From 4161c8b2a1e5c93146fc6e9a638c018a14648c6b Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Fri, 7 Nov 2008 13:26:25 +0000 Subject: [PATCH] ftrace: Align __mcount_loc sections Align the __mcount_loc sections so that architectures with strict alignment requirements need not worry about performing unaligned accesses. This fixes an issue where I was seeing unaligned accesses, which are not supported on our architecture (the results of an unaligned access are undefined). Signed-off-by: Matt Fleming --- scripts/recordmcount.pl | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl index 6b9fe3e..2d0bfa1 100755 --- a/scripts/recordmcount.pl +++ b/scripts/recordmcount.pl @@ -134,6 +134,7 @@ my $section_regex; # Find the start of a section my $function_regex; # Find the name of a function # (return offset and func name) my $mcount_regex; # Find the call site to mcount (return offset) +my $alignment; # The .align value to use for $mcount_section if ($arch eq "x86") { if ($bits == 64) { @@ -148,6 +149,7 @@ if ($arch eq "x86_64") { $function_regex = "^([0-9a-fA-F]+)\\s+<(.*?)>:"; $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\smcount([+-]0x[0-9a-zA-Z]+)?\$"; $type = ".quad"; + $alignment = 8; # force flags for this arch $ld .= " -m elf_x86_64"; @@ -160,6 +162,7 @@ if ($arch eq "x86_64") { $function_regex = "^([0-9a-fA-F]+)\\s+<(.*?)>:"; $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\smcount\$"; $type = ".long"; + $alignment = 4; # force flags for this arch $ld .= " -m elf_i386"; @@ -288,6 +291,7 @@ sub update_funcs open(FILE, ">$mcount_s") || die "can't create $mcount_s\n"; $opened = 1; print FILE "\t.section $mcount_section,\"a\",\@progbits\n"; + print FILE "\t.align $alignment\n"; } printf FILE "\t%s %s + %d\n", $type, $ref_func, $offsets[$i] - $offset; } -- 1.5.6.4