Commit 378eeaad authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Arnaldo Carvalho de Melo
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perf probe: Fix local variable searching loop



Fix to check the die's address and search into the die only if it has given
address.

This will avoid finding wrong variables in wrong basic block.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20101021101309.3542.46434.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: default avatarMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 4046b8bb
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+18 −8
Original line number Original line Diff line number Diff line
@@ -329,25 +329,35 @@ static Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
	return die_find_child(sp_die, __die_find_inline_cb, &addr, die_mem);
	return die_find_child(sp_die, __die_find_inline_cb, &addr, die_mem);
}
}


struct __find_variable_param {
	const char *name;
	Dwarf_Addr addr;
};

static int __die_find_variable_cb(Dwarf_Die *die_mem, void *data)
static int __die_find_variable_cb(Dwarf_Die *die_mem, void *data)
{
{
	const char *name = data;
	struct __find_variable_param *fvp = data;
	int tag;
	int tag;


	tag = dwarf_tag(die_mem);
	tag = dwarf_tag(die_mem);
	if ((tag == DW_TAG_formal_parameter ||
	if ((tag == DW_TAG_formal_parameter ||
	     tag == DW_TAG_variable) &&
	     tag == DW_TAG_variable) &&
	    die_compare_name(die_mem, name))
	    die_compare_name(die_mem, fvp->name))
		return DIE_FIND_CB_FOUND;
		return DIE_FIND_CB_FOUND;


	if (dwarf_haspc(die_mem, fvp->addr))
		return DIE_FIND_CB_CONTINUE;
		return DIE_FIND_CB_CONTINUE;
	else
		return DIE_FIND_CB_SIBLING;
}
}


/* Find a variable called 'name' */
/* Find a variable called 'name' at given address */
static Dwarf_Die *die_find_variable(Dwarf_Die *sp_die, const char *name,
static Dwarf_Die *die_find_variable_at(Dwarf_Die *sp_die, const char *name,
				    Dwarf_Die *die_mem)
				       Dwarf_Addr addr, Dwarf_Die *die_mem)
{
{
	return die_find_child(sp_die, __die_find_variable_cb, (void *)name,
	struct __find_variable_param fvp = { .name = name, .addr = addr};

	return die_find_child(sp_die, __die_find_variable_cb, (void *)&fvp,
			      die_mem);
			      die_mem);
}
}


@@ -731,7 +741,7 @@ static int find_variable(Dwarf_Die *sp_die, struct probe_finder *pf)
	pr_debug("Searching '%s' variable in context.\n",
	pr_debug("Searching '%s' variable in context.\n",
		 pf->pvar->var);
		 pf->pvar->var);
	/* Search child die for local variables and parameters. */
	/* Search child die for local variables and parameters. */
	if (die_find_variable(sp_die, pf->pvar->var, &vr_die))
	if (die_find_variable_at(sp_die, pf->pvar->var, pf->addr, &vr_die))
		ret = convert_variable(&vr_die, pf);
		ret = convert_variable(&vr_die, pf);
	else {
	else {
		/* Search upper class */
		/* Search upper class */