Commit 0dbb1cac authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Arnaldo Carvalho de Melo
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perf probe: Fix finder to find lines of given function 



The commit ba28c59b fixed a declaration
entry bug in probe_point_search_cb().  There are same bugs in line
finder and call_probe_finder().  This introduces a new dwarf utility
function to determine given DIE is a function definition, not
declaration.

Signed-off-by: default avatarMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Prashanth Nageshappa <prashanth@linux.vnet.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20120423032435.8737.80064.stgit@localhost.localdomain


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 33e940a2

tools/perf/util/dwarf-aux.c

+19 −0
Original line number Diff line number Diff line
@@ -262,6 +262,21 @@ bool die_is_signed_type(Dwarf_Die *tp_die) 
		ret == DW_ATE_signed_fixed);

}



/**

 * die_is_func_def - Ensure that this DIE is a subprogram and definition

 * @dw_die: a DIE

 *

 * Ensure that this DIE is a subprogram and NOT a declaration. This

 * returns true if @dw_die is a function definition.

 **/

bool die_is_func_def(Dwarf_Die *dw_die)

{

	Dwarf_Attribute attr;



	return (dwarf_tag(dw_die) == DW_TAG_subprogram &&

		dwarf_attr(dw_die, DW_AT_declaration, &attr) == NULL);

}



/**

 * die_get_data_member_location - Get the data-member offset

 * @mb_die: a DIE of a member of a data structure
@@ -392,6 +407,10 @@ static int __die_search_func_cb(Dwarf_Die *fn_die, void *data) 
{

	struct __addr_die_search_param *ad = data;



	/*

	 * Since a declaration entry doesn't has given pc, this always returns

	 * function definition entry.

	 */

	if (dwarf_tag(fn_die) == DW_TAG_subprogram &&

	    dwarf_haspc(fn_die, ad->addr)) {

		memcpy(ad->die_mem, fn_die, sizeof(Dwarf_Die));

tools/perf/util/dwarf-aux.h

+3 −0
Original line number Diff line number Diff line
@@ -38,6 +38,9 @@ extern int cu_find_lineinfo(Dwarf_Die *cudie, unsigned long addr, 
extern int cu_walk_functions_at(Dwarf_Die *cu_die, Dwarf_Addr addr,

			int (*callback)(Dwarf_Die *, void *), void *data);



/* Ensure that this DIE is a subprogram and definition (not declaration) */

extern bool die_is_func_def(Dwarf_Die *dw_die);



/* Compare diename and tname */

extern bool die_compare_name(Dwarf_Die *dw_die, const char *tname);

tools/perf/util/probe-finder.c

+5 −7
Original line number Diff line number Diff line
@@ -734,7 +734,7 @@ static int call_probe_finder(Dwarf_Die *sc_die, struct probe_finder *pf) 
	}



	/* If not a real subprogram, find a real one */

	if (dwarf_tag(sc_die) != DW_TAG_subprogram) {

	if (!die_is_func_def(sc_die)) {

		if (!die_find_realfunc(&pf->cu_die, pf->addr, &pf->sp_die)) {

			pr_warning("Failed to find probe point in any "

				   "functions.\n");
@@ -980,12 +980,10 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data) 
	struct dwarf_callback_param *param = data;

	struct probe_finder *pf = param->data;

	struct perf_probe_point *pp = &pf->pev->point;

	Dwarf_Attribute attr;



	/* Check tag and diename */

	if (dwarf_tag(sp_die) != DW_TAG_subprogram ||

	    !die_compare_name(sp_die, pp->function) ||

	    dwarf_attr(sp_die, DW_AT_declaration, &attr))

	if (!die_is_func_def(sp_die) ||

	    !die_compare_name(sp_die, pp->function))

		return DWARF_CB_OK;



	/* Check declared file */
@@ -1474,7 +1472,7 @@ static int line_range_inline_cb(Dwarf_Die *in_die, void *data) 
	return 0;

}



/* Search function from function name */

/* Search function definition from function name */

static int line_range_search_cb(Dwarf_Die *sp_die, void *data)

{

	struct dwarf_callback_param *param = data;
@@ -1485,7 +1483,7 @@ static int line_range_search_cb(Dwarf_Die *sp_die, void *data) 
	if (lr->file && strtailcmp(lr->file, dwarf_decl_file(sp_die)))

		return DWARF_CB_OK;



	if (dwarf_tag(sp_die) == DW_TAG_subprogram &&

	if (die_is_func_def(sp_die) &&

	    die_compare_name(sp_die, lr->function)) {

		lf->fname = dwarf_decl_file(sp_die);

		dwarf_decl_line(sp_die, &lr->offset);

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