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authorRabin Vincent <rabin@rab.in>2012-02-18 17:50:06 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2012-03-24 09:38:55 +0000
commitd82227cf8f0b42ff42c21ed47025fdf54cb1698d (patch)
tree7f2501ef1f17a4fad5febe4b6a524d0e28eff43e /arch/arm/kernel/ftrace.c
parent4394e2824c8d97d81a336edb469b13c8806604e4 (diff)
downloadop-kernel-dev-d82227cf8f0b42ff42c21ed47025fdf54cb1698d.zip
op-kernel-dev-d82227cf8f0b42ff42c21ed47025fdf54cb1698d.tar.gz
ARM: 7331/1: extract out insn generation code from ftrace
Extract out the instruction generation code so that it can be used for jump labels too. Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/kernel/ftrace.c')
-rw-r--r--arch/arm/kernel/ftrace.c61
1 files changed, 4 insertions, 57 deletions
diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c
index 5c9cecf..df0bf0c 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;
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