diff options
| -rw-r--r-- | arch/arm/kernel/Makefile | 5 | ||||
| -rw-r--r-- | arch/arm/kernel/ftrace.c | 61 | ||||
| -rw-r--r-- | arch/arm/kernel/insn.c | 61 | ||||
| -rw-r--r-- | arch/arm/kernel/insn.h | 19 |
4 files changed, 87 insertions, 59 deletions
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 43b740d0e37..dd3d5f16c14 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -7,6 +7,7 @@ AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET) ifdef CONFIG_FUNCTION_TRACER CFLAGS_REMOVE_ftrace.o = -pg +CFLAGS_REMOVE_insn.o = -pg endif CFLAGS_REMOVE_return_address.o = -pg @@ -34,8 +35,8 @@ obj-$(CONFIG_HAVE_SCHED_CLOCK) += sched_clock.o obj-$(CONFIG_SMP) += smp.o smp_tlb.o obj-$(CONFIG_HAVE_ARM_SCU) += smp_scu.o obj-$(CONFIG_HAVE_ARM_TWD) += smp_twd.o -obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o -obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o +obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o insn.o +obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o insn.o obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o obj-$(CONFIG_KPROBES) += kprobes.o kprobes-common.o ifdef CONFIG_THUMB2_KERNEL diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c index 5c9cecfaeb2..df0bf0c8cb7 100644 --- a/arch/arm/kernel/ftrace.c +++ b/arch/arm/kernel/ftrace.c @@ -19,6 +19,8 @@ #include <asm/opcodes.h> #include <asm/ftrace.h> +#include "insn.h" + #ifdef CONFIG_THUMB2_KERNEL #define NOP 0xf85deb04 /* pop.w {lr} */ #else @@ -61,64 +63,9 @@ static unsigned long adjust_address(struct dyn_ftrace *rec, unsigned long addr) } #endif -#ifdef CONFIG_THUMB2_KERNEL -static unsigned long ftrace_gen_branch(unsigned long pc, unsigned long addr, - bool link) -{ - 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 = 0x9000 | (j1 << 13) | (j2 << 11) | imm11; - if (link) - second |= 1 << 14; - - return __opcode_thumb32_compose(first, second); -} -#else -static unsigned long ftrace_gen_branch(unsigned long pc, unsigned long addr, - bool link) -{ - unsigned long opcode = 0xea000000; - long offset; - - if (link) - opcode |= 1 << 24; - - offset = (long)addr - (long)(pc + 8); - if (unlikely(offset < -33554432 || offset > 33554428)) { - /* Can't generate branches that far (from ARM ARM). Ftrace - * doesn't generate branches outside of kernel text. - */ - WARN_ON_ONCE(1); - return 0; - } - - offset = (offset >> 2) & 0x00ffffff; - - return opcode | offset; -} -#endif - static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr) { - return ftrace_gen_branch(pc, addr, true); + return arm_gen_branch_link(pc, addr); } static int ftrace_modify_code(unsigned long pc, unsigned long old, @@ -258,7 +205,7 @@ static int __ftrace_modify_caller(unsigned long *callsite, { unsigned long caller_fn = (unsigned long) func; unsigned long pc = (unsigned long) callsite; - unsigned long branch = ftrace_gen_branch(pc, caller_fn, false); + unsigned long branch = arm_gen_branch(pc, caller_fn); unsigned long nop = 0xe1a00000; /* mov r0, r0 */ unsigned long old = enable ? nop : branch; unsigned long new = enable ? branch : nop; diff --git a/arch/arm/kernel/insn.c b/arch/arm/kernel/insn.c new file mode 100644 index 00000000000..ab312e51654 --- /dev/null +++ b/arch/arm/kernel/insn.c @@ -0,0 +1,61 @@ +#include <linux/kernel.h> +#include <asm/opcodes.h> + +static unsigned long +__arm_gen_branch_thumb2(unsigned long pc, unsigned long addr, bool link) +{ + 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 = 0x9000 | (j1 << 13) | (j2 << 11) | imm11; + if (link) + second |= 1 << 14; + + return __opcode_thumb32_compose(first, second); +} + +static unsigned long +__arm_gen_branch_arm(unsigned long pc, unsigned long addr, bool link) +{ + unsigned long opcode = 0xea000000; + long offset; + + if (link) + opcode |= 1 << 24; + + offset = (long)addr - (long)(pc + 8); + if (unlikely(offset < -33554432 || offset > 33554428)) { + WARN_ON_ONCE(1); + return 0; + } + + offset = (offset >> 2) & 0x00ffffff; + + return opcode | offset; +} + +unsigned long +__arm_gen_branch(unsigned long pc, unsigned long addr, bool link) +{ + if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) + return __arm_gen_branch_thumb2(pc, addr, link); + else + return __arm_gen_branch_arm(pc, addr, link); +} diff --git a/arch/arm/kernel/insn.h b/arch/arm/kernel/insn.h new file mode 100644 index 00000000000..994d60fd3ff --- /dev/null +++ b/arch/arm/kernel/insn.h @@ -0,0 +1,19 @@ +#ifndef __ASM_ARM_INSN_H +#define __ASM_ARM_INSN_H + +unsigned long +__arm_gen_branch(unsigned long pc, unsigned long addr, bool link); + +static inline unsigned long +arm_gen_branch(unsigned long pc, unsigned long addr) +{ + return __arm_gen_branch(pc, addr, false); +} + +static inline unsigned long +arm_gen_branch_link(unsigned long pc, unsigned long addr) +{ + return __arm_gen_branch(pc, addr, true); +} + +#endif |