perf-probe: Move dwarf library routines to dwarf-aux.{c, h}

Move dwarf library related routines to dwarf-aux.{c,h}.
This includes several minor changes.
- Add simple documents for each API.
- Rename die_find_real_subprogram() to die_find_realfunc()
- Rename line_walk_handler_t to line_walk_callback_t.
- Minor cleanups.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Link: http://lkml.kernel.org/r/20110627072727.6528.57647.stgit@fedora15
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

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
 

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;
+}
+

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

tools/perf/util/probe-finder.c

@@ -222,521 +222,6 @@ static Dwarf *dwfl_init_live_kernel_dwarf(Dwarf_Addr addr __used, Dwfl **dwflp,
 }
 #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);
-}
-
-/* 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_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 a child die */
-static 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;
-};
-
-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;
-}
-
-/* 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_END;
-
-	return DIE_FIND_CB_CONTINUE;
-}
-
-/* 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)
-{
-	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;
-}
-
-/* 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_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_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;
-	}
-
-	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;
-}
-
-/* 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_END;
-
-	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;
-}
-
-/* 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)
-{
-	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;
-}
-
 /*
  * Probe finder related functions
  */
@@ -1206,8 +691,7 @@ 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");
@@ -1768,7 +1252,7 @@ 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 ||

tools/perf/util/probe-finder.h

@@ -32,11 +32,7 @@ extern int find_line_range(int fd, struct line_range *lr);
 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>
+#include "dwarf-aux.h"
 
 struct probe_finder {
 	struct perf_probe_event	*pev;		/* Target probe event */