perf probe: Fix to find range-only function instance

Fix die_is_func_instance() to find range-only function instance.

In some case, a function instance can be made without any low PC or
entry PC, but only with address ranges by optimization.  (e.g. cold text
partially in "text.unlikely" section) To find such function instance, we
have to check the range attribute too.

Fixes: e1ecbbc3fa ("perf probe: Fix to handle optimized not-inlined functions")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/157190835669.1859.8368628035930950596.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Masami Hiramatsu 2019-10-24 18:12:36 +09:00 committed by Arnaldo Carvalho de Melo
parent 4bfbcf3ee1
commit b77afa1f81

View File

@ -318,10 +318,14 @@ bool die_is_func_def(Dwarf_Die *dw_die)
bool die_is_func_instance(Dwarf_Die *dw_die)
{
Dwarf_Addr tmp;
Dwarf_Attribute attr_mem;
/* Actually gcc optimizes non-inline as like as inlined */
return !dwarf_func_inline(dw_die) && dwarf_entrypc(dw_die, &tmp) == 0;
return !dwarf_func_inline(dw_die) &&
(dwarf_entrypc(dw_die, &tmp) == 0 ||
dwarf_attr(dw_die, DW_AT_ranges, &attr_mem) != NULL);
}
/**
* die_get_data_member_location - Get the data-member offset
* @mb_die: a DIE of a member of a data structure