], [!A-Z]).
 
 -l::
 --list::
@@ -50,17 +51,29 @@ OPTIONS
 -L::
 --line=::
 	Show source code lines which can be probed. This needs an argument
-	which specifies a range of the source code.
+	which specifies a range of the source code. (see LINE SYNTAX for detail)
+
+-f::
+--force::
+	Forcibly add events with existing name.
 
 PROBE SYNTAX
 ------------
 Probe points are defined by following syntax.
 
- "[EVENT=]FUNC[+OFFS|:RLN|%return][@SRC]|SRC:ALN [ARG ...]"
+    1) Define event based on function name
+     [EVENT=]FUNC[@SRC][:RLN|+OFFS|%return|;PTN] [ARG ...]
+
+    2) Define event based on source file with line number
+     [EVENT=]SRC:ALN [ARG ...]
+
+    3) Define event based on source file with lazy pattern
+     [EVENT=]SRC;PTN [ARG ...]
+
 
 'EVENT' specifies the name of new event, if omitted, it will be set the name of the probed function. Currently, event group name is set as 'probe'.
-'FUNC' specifies a probed function name, and it may have one of the following options; '+OFFS' is the offset from function entry address in bytes, 'RLN' is the relative-line number from function entry line, and '%return' means that it probes function return. In addition, 'SRC' specifies a source file which has that function.
-It is also possible to specify a probe point by the source line number by using 'SRC:ALN' syntax, where 'SRC' is the source file path and 'ALN' is the line number.
+'FUNC' specifies a probed function name, and it may have one of the following options; '+OFFS' is the offset from function entry address in bytes, ':RLN' is the relative-line number from function entry line, and '%return' means that it probes function return. And ';PTN' means lazy matching pattern (see LAZY MATCHING). Note that ';PTN' must be the end of the probe point definition.  In addition, '@SRC' specifies a source file which has that function.
+It is also possible to specify a probe point by the source line number or lazy matching by using 'SRC:ALN' or 'SRC;PTN' syntax, where 'SRC' is the source file path, ':ALN' is the line number and ';PTN' is the lazy matching pattern.
 'ARG' specifies the arguments of this probe point. You can use the name of local variable, or kprobe-tracer argument format (e.g. $retval, %ax, etc).
 
 LINE SYNTAX
@@ -76,6 +89,41 @@ and 'ALN2' is end line number in the file. It is also possible to specify how
 many lines to show by using 'NUM'.
 So, "source.c:100-120" shows lines between 100th to l20th in source.c file. And "func:10+20" shows 20 lines from 10th line of func function.
 
+LAZY MATCHING
+-------------
+ The lazy line matching is similar to glob matching but ignoring spaces in both of pattern and target. So this accepts wildcards('*', '?') and character classes(e.g. [a-z], [!A-Z]).
+
+e.g.
+ 'a=*' can matches 'a=b', 'a = b', 'a == b' and so on.
+
+This provides some sort of flexibility and robustness to probe point definitions against minor code changes. For example, actual 10th line of schedule() can be moved easily by modifying schedule(), but the same line matching 'rq=cpu_rq*' may still exist in the function.)
+
+
+EXAMPLES
+--------
+Display which lines in schedule() can be probed:
+
+ ./perf probe --line schedule
+
+Add a probe on schedule() function 12th line with recording cpu local variable:
+
+ ./perf probe schedule:12 cpu
+ or
+ ./perf probe --add='schedule:12 cpu'
+
+ this will add one or more probes which has the name start with "schedule".
+
+ Add probes on lines in schedule() function which calls update_rq_clock().
+
+ ./perf probe 'schedule;update_rq_clock*'
+ or
+ ./perf probe --add='schedule;update_rq_clock*'
+
+Delete all probes on schedule().
+
+ ./perf probe --del='schedule*'
+
+
 SEE ALSO
 --------
 linkperf:perf-trace[1], linkperf:perf-record[1]
diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 54a5b50ff31..2d537382c68 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -500,12 +500,12 @@ else
 	msg := $(error No libelf.h/libelf found, please install libelf-dev/elfutils-libelf-devel and glibc-dev[el]);
 endif
 
-ifneq ($(shell sh -c "(echo '\#ifndef _MIPS_SZLONG'; echo '\#define _MIPS_SZLONG 0'; echo '\#endif'; echo '\#include <dwarf.h>'; echo '\#include <libdwarf.h>'; echo 'int main(void) { Dwarf_Debug dbg; Dwarf_Error err; Dwarf_Ranges *rng; dwarf_init(0, DW_DLC_READ, 0, 0, &dbg, &err); dwarf_get_ranges(dbg, 0, &rng, 0, 0, &err); return (long)dbg; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -I/usr/include/libdwarf -ldwarf -lelf -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y)
-	msg := $(warning No libdwarf.h found or old libdwarf.h found, disables dwarf support. Please install libdwarf-dev/libdwarf-devel >= 20081231);
-	BASIC_CFLAGS += -DNO_LIBDWARF
+ifneq ($(shell sh -c "(echo '\#include <dwarf.h>'; echo '\#include <libdw.h>'; echo 'int main(void) { Dwarf *dbg; dbg = dwarf_begin(0, DWARF_C_READ); return (long)dbg; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -I/usr/include/elfutils -ldw -lelf -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y)
+	msg := $(warning No libdw.h found or old libdw.h found, disables dwarf support. Please install elfutils-devel/elfutils-dev);
+	BASIC_CFLAGS += -DNO_DWARF_SUPPORT
 else
-	BASIC_CFLAGS += -I/usr/include/libdwarf
-	EXTLIBS += -lelf -ldwarf
+	BASIC_CFLAGS += -I/usr/include/elfutils
+	EXTLIBS += -lelf -ldw
 	LIB_OBJS += util/probe-finder.o
 endif
 
diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index ad47bd4c50e..c30a3359234 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -128,7 +128,7 @@ static void evaluate_probe_point(struct probe_point *pp)
 		    pp->function);
 }
 
-#ifndef NO_LIBDWARF
+#ifndef NO_DWARF_SUPPORT
 static int open_vmlinux(void)
 {
 	if (map__load(session.kmaps[MAP__FUNCTION], NULL) < 0) {
@@ -156,14 +156,16 @@ static const char * const probe_usage[] = {
 	"perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
 	"perf probe [<options>] --del '[GROUP:]EVENT' ...",
 	"perf probe --list",
+#ifndef NO_DWARF_SUPPORT
 	"perf probe --line 'LINEDESC'",
+#endif
 	NULL
 };
 
 static const struct option options[] = {
 	OPT_BOOLEAN('v', "verbose", &verbose,
 		    "be more verbose (show parsed arguments, etc)"),
-#ifndef NO_LIBDWARF
+#ifndef NO_DWARF_SUPPORT
 	OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
 		   "file", "vmlinux pathname"),
 #endif
@@ -172,30 +174,32 @@ static const struct option options[] = {
 	OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
 		opt_del_probe_event),
 	OPT_CALLBACK('a', "add", NULL,
-#ifdef NO_LIBDWARF
-		"[EVENT=]FUNC[+OFFS|%return] [ARG ...]",
+#ifdef NO_DWARF_SUPPORT
+		"[EVENT=]FUNC[+OFF|%return] [ARG ...]",
 #else
-		"[EVENT=]FUNC[+OFFS|%return|:RLN][@SRC]|SRC:ALN [ARG ...]",
+		"[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT"
+		" [ARG ...]",
 #endif
 		"probe point definition, where\n"
 		"\t\tGROUP:\tGroup name (optional)\n"
 		"\t\tEVENT:\tEvent name\n"
 		"\t\tFUNC:\tFunction name\n"
-		"\t\tOFFS:\tOffset from function entry (in byte)\n"
+		"\t\tOFF:\tOffset from function entry (in byte)\n"
 		"\t\t%return:\tPut the probe at function return\n"
-#ifdef NO_LIBDWARF
+#ifdef NO_DWARF_SUPPORT
 		"\t\tARG:\tProbe argument (only \n"
 #else
 		"\t\tSRC:\tSource code path\n"
-		"\t\tRLN:\tRelative line number from function entry.\n"
-		"\t\tALN:\tAbsolute line number in file.\n"
+		"\t\tRL:\tRelative line number from function entry.\n"
+		"\t\tAL:\tAbsolute line number in file.\n"
+		"\t\tPT:\tLazy expression of line code.\n"
 		"\t\tARG:\tProbe argument (local variable name or\n"
 #endif
 		"\t\t\tkprobe-tracer argument format.)\n",
 		opt_add_probe_event),
 	OPT_BOOLEAN('f', "force", &session.force_add, "forcibly add events"
 		    " with existing name"),
-#ifndef NO_LIBDWARF
+#ifndef NO_DWARF_SUPPORT
 	OPT_CALLBACK('L', "line", NULL,
 		     "FUNC[:RLN[+NUM|:RLN2]]|SRC:ALN[+NUM|:ALN2]",
 		     "Show source code lines.", opt_show_lines),
@@ -223,7 +227,7 @@ static void init_vmlinux(void)
 int cmd_probe(int argc, const char **argv, const char *prefix __used)
 {
 	int i, ret;
-#ifndef NO_LIBDWARF
+#ifndef NO_DWARF_SUPPORT
 	int fd;
 #endif
 	struct probe_point *pp;
@@ -259,7 +263,7 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
 		return 0;
 	}
 
-#ifndef NO_LIBDWARF
+#ifndef NO_DWARF_SUPPORT
 	if (session.show_lines) {
 		if (session.nr_probe != 0 || session.dellist) {
 			pr_warning("  Error: Don't use --line with"
@@ -290,9 +294,9 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
 	init_vmlinux();
 
 	if (session.need_dwarf)
-#ifdef NO_LIBDWARF
+#ifdef NO_DWARF_SUPPORT
 		die("Debuginfo-analysis is not supported");
-#else	/* !NO_LIBDWARF */
+#else	/* !NO_DWARF_SUPPORT */
 		pr_debug("Some probes require debuginfo.\n");
 
 	fd = open_vmlinux();
@@ -312,7 +316,7 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
 			continue;
 
 		lseek(fd, SEEK_SET, 0);
-		ret = find_probepoint(fd, pp);
+		ret = find_probe_point(fd, pp);
 		if (ret > 0)
 			continue;
 		if (ret == 0) {	/* No error but failed to find probe point. */
@@ -333,7 +337,7 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
 	close(fd);
 
 end_dwarf:
-#endif /* !NO_LIBDWARF */
+#endif /* !NO_DWARF_SUPPORT */
 
 	/* Synthesize probes without dwarf */
 	for (i = 0; i < session.nr_probe; i++) {
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 8f056884969..c971e81e9cb 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -119,14 +119,14 @@ static void parse_perf_probe_probepoint(char *arg, struct probe_point *pp)
 	char c, nc = 0;
 	/*
 	 * <Syntax>
-	 * perf probe [EVENT=]SRC:LN
-	 * perf probe [EVENT=]FUNC[+OFFS|%return][@SRC]
+	 * perf probe [EVENT=]SRC[:LN|;PTN]
+	 * perf probe [EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT]
 	 *
 	 * TODO:Group name support
 	 */
 
-	ptr = strchr(arg, '=');
-	if (ptr) {	/* Event name */
+	ptr = strpbrk(arg, ";=@+%");
+	if (ptr && *ptr == '=') {	/* Event name */
 		*ptr = '\0';
 		tmp = ptr + 1;
 		ptr = strchr(arg, ':');
@@ -139,7 +139,7 @@ static void parse_perf_probe_probepoint(char *arg, struct probe_point *pp)
 		arg = tmp;
 	}
 
-	ptr = strpbrk(arg, ":+@%");
+	ptr = strpbrk(arg, ";:+@%");
 	if (ptr) {
 		nc = *ptr;
 		*ptr++ = '\0';
@@ -156,7 +156,11 @@ static void parse_perf_probe_probepoint(char *arg, struct probe_point *pp)
 	while (ptr) {
 		arg = ptr;
 		c = nc;
-		ptr = strpbrk(arg, ":+@%");
+		if (c == ';') {	/* Lazy pattern must be the last part */
+			pp->lazy_line = strdup(arg);
+			break;
+		}
+		ptr = strpbrk(arg, ";:+@%");
 		if (ptr) {
 			nc = *ptr;
 			*ptr++ = '\0';
@@ -165,13 +169,13 @@ static void parse_perf_probe_probepoint(char *arg, struct probe_point *pp)
 		case ':':	/* Line number */
 			pp->line = strtoul(arg, &tmp, 0);
 			if (*tmp != '\0')
-				semantic_error("There is non-digit charactor"
-						" in line number.");
+				semantic_error("There is non-digit char"
+					       " in line number.");
 			break;
 		case '+':	/* Byte offset from a symbol */
 			pp->offset = strtoul(arg, &tmp, 0);
 			if (*tmp != '\0')
-				semantic_error("There is non-digit charactor"
+				semantic_error("There is non-digit character"
 						" in offset.");
 			break;
 		case '@':	/* File name */
@@ -179,9 +183,6 @@ static void parse_perf_probe_probepoint(char *arg, struct probe_point *pp)
 				semantic_error("SRC@SRC is not allowed.");
 			pp->file = strdup(arg);
 			DIE_IF(pp->file == NULL);
-			if (ptr)
-				semantic_error("@SRC must be the last "
-					       "option.");
 			break;
 		case '%':	/* Probe places */
 			if (strcmp(arg, "return") == 0) {
@@ -196,11 +197,18 @@ static void parse_perf_probe_probepoint(char *arg, struct probe_point *pp)
 	}
 
 	/* Exclusion check */
+	if (pp->lazy_line && pp->line)
+		semantic_error("Lazy pattern can't be used with line number.");
+
+	if (pp->lazy_line && pp->offset)
+		semantic_error("Lazy pattern can't be used with offset.");
+
 	if (pp->line && pp->offset)
 		semantic_error("Offset can't be used with line number.");
 
-	if (!pp->line && pp->file && !pp->function)
-		semantic_error("File always requires line number.");
+	if (!pp->line && !pp->lazy_line && pp->file && !pp->function)
+		semantic_error("File always requires line number or "
+			       "lazy pattern.");
 
 	if (pp->offset && !pp->function)
 		semantic_error("Offset requires an entry function.");
@@ -208,11 +216,13 @@ static void parse_perf_probe_probepoint(char *arg, struct probe_point *pp)
 	if (pp->retprobe && !pp->function)
 		semantic_error("Return probe requires an entry function.");
 
-	if ((pp->offset || pp->line) && pp->retprobe)
-		semantic_error("Offset/Line can't be used with return probe.");
+	if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe)
+		semantic_error("Offset/Line/Lazy pattern can't be used with "
+			       "return probe.");
 
-	pr_debug("symbol:%s file:%s line:%d offset:%d, return:%d\n",
-		 pp->function, pp->file, pp->line, pp->offset, pp->retprobe);
+	pr_debug("symbol:%s file:%s line:%d offset:%d return:%d lazy:%s\n",
+		 pp->function, pp->file, pp->line, pp->offset, pp->retprobe,
+		 pp->lazy_line);
 }
 
 /* Parse perf-probe event definition */
@@ -458,6 +468,8 @@ static void clear_probe_point(struct probe_point *pp)
 		free(pp->function);
 	if (pp->file)
 		free(pp->file);
+	if (pp->lazy_line)
+		free(pp->lazy_line);
 	for (i = 0; i < pp->nr_args; i++)
 		free(pp->args[i]);
 	if (pp->args)
@@ -719,6 +731,7 @@ void del_trace_kprobe_events(struct strlist *dellist)
 }
 
 #define LINEBUF_SIZE 256
+#define NR_ADDITIONAL_LINES 2
 
 static void show_one_line(FILE *fp, unsigned int l, bool skip, bool show_num)
 {
@@ -779,5 +792,11 @@ void show_line_range(struct line_range *lr)
 			show_one_line(fp, (l++) - lr->offset, false, false);
 		show_one_line(fp, (l++) - lr->offset, false, true);
 	}
+
+	if (lr->end == INT_MAX)
+		lr->end = l + NR_ADDITIONAL_LINES;
+	while (l < lr->end && !feof(fp))
+		show_one_line(fp, (l++) - lr->offset, false, false);
+
 	fclose(fp);
 }
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 1b2124d12f6..e77dc886760 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -32,21 +32,13 @@
 #include <stdarg.h>
 #include <ctype.h>
 
+#include "string.h"
 #include "event.h"
 #include "debug.h"
 #include "util.h"
 #include "probe-finder.h"
 
 
-/* Dwarf_Die Linkage to parent Die */
-struct die_link {
-	struct die_link *parent;	/* Parent die */
-	Dwarf_Die die;			/* Current die */
-};
-
-static Dwarf_Debug __dw_debug;
-static Dwarf_Error __dw_error;
-
 /*
  * Generic dwarf analysis helpers
  */
@@ -113,281 +105,190 @@ static int strtailcmp(const char *s1, const char *s2)
 	return 0;
 }
 
-/* Find the fileno of the target file. */
-static Dwarf_Unsigned cu_find_fileno(Dwarf_Die cu_die, const char *fname)
-{
-	Dwarf_Signed cnt, i;
-	Dwarf_Unsigned found = 0;
-	char **srcs;
-	int ret;
+/* Line number list operations */
 
-	if (!fname)
-		return 0;
+/* Add a line to line number list */
+static void line_list__add_line(struct list_head *head, unsigned int line)
+{
+	struct line_node *ln;
+	struct list_head *p;
 
-	ret = dwarf_srcfiles(cu_die, &srcs, &cnt, &__dw_error);
-	if (ret == DW_DLV_OK) {
-		for (i = 0; i < cnt && !found; i++) {
-			if (strtailcmp(srcs[i], fname) == 0)
-				found = i + 1;
-			dwarf_dealloc(__dw_debug, srcs[i], DW_DLA_STRING);
-		}
-		for (; i < cnt; i++)
-			dwarf_dealloc(__dw_debug, srcs[i], DW_DLA_STRING);
-		dwarf_dealloc(__dw_debug, srcs, DW_DLA_LIST);
+	/* Reverse search, because new line will be the last one */
+	list_for_each_entry_reverse(ln, head, list) {
+		if (ln->line < line) {
+			p = &ln->list;
+			goto found;
+		} else if (ln->line == line)	/* Already exist */
+			return ;
 	}
-	if (found)
-		pr_debug("found fno: %d\n", (int)found);
-	return found;
+	/* List is empty, or the smallest entry */
+	p = head;
+found:
+	pr_debug("line list: add a line %u\n", line);
+	ln = zalloc(sizeof(struct line_node));
+	DIE_IF(ln == NULL);
+	ln->line = line;
+	INIT_LIST_HEAD(&ln->list);
+	list_add(&ln->list, p);
 }
 
-static int cu_get_filename(Dwarf_Die cu_die, Dwarf_Unsigned fno, char **buf)
+/* Check if the line in line number list */
+static int line_list__has_line(struct list_head *head, unsigned int line)
 {
-	Dwarf_Signed cnt, i;
-	char **srcs;
-	int ret = 0;
-
-	if (!buf || !fno)
-		return -EINVAL;
-
-	ret = dwarf_srcfiles(cu_die, &srcs, &cnt, &__dw_error);
-	if (ret == DW_DLV_OK) {
-		if ((Dwarf_Unsigned)cnt > fno - 1) {
-			*buf = strdup(srcs[fno - 1]);
-			ret = 0;
-			pr_debug("found filename: %s\n", *buf);
-		} else
-			ret = -ENOENT;
-		for (i = 0; i < cnt; i++)
-			dwarf_dealloc(__dw_debug, srcs[i], DW_DLA_STRING);
-		dwarf_dealloc(__dw_debug, srcs, DW_DLA_LIST);
-	} else
-		ret = -EINVAL;
-	return ret;
+	struct line_node *ln;
+
+	/* Reverse search, because new line will be the last one */
+	list_for_each_entry(ln, head, list)
+		if (ln->line == line)
+			return 1;
+
+	return 0;
 }
 
-/* Compare diename and tname */
-static int die_compare_name(Dwarf_Die dw_die, const char *tname)
+/* Init line number list */
+static void line_list__init(struct list_head *head)
 {
-	char *name;
-	int ret;
-	ret = dwarf_diename(dw_die, &name, &__dw_error);
-	DIE_IF(ret == DW_DLV_ERROR);
-	if (ret == DW_DLV_OK) {
-		ret = strcmp(tname, name);
-		dwarf_dealloc(__dw_debug, name, DW_DLA_STRING);
-	} else
-		ret = -1;
-	return ret;
+	INIT_LIST_HEAD(head);
 }
 
-/* Check the address is in the subprogram(function). */
-static int die_within_subprogram(Dwarf_Die sp_die, Dwarf_Addr addr,
-				 Dwarf_Signed *offs)
+/* Free line number list */
+static void line_list__free(struct list_head *head)
 {
-	Dwarf_Addr lopc, hipc;
-	int ret;
-
-	/* TODO: check ranges */
-	ret = dwarf_lowpc(sp_die, &lopc, &__dw_error);
-	DIE_IF(ret == DW_DLV_ERROR);
-	if (ret == DW_DLV_NO_ENTRY)
-		return 0;
-	ret = dwarf_highpc(sp_die, &hipc, &__dw_error);
-	DIE_IF(ret != DW_DLV_OK);
-	if (lopc <= addr && addr < hipc) {
-		*offs = addr - lopc;
-		return 1;
-	} else
-		return 0;
+	struct line_node *ln;
+	while (!list_empty(head)) {
+		ln = list_first_entry(head, struct line_node, list);
+		list_del(&ln->list);
+		free(ln);
+	}
 }
 
-/* Check the die is inlined function */
-static Dwarf_Bool die_inlined_subprogram(Dwarf_Die dw_die)
+/* Dwarf wrappers */
+
+/* Find the realpath of the target file. */
+static const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname)
 {
-	/* TODO: check strictly */
-	Dwarf_Bool inl;
+	Dwarf_Files *files;
+	size_t nfiles, i;
+	const char *src;
 	int ret;
 
-	ret = dwarf_hasattr(dw_die, DW_AT_inline, &inl, &__dw_error);
-	DIE_IF(ret == DW_DLV_ERROR);
-	return inl;
-}
+	if (!fname)
+		return NULL;
 
-/* Get the offset of abstruct_origin */
-static Dwarf_Off die_get_abstract_origin(Dwarf_Die dw_die)
-{
-	Dwarf_Attribute attr;
-	Dwarf_Off cu_offs;
-	int ret;
+	ret = dwarf_getsrcfiles(cu_die, &files, &nfiles);
+	if (ret != 0)
+		return NULL;
 
-	ret = dwarf_attr(dw_die, DW_AT_abstract_origin, &attr, &__dw_error);
-	DIE_IF(ret != DW_DLV_OK);
-	ret = dwarf_formref(attr, &cu_offs, &__dw_error);
-	DIE_IF(ret != DW_DLV_OK);
-	dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR);
-	return cu_offs;
+	for (i = 0; i < nfiles; i++) {
+		src = dwarf_filesrc(files, i, NULL, NULL);
+		if (strtailcmp(src, fname) == 0)
+			break;
+	}
+	return src;
 }
 
-/* Get entry pc(or low pc, 1st entry of ranges)  of the die */
-static Dwarf_Addr die_get_entrypc(Dwarf_Die dw_die)
+struct __addr_die_search_param {
+	Dwarf_Addr	addr;
+	Dwarf_Die	*die_mem;
+};
+
+static int __die_search_func_cb(Dwarf_Die *fn_die, void *data)
 {
-	Dwarf_Attribute attr;
-	Dwarf_Addr addr;
-	Dwarf_Off offs;
-	Dwarf_Ranges *ranges;
-	Dwarf_Signed cnt;
-	int ret;
+	struct __addr_die_search_param *ad = data;
 
-	/* Try to get entry pc */
-	ret = dwarf_attr(dw_die, DW_AT_entry_pc, &attr, &__dw_error);
-	DIE_IF(ret == DW_DLV_ERROR);
-	if (ret == DW_DLV_OK) {
-		ret = dwarf_formaddr(attr, &addr, &__dw_error);
-		DIE_IF(ret != DW_DLV_OK);
-		dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR);
-		return addr;
+	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;
+}
 
-	/* Try to get low pc */
-	ret = dwarf_lowpc(dw_die, &addr, &__dw_error);
-	DIE_IF(ret == DW_DLV_ERROR);
-	if (ret == DW_DLV_OK)
-		return addr;
-
-	/* Try to get ranges */
-	ret = dwarf_attr(dw_die, DW_AT_ranges, &attr, &__dw_error);
-	DIE_IF(ret != DW_DLV_OK);
-	ret = dwarf_formref(attr, &offs, &__dw_error);
-	DIE_IF(ret != DW_DLV_OK);
-	ret = dwarf_get_ranges(__dw_debug, offs, &ranges, &cnt, NULL,
-				&__dw_error);
-	DIE_IF(ret != DW_DLV_OK);
-	addr = ranges[0].dwr_addr1;
-	dwarf_ranges_dealloc(__dw_debug, ranges, cnt);
-	return addr;
+/* Search a real subprogram including this line, */
+static Dwarf_Die *die_get_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;
 }
 
-/*
- * Search a Die from Die tree.
- * Note: cur_link->die should be deallocated in this function.
- */
-static int __search_die_tree(struct die_link *cur_link,
-			     int (*die_cb)(struct die_link *, void *),
-			     void *data)
+/* Similar to dwarf_getfuncs, but returns inlined_subroutine if exists. */
+static Dwarf_Die *die_get_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
+				     Dwarf_Die *die_mem)
 {
-	Dwarf_Die new_die;
-	struct die_link new_link;
+	Dwarf_Die child_die;
 	int ret;
 
-	if (!die_cb)
-		return 0;
-
-	/* Check current die */
-	while (!(ret = die_cb(cur_link, data))) {
-		/* Check child die */
-		ret = dwarf_child(cur_link->die, &new_die, &__dw_error);
-		DIE_IF(ret == DW_DLV_ERROR);
-		if (ret == DW_DLV_OK) {
-			new_link.parent = cur_link;
-			new_link.die = new_die;
-			ret = __search_die_tree(&new_link, die_cb, data);
-			if (ret)
-				break;
-		}
+	ret = dwarf_child(sp_die, die_mem);
+	if (ret != 0)
+		return NULL;
 
-		/* Move to next sibling */
-		ret = dwarf_siblingof(__dw_debug, cur_link->die, &new_die,
-				      &__dw_error);
-		DIE_IF(ret == DW_DLV_ERROR);
-		dwarf_dealloc(__dw_debug, cur_link->die, DW_DLA_DIE);
-		cur_link->die = new_die;
-		if (ret == DW_DLV_NO_ENTRY)
-			return 0;
-	}
-	dwarf_dealloc(__dw_debug, cur_link->die, DW_DLA_DIE);
-	return ret;
-}
+	do {
+		if (dwarf_tag(die_mem) == DW_TAG_inlined_subroutine &&
+		    dwarf_haspc(die_mem, addr))
+			return die_mem;
 
-/* Search a die in its children's die tree */
-static int search_die_from_children(Dwarf_Die parent_die,
-				    int (*die_cb)(struct die_link *, void *),
-				    void *data)
-{
-	struct die_link new_link;
-	int ret;
+		if (die_get_inlinefunc(die_mem, addr, &child_die)) {
+			memcpy(die_mem, &child_die, sizeof(Dwarf_Die));
+			return die_mem;
+		}
+	} while (dwarf_siblingof(die_mem, die_mem) == 0);
 
-	new_link.parent = NULL;
-	ret = dwarf_child(parent_die, &new_link.die, &__dw_error);
-	DIE_IF(ret == DW_DLV_ERROR);
-	if (ret == DW_DLV_OK)
-		return __search_die_tree(&new_link, die_cb, data);
-	else
-		return 0;
+	return NULL;
 }
 
-/* Find a locdesc corresponding to the address */
-static int attr_get_locdesc(Dwarf_Attribute attr, Dwarf_Locdesc *desc,
-			    Dwarf_Addr addr)
+/* Compare diename and tname */
+static bool die_compare_name(Dwarf_Die *dw_die, const char *tname)
 {
-	Dwarf_Signed lcnt;
-	Dwarf_Locdesc **llbuf;
-	int ret, i;
-
-	ret = dwarf_loclist_n(attr, &llbuf, &lcnt, &__dw_error);
-	DIE_IF(ret != DW_DLV_OK);
-	ret = DW_DLV_NO_ENTRY;
-	for (i = 0; i < lcnt; ++i) {
-		if (llbuf[i]->ld_lopc <= addr &&
-		    llbuf[i]->ld_hipc > addr) {
-			memcpy(desc, llbuf[i], sizeof(Dwarf_Locdesc));
-			desc->ld_s =
-				malloc(sizeof(Dwarf_Loc) * llbuf[i]->ld_cents);
-			DIE_IF(desc->ld_s == NULL);
-			memcpy(desc->ld_s, llbuf[i]->ld_s,
-				sizeof(Dwarf_Loc) * llbuf[i]->ld_cents);
-			ret = DW_DLV_OK;
-			break;
-		}
-		dwarf_dealloc(__dw_debug, llbuf[i]->ld_s, DW_DLA_LOC_BLOCK);
-		dwarf_dealloc(__dw_debug, llbuf[i], DW_DLA_LOCDESC);
-	}
-	/* Releasing loop */
-	for (; i < lcnt; ++i) {
-		dwarf_dealloc(__dw_debug, llbuf[i]->ld_s, DW_DLA_LOC_BLOCK);
-		dwarf_dealloc(__dw_debug, llbuf[i], DW_DLA_LOCDESC);
-	}
-	dwarf_dealloc(__dw_debug, llbuf, DW_DLA_LIST);
-	return ret;
+	const char *name;
+	name = dwarf_diename(dw_die);
+	DIE_IF(name == NULL);
+	return strcmp(tname, name);
 }
 
-/* Get decl_file attribute value (file number) */
-static Dwarf_Unsigned die_get_decl_file(Dwarf_Die sp_die)
+/* Get entry pc(or low pc, 1st entry of ranges)  of the die */
+static Dwarf_Addr die_get_entrypc(Dwarf_Die *dw_die)
 {
-	Dwarf_Attribute attr;
-	Dwarf_Unsigned fno;
+	Dwarf_Addr epc;
 	int ret;
 
-	ret = dwarf_attr(sp_die, DW_AT_decl_file, &attr, &__dw_error);
-	DIE_IF(ret != DW_DLV_OK);
-	dwarf_formudata(attr, &fno, &__dw_error);
-	DIE_IF(ret != DW_DLV_OK);
-	dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR);
-	return fno;
+	ret = dwarf_entrypc(dw_die, &epc);
+	DIE_IF(ret == -1);
+	return epc;
 }
 
-/* Get decl_line attribute value (line number) */
-static Dwarf_Unsigned die_get_decl_line(Dwarf_Die sp_die)
+/* Get a variable die */
+static Dwarf_Die *die_find_variable(Dwarf_Die *sp_die, const char *name,
+				    Dwarf_Die *die_mem)
 {
-	Dwarf_Attribute attr;
-	Dwarf_Unsigned lno;
+	Dwarf_Die child_die;
+	int tag;
 	int ret;
 
-	ret = dwarf_attr(sp_die, DW_AT_decl_line, &attr, &__dw_error);
-	DIE_IF(ret != DW_DLV_OK);
-	dwarf_formudata(attr, &lno, &__dw_error);
-	DIE_IF(ret != DW_DLV_OK);
-	dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR);
-	return lno;
+	ret = dwarf_child(sp_die, die_mem);
+	if (ret != 0)
+		return NULL;
+
+	do {
+		tag = dwarf_tag(die_mem);
+		if ((tag == DW_TAG_formal_parameter ||
+		     tag == DW_TAG_variable) &&
+		    (die_compare_name(die_mem, name) == 0))
+			return die_mem;
+
+		if (die_find_variable(die_mem, name, &child_die)) {
+			memcpy(die_mem, &child_die, sizeof(Dwarf_Die));
+			return die_mem;
+		}
+	} while (dwarf_siblingof(die_mem, die_mem) == 0);
+
+	return NULL;
 }
 
 /*
@@ -395,47 +296,45 @@ static Dwarf_Unsigned die_get_decl_line(Dwarf_Die sp_die)
  */
 
 /* Show a location */
-static void show_location(Dwarf_Loc *loc, struct probe_finder *pf)
+static void show_location(Dwarf_Op *op, struct probe_finder *pf)
 {
-	Dwarf_Small op;
-	Dwarf_Unsigned regn;
-	Dwarf_Signed offs;
+	unsigned int regn;
+	Dwarf_Word offs = 0;
 	int deref = 0, ret;
 	const char *regs;
 
-	op = loc->lr_atom;
-
+	/* TODO: support CFA */
 	/* If this is based on frame buffer, set the offset */
-	if (op == DW_OP_fbreg) {
+	if (op->atom == DW_OP_fbreg) {
+		if (pf->fb_ops == NULL)
+			die("The attribute of frame base is not supported.\n");
 		deref = 1;
-		offs = (Dwarf_Signed)loc->lr_number;
-		op = pf->fbloc.ld_s[0].lr_atom;
-		loc = &pf->fbloc.ld_s[0];
-	} else
-		offs = 0;
+		offs = op->number;
+		op = &pf->fb_ops[0];
+	}
 
-	if (op >= DW_OP_breg0 && op <= DW_OP_breg31) {
-		regn = op - DW_OP_breg0;
-		offs += (Dwarf_Signed)loc->lr_number;
+	if (op->atom >= DW_OP_breg0 && op->atom <= DW_OP_breg31) {
+		regn = op->atom - DW_OP_breg0;
+		offs += op->number;
 		deref = 1;
-	} else if (op >= DW_OP_reg0 && op <= DW_OP_reg31) {
-		regn = op - DW_OP_reg0;
-	} else if (op == DW_OP_bregx) {
-		regn = loc->lr_number;
-		offs += (Dwarf_Signed)loc->lr_number2;
+	} else if (op->atom >= DW_OP_reg0 && op->atom <= DW_OP_reg31) {
+		regn = op->atom - DW_OP_reg0;
+	} else if (op->atom == DW_OP_bregx) {
+		regn = op->number;
+		offs += op->number2;
 		deref = 1;
-	} else if (op == DW_OP_regx) {
-		regn = loc->lr_number;
+	} else if (op->atom == DW_OP_regx) {
+		regn = op->number;
 	} else
-		die("Dwarf_OP %d is not supported.", op);
+		die("DW_OP %d is not supported.", op->atom);
 
 	regs = get_arch_regstr(regn);
 	if (!regs)
-		die("%lld exceeds max register number.", regn);
+		die("%u exceeds max register number.", regn);
 
 	if (deref)
-		ret = snprintf(pf->buf, pf->len,
-				 " %s=%+lld(%s)", pf->var, offs, regs);
+		ret = snprintf(pf->buf, pf->len, " %s=+%ju(%s)",
+			       pf->var, (uintmax_t)offs, regs);
 	else
 		ret = snprintf(pf->buf, pf->len, " %s=%s", pf->var, regs);
 	DIE_IF(ret < 0);
@@ -443,52 +342,37 @@ static void show_location(Dwarf_Loc *loc, struct probe_finder *pf)
 }
 
 /* Show a variables in kprobe event format */
-static void show_variable(Dwarf_Die vr_die, struct probe_finder *pf)
+static void show_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
 {
 	Dwarf_Attribute attr;
-	Dwarf_Locdesc ld;
+	Dwarf_Op *expr;
+	size_t nexpr;
 	int ret;
 
-	ret = dwarf_attr(vr_die, DW_AT_location, &attr, &__dw_error);
-	if (ret != DW_DLV_OK)
+	if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL)
 		goto error;
-	ret = attr_get_locdesc(attr, &ld, (pf->addr - pf->cu_base));
-	if (ret != DW_DLV_OK)
+	/* TODO: handle more than 1 exprs */
+	ret = dwarf_getlocation_addr(&attr, (pf->addr - pf->cu_base),
+				     &expr, &nexpr, 1);
+	if (ret <= 0 || nexpr == 0)
 		goto error;
-	/* TODO? */
-	DIE_IF(ld.ld_cents != 1);
-	show_location(&ld.ld_s[0], pf);
-	free(ld.ld_s);
-	dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR);
+
+	show_location(expr, pf);
+	/* *expr will be cached in libdw. Don't free it. */
 	return ;
 error:
+	/* TODO: Support const_value */
 	die("Failed to find the location of %s at this address.\n"
 	    " Perhaps, it has been optimized out.", pf->var);
 }
 
-static int variable_callback(struct die_link *dlink, void *data)
-{
-	struct probe_finder *pf = (struct probe_finder *)data;
-	Dwarf_Half tag;
-	int ret;
-
-	ret = dwarf_tag(dlink->die, &tag, &__dw_error);
-	DIE_IF(ret == DW_DLV_ERROR);
-	if ((tag == DW_TAG_formal_parameter ||
-	     tag == DW_TAG_variable) &&
-	    (die_compare_name(dlink->die, pf->var) == 0)) {
-		show_variable(dlink->die, pf);
-		return 1;
-	}
-	/* TODO: Support struct members and arrays */
-	return 0;
-}
-
 /* Find a variable in a subprogram die */
-static void find_variable(Dwarf_Die sp_die, struct probe_finder *pf)
+static void find_variable(Dwarf_Die *sp_die, struct probe_finder *pf)
 {
 	int ret;
+	Dwarf_Die vr_die;
 
+	/* TODO: Support struct members and arrays */
 	if (!is_c_varname(pf->var)) {
 		/* Output raw parameters */
 		ret = snprintf(pf->buf, pf->len, " %s", pf->var);
@@ -499,58 +383,51 @@ static void find_variable(Dwarf_Die sp_die, struct probe_finder *pf)
 
 	pr_debug("Searching '%s' variable in context.\n", pf->var);
 	/* Search child die for local variables and parameters. */
-	ret = search_die_from_children(sp_die, variable_callback, pf);
-	if (!ret)
+	if (!die_find_variable(sp_die, pf->var, &vr_die))
 		die("Failed to find '%s' in this function.", pf->var);
-}
-
-/* Get a frame base on the address */
-static void get_current_frame_base(Dwarf_Die sp_die, struct probe_finder *pf)
-{