From a484e54fae891703cbe1c9ec1b536605f11f5482 Mon Sep 17 00:00:00 2001 From: David Daney Date: Fri, 9 Jul 2010 14:52:05 -0700 Subject: tracing: Fix $mcount_regex for MIPS in recordmcount.pl I found this issue in a locally patched 2.6.32.x, current kernels have moved the offending code to an __init function which is skipped by recordmcount.pl, so the bug is not currently being exercised. However, I think the patch is still a good idea, to avoid future problems if _mcount were to ever have its address taken in normal code. This is what I originally saw: Although arch/mips/kernel/ftrace.c is built without -pg, and thus contains no calls to _mcount, it does use the address of _mcount in ftrace_make_nop(). This was causing relocations to be emitted for _mcount which recordmcount.pl erronously took to be _mcount call sites. The result was that the text of ftrace_make_nop() would be patched with garbage leading to a system crash. In non-module code, all _mcount call sites will have R_MIPS_26 relocations, so we restrict $mcount_regex to only match on these. Acked-by: Ralf Baechle Acked-by: Wu Zhangjin Signed-off-by: David Daney LKML-Reference: <1278712325-12050-1-git-send-email-ddaney@caviumnetworks.com> Cc: Li Hong Cc: Ingo Molnar Cc: Matt Fleming Signed-off-by: Steven Rostedt --- scripts/recordmcount.pl | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/recordmcount.pl') diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl index f3c9c0a..0171060 100755 --- a/scripts/recordmcount.pl +++ b/scripts/recordmcount.pl @@ -326,7 +326,7 @@ if ($arch eq "x86_64") { # 14: R_MIPS_NONE *ABS* # 18: 00020021 nop if ($is_module eq "0") { - $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s_mcount\$"; + $mcount_regex = "^\\s*([0-9a-fA-F]+): R_MIPS_26\\s+_mcount\$"; } else { $mcount_regex = "^\\s*([0-9a-fA-F]+): R_MIPS_HI16\\s+_mcount\$"; } -- cgit v1.1 From 465c6cca2668a2db2a4ffce3dca5714017873f2b Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Fri, 6 Aug 2010 03:26:24 -0400 Subject: tracing: Extend recordmcount to better support Blackfin mcount The mcount call on Blackfin systems includes some stack manipulation around the actual call site, so extend the build time perl script to support this. This way we can avoid doing the calculation at runtime. Signed-off-by: Mike Frysinger LKML-Reference: <1281079584-21205-1-git-send-email-vapier@gentoo.org> Signed-off-by: Steven Rostedt --- scripts/recordmcount.pl | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'scripts/recordmcount.pl') diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl index f3c9c0a..2c56539 100755 --- a/scripts/recordmcount.pl +++ b/scripts/recordmcount.pl @@ -159,6 +159,7 @@ 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 $mcount_adjust; # Address adjustment to mcount offset my $alignment; # The .align value to use for $mcount_section my $section_type; # Section header plus possible alignment command my $can_use_local = 0; # If we can use local function references @@ -213,6 +214,7 @@ $section_regex = "Disassembly of section\\s+(\\S+):"; $function_regex = "^([0-9a-fA-F]+)\\s+<(.*?)>:"; $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\smcount\$"; $section_type = '@progbits'; +$mcount_adjust = 0; $type = ".long"; if ($arch eq "x86_64") { @@ -351,6 +353,9 @@ if ($arch eq "x86_64") { } elsif ($arch eq "microblaze") { # Microblaze calls '_mcount' instead of plain 'mcount'. $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s_mcount\$"; +} elsif ($arch eq "blackfin") { + $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s__mcount\$"; + $mcount_adjust = -4; } else { die "Arch $arch is not supported with CONFIG_FTRACE_MCOUNT_RECORD"; } @@ -511,7 +516,7 @@ while () { } # is this a call site to mcount? If so, record it to print later if ($text_found && /$mcount_regex/) { - push(@offsets, hex $1); + push(@offsets, (hex $1) + $mcount_adjust); } } -- cgit v1.1 From 3b6c223b1b97ad60bbb0f4efda57d649414ac2a2 Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Tue, 10 Aug 2010 19:43:28 +0100 Subject: ARM: 6318/1: ftrace: fix and update dynamic ftrace This adds mcount recording and updates dynamic ftrace for ARM to work with the new ftrace dyamic tracing implementation. It also adds support for the mcount format used by newer ARM compilers. With dynamic tracing, mcount() is implemented as a nop. Callsites are patched on startup with nops, and dynamically patched to call to the ftrace_caller() routine as needed. Acked-by: Steven Rostedt [recordmcount.pl change] Signed-off-by: Rabin Vincent Signed-off-by: Russell King --- scripts/recordmcount.pl | 2 ++ 1 file changed, 2 insertions(+) (limited to 'scripts/recordmcount.pl') diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl index e67f054..022d467 100755 --- a/scripts/recordmcount.pl +++ b/scripts/recordmcount.pl @@ -270,6 +270,8 @@ if ($arch eq "x86_64") { } elsif ($arch eq "arm") { $alignment = 2; $section_type = '%progbits'; + $mcount_regex = "^\\s*([0-9a-fA-F]+):\\s*R_ARM_(CALL|PC24)" . + "\\s+(__gnu_mcount_nc|mcount)\$"; } elsif ($arch eq "ia64") { $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s_mcount\$"; -- cgit v1.1 From 72dc43a9eb123d2742bd413c80dbeab0c588f622 Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Tue, 10 Aug 2010 19:52:35 +0100 Subject: ARM: 6319/1: ftrace: add Thumb-2 support to dynamic ftrace Handle the different nop and call instructions for Thumb-2. Also, we need to adjust the recorded mcount_loc addresses because they have the lsb set. Cc: Catalin Marinas Acked-by: Steven Rostedt [recordmcount.pl change] Signed-off-by: Rabin Vincent Signed-off-by: Russell King --- scripts/recordmcount.pl | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/recordmcount.pl') diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl index 022d467..1d7963f 100755 --- a/scripts/recordmcount.pl +++ b/scripts/recordmcount.pl @@ -270,7 +270,7 @@ if ($arch eq "x86_64") { } elsif ($arch eq "arm") { $alignment = 2; $section_type = '%progbits'; - $mcount_regex = "^\\s*([0-9a-fA-F]+):\\s*R_ARM_(CALL|PC24)" . + $mcount_regex = "^\\s*([0-9a-fA-F]+):\\s*R_ARM_(CALL|PC24|THM_CALL)" . "\\s+(__gnu_mcount_nc|mcount)\$"; } elsif ($arch eq "ia64") { -- cgit v1.1