Message ID | 20210312221749.1248947-1-manojgupta@google.com |
---|---|
State | New |
Headers | show |
Series | [v2] scripts/recordmcount.{c,pl}: support -ffunction-sections .text.* section names | expand |
On Fri, Mar 12, 2021 at 02:17:49PM -0800, Manoj Gupta wrote: > From: Joe Lawrence <joe.lawrence@redhat.com> > > 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@redhat.com > > Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com> > Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> > > [Manoj: Resolve conflict on 4.4.y/4.9.y because of missing 42c269c88dc1] > Signed-off-by: Manoj Gupta <manojgupta@google.com> > --- > > Changes v1 -> v2: > Change "nc" to "Manoj" Now queued up, thanks. greg k-h
diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c index 7250fb38350c..8cba4c44da4c 100644 --- a/scripts/recordmcount.c +++ b/scripts/recordmcount.c @@ -362,7 +362,7 @@ 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(".ref.text", txtname) == 0 || strcmp(".sched.text", txtname) == 0 || strcmp(".spinlock.text", txtname) == 0 || diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl index ccd6614ea218..5ca4ec297019 100755 --- a/scripts/recordmcount.pl +++ b/scripts/recordmcount.pl @@ -138,6 +138,11 @@ 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); @@ -503,6 +508,14 @@ 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();