From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
From: Joe Lawrence <joe.lawrence@xxxxxxxxxx>
commit 9c8e2f6d3d361439cc6744a094f1c15681b55269 upstream.
When building with -ffunction-sections, the compiler will place each
function into its own ELF section, prefixed with ".text". For example,
a simple test module with functions test_module_do_work() and
test_module_wq_func():
% objdump --section-headers test_module.o | awk '/\.text/{print $2}'
.text
.text.test_module_do_work
.text.test_module_wq_func
.init.text
.exit.text
Adjust the recordmcount scripts to look for ".text" as a section name
prefix. This will ensure that those functions will be included in the
__mcount_loc relocations:
% objdump --reloc --section __mcount_loc test_module.o
OFFSET TYPE VALUE
0000000000000000 R_X86_64_64 .text.test_module_do_work
0000000000000008 R_X86_64_64 .text.test_module_wq_func
0000000000000010 R_X86_64_64 .init.text
Link: http://lkml.kernel.org/r/1542745158-25392-2-git-send-email-joe.lawrence@xxxxxxxxxx
Signed-off-by: Joe Lawrence <joe.lawrence@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Cc: Manoj Gupta <manojgupta@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
scripts/recordmcount.c | 2 +-
scripts/recordmcount.pl | 13 +++++++++++++
2 files changed, 14 insertions(+), 1 deletion(-)
--- a/scripts/recordmcount.c
+++ b/scripts/recordmcount.c
@@ -415,7 +415,7 @@ static uint32_t (*w2)(uint16_t);
static int
is_mcounted_section_name(char const *const txtname)
{
- return strcmp(".text", txtname) == 0 ||
+ return strncmp(".text", txtname, 5) == 0 ||
strcmp(".init.text", txtname) == 0 ||
strcmp(".ref.text", txtname) == 0 ||
strcmp(".sched.text", txtname) == 0 ||
--- a/scripts/recordmcount.pl
+++ b/scripts/recordmcount.pl
@@ -142,6 +142,11 @@ my %text_sections = (
".text.unlikely" => 1,
);
+# Acceptable section-prefixes to record.
+my %text_section_prefixes = (
+ ".text." => 1,
+);
+
# Note: we are nice to C-programmers here, thus we skip the '||='-idiom.
$objdump = 'objdump' if (!$objdump);
$objcopy = 'objcopy' if (!$objcopy);
@@ -507,6 +512,14 @@ while (<IN>) {
# Only record text sections that we know are safe
$read_function = defined($text_sections{$1});
+ if (!$read_function) {
+ foreach my $prefix (keys %text_section_prefixes) {
+ if (substr($1, 0, length $prefix) eq $prefix) {
+ $read_function = 1;
+ last;
+ }
+ }
+ }
# print out any recorded offsets
update_funcs();
