diff options
| -rw-r--r-- | arch/mips/kernel/ftrace.c | 54 |
1 files changed, 27 insertions, 27 deletions
diff --git a/arch/mips/kernel/ftrace.c b/arch/mips/kernel/ftrace.c index 635c1dcdc4f..5970286131d 100644 --- a/arch/mips/kernel/ftrace.c +++ b/arch/mips/kernel/ftrace.c @@ -17,21 +17,7 @@ #include <asm/cacheflush.h> #include <asm/uasm.h> -/* - * If the Instruction Pointer is in module space (0xc0000000), return true; - * otherwise, it is in kernel space (0x80000000), return false. - * - * FIXME: This will not work when the kernel space and module space are the - * same. If they are the same, we need to modify scripts/recordmcount.pl, - * ftrace_make_nop/call() and the other related parts to ensure the - * enabling/disabling of the calling site to _mcount is right for both kernel - * and module. - */ - -static inline int in_module(unsigned long ip) -{ - return ip & 0x40000000; -} +#include <asm-generic/sections.h> #ifdef CONFIG_DYNAMIC_FTRACE @@ -69,6 +55,20 @@ static inline void ftrace_dyn_arch_init_insns(void) #endif } +/* + * Check if the address is in kernel space + * + * Clone core_kernel_text() from kernel/extable.c, but doesn't call + * init_kernel_text() for Ftrace doesn't trace functions in init sections. + */ +static inline int in_kernel_space(unsigned long ip) +{ + if (ip >= (unsigned long)_stext && + ip <= (unsigned long)_etext) + return 1; + return 0; +} + static int ftrace_modify_code(unsigned long ip, unsigned int new_code) { int faulted; @@ -91,10 +91,16 @@ int ftrace_make_nop(struct module *mod, unsigned long ip = rec->ip; /* - * We have compiled module with -mlong-calls, but compiled the kernel - * without it, we need to cope with them respectively. + * If ip is in kernel space, no long call, otherwise, long call is + * needed. */ - if (in_module(ip)) { + if (in_kernel_space(ip)) { + /* + * move at, ra + * jal _mcount --> nop + */ + new = INSN_NOP; + } else { #if defined(KBUILD_MCOUNT_RA_ADDRESS) && defined(CONFIG_32BIT) /* * lui v1, hi_16bit_of_mcount --> b 1f (0x10000005) @@ -117,12 +123,6 @@ int ftrace_make_nop(struct module *mod, */ new = INSN_B_1F_4; #endif - } else { - /* - * move at, ra - * jal _mcount --> nop - */ - new = INSN_NOP; } return ftrace_modify_code(ip, new); } @@ -132,8 +132,8 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) unsigned int new; unsigned long ip = rec->ip; - /* ip, module: 0xc0000000, kernel: 0x80000000 */ - new = in_module(ip) ? insn_lui_v1_hi16_mcount : insn_jal_ftrace_caller; + new = in_kernel_space(ip) ? insn_jal_ftrace_caller : + insn_lui_v1_hi16_mcount; return ftrace_modify_code(ip, new); } @@ -204,7 +204,7 @@ unsigned long ftrace_get_parent_addr(unsigned long self_addr, * instruction "lui v1, hi_16bit_of_mcount"(offset is 24), but for * kernel, move after the instruction "move ra, at"(offset is 16) */ - ip = self_addr - (in_module(self_addr) ? 24 : 16); + ip = self_addr - (in_kernel_space(self_addr) ? 16 : 24); /* * search the text until finding the non-store instruction or "s{d,w} |