diff options
| author | Rabin Vincent <rabin@rab.in> | 2010-08-10 19:52:35 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-09-02 15:28:43 +0100 |
| commit | 72dc43a9eb123d2742bd413c80dbeab0c588f622 (patch) | |
| tree | d4a020340a00fc00497aedef1fcd8c6bd8abaad7 /arch | |
| parent | 3b6c223b1b97ad60bbb0f4efda57d649414ac2a2 (diff) | |
| download | linux-72dc43a9eb123d2742bd413c80dbeab0c588f622.tar.bz2 | |
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 <catalin.marinas@arm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org> [recordmcount.pl change]
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/include/asm/ftrace.h | 3 | ||||
| -rw-r--r-- | arch/arm/kernel/ftrace.c | 33 |
2 files changed, 35 insertions, 1 deletions
diff --git a/arch/arm/include/asm/ftrace.h b/arch/arm/include/asm/ftrace.h index 4a56a2ee067c..f89515adac60 100644 --- a/arch/arm/include/asm/ftrace.h +++ b/arch/arm/include/asm/ftrace.h @@ -18,7 +18,8 @@ struct dyn_arch_ftrace { static inline unsigned long ftrace_call_adjust(unsigned long addr) { - return addr; + /* With Thumb-2, the recorded addresses have the lsb set */ + return addr & ~1; } extern void ftrace_caller_old(void); diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c index f09014cfbf2c..971ac8c36ea7 100644 --- a/arch/arm/kernel/ftrace.c +++ b/arch/arm/kernel/ftrace.c @@ -18,7 +18,11 @@ #include <asm/cacheflush.h> #include <asm/ftrace.h> +#ifdef CONFIG_THUMB2_KERNEL +#define NOP 0xeb04f85d /* pop.w {lr} */ +#else #define NOP 0xe8bd4000 /* pop {lr} */ +#endif #ifdef CONFIG_OLD_MCOUNT #define OLD_MCOUNT_ADDR ((unsigned long) mcount) @@ -56,6 +60,34 @@ static unsigned long adjust_address(struct dyn_ftrace *rec, unsigned long addr) #endif /* construct a branch (BL) instruction to addr */ +#ifdef CONFIG_THUMB2_KERNEL +static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr) +{ + unsigned long s, j1, j2, i1, i2, imm10, imm11; + unsigned long first, second; + long offset; + + offset = (long)addr - (long)(pc + 4); + if (offset < -16777216 || offset > 16777214) { + WARN_ON_ONCE(1); + return 0; + } + + s = (offset >> 24) & 0x1; + i1 = (offset >> 23) & 0x1; + i2 = (offset >> 22) & 0x1; + imm10 = (offset >> 12) & 0x3ff; + imm11 = (offset >> 1) & 0x7ff; + + j1 = (!i1) ^ s; + j2 = (!i2) ^ s; + + first = 0xf000 | (s << 10) | imm10; + second = 0xd000 | (j1 << 13) | (j2 << 11) | imm11; + + return (second << 16) | first; +} +#else static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr) { long offset; @@ -73,6 +105,7 @@ static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr) return 0xeb000000 | offset; } +#endif static int ftrace_modify_code(unsigned long pc, unsigned long old, unsigned long new) |