diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index d203dbfa80370fcd44b11682e4d539392600da08..af6940c5b272a75a84f20668369f16543c3d5d88 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -7,6 +7,8 @@ config MIPS
select HAVE_ARCH_KGDB
select HAVE_FUNCTION_TRACER
select HAVE_FUNCTION_TRACE_MCOUNT_TEST
+ select HAVE_DYNAMIC_FTRACE
+ select HAVE_FTRACE_MCOUNT_RECORD
# Horrible source of confusion. Die, die, die ...
select EMBEDDED
select RTC_LIB if !MACH_LOONGSON
diff --git a/arch/mips/include/asm/ftrace.h b/arch/mips/include/asm/ftrace.h
index 5f8ebcf9fa614a930ae04c51ab625ef49b4a46c0..7094a40b96d8cea1184cf617894f67bee9a9e1f6 100644
--- a/arch/mips/include/asm/ftrace.h
+++ b/arch/mips/include/asm/ftrace.h
@@ -19,6 +19,15 @@
extern void _mcount(void);
#define mcount _mcount
+#ifdef CONFIG_DYNAMIC_FTRACE
+static inline unsigned long ftrace_call_adjust(unsigned long addr)
+{
+ return addr;
+}
+
+struct dyn_arch_ftrace {
+};
+#endif /* CONFIG_DYNAMIC_FTRACE */
#endif /* __ASSEMBLY__ */
#endif /* CONFIG_FUNCTION_TRACER */
#endif /* _ASM_MIPS_FTRACE_H */
diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
index 1340ba3dd38d916f2e2b22a01ffdf7918cfb96b7..8dda214632266bf23c09757cc477418b124587ef 100644
--- a/arch/mips/kernel/Makefile
+++ b/arch/mips/kernel/Makefile
@@ -11,6 +11,7 @@ obj-y += cpu-probe.o branch.o entry.o genex.o irq.o process.o \
time.o topology.o traps.o unaligned.o watch.o
ifdef CONFIG_FUNCTION_TRACER
+CFLAGS_REMOVE_ftrace.o = -pg
CFLAGS_REMOVE_early_printk.o = -pg
endif
@@ -31,7 +32,7 @@ obj-$(CONFIG_SYNC_R4K) += sync-r4k.o
obj-$(CONFIG_STACKTRACE) += stacktrace.o
obj-$(CONFIG_MODULES) += mips_ksyms.o module.o
-obj-$(CONFIG_FUNCTION_TRACER) += mcount.o
+obj-$(CONFIG_FUNCTION_TRACER) += mcount.o ftrace.o
obj-$(CONFIG_CPU_LOONGSON2) += r4k_fpu.o r4k_switch.o
obj-$(CONFIG_CPU_MIPS32) += r4k_fpu.o r4k_switch.o
diff --git a/arch/mips/kernel/ftrace.c b/arch/mips/kernel/ftrace.c
new file mode 100644
index 0000000000000000000000000000000000000000..5459a7838370557c41ba0689920da3b878a477a8
--- /dev/null
+++ b/arch/mips/kernel/ftrace.c
@@ -0,0 +1,112 @@
+/*
+ * Code for replacing ftrace calls with jumps.
+ *
+ * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
+ * Copyright (C) 2009 DSLab, Lanzhou University, China
+ * Author: Wu Zhangjin <wuzj@lemote.com>
+ *
+ * Thanks goes to Steven Rostedt for writing the original x86 version.
+ */
+
+#include <linux/uaccess.h>
+#include <linux/init.h>
+#include <linux/ftrace.h>
+
+#include <asm/cacheflush.h>
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+#define JAL 0x0c000000 /* jump & link: ip --> ra, jump to target */
+#define ADDR_MASK 0x03ffffff /* op_code|addr : 31...26|25 ....0 */
+#define jump_insn_encode(op_code, addr) \
+ ((unsigned int)((op_code) | (((addr) >> 2) & ADDR_MASK)))
+
+static unsigned int ftrace_nop = 0x00000000;
+
+static int ftrace_modify_code(unsigned long ip, unsigned int new_code)
+{
+ *(unsigned int *)ip = new_code;
+
+ flush_icache_range(ip, ip + 8);
+
+ return 0;
+}
+
+static int lui_v1;
+static int jal_mcount;
+
+int ftrace_make_nop(struct module *mod,
+ struct dyn_ftrace *rec, unsigned long addr)
+{
+ unsigned int new;
+ 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 & 0x40000000) {
+ /* record it for ftrace_make_call */
+ if (lui_v1 == 0)
+ lui_v1 = *(unsigned int *)ip;
+
+ /* lui v1, hi_16bit_of_mcount --> b 1f (0x10000004)
+ * addiu v1, v1, low_16bit_of_mcount
+ * move at, ra
+ * jalr v1
+ * nop
+ * 1f: (ip + 12)
+ */
+ new = 0x10000004;
+ } else {
+ /* record/calculate it for ftrace_make_call */
+ if (jal_mcount == 0) {
+ /* We can record it directly like this:
+ * jal_mcount = *(unsigned int *)ip;
+ * Herein, jump over the first two nop instructions */
+ jal_mcount = jump_insn_encode(JAL, (MCOUNT_ADDR + 8));
+ }
+
+ /* move at, ra
+ * jalr v1 --> nop
+ */
+ new = ftrace_nop;
+ }
+ return ftrace_modify_code(ip, new);
+}
+
+static int modified; /* initialized as 0 by default */
+
+int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
+{
+ unsigned int new;
+ unsigned long ip = rec->ip;
+
+ /* We just need to remove the "b ftrace_stub" at the fist time! */
+ if (modified == 0) {
+ modified = 1;
+ ftrace_modify_code(addr, ftrace_nop);
+ }
+ /* ip, module: 0xc0000000, kernel: 0x80000000 */
+ new = (ip & 0x40000000) ? lui_v1 : jal_mcount;
+
+ return ftrace_modify_code(ip, new);
+}
+
+#define FTRACE_CALL_IP ((unsigned long)(&ftrace_call))
+
+int ftrace_update_ftrace_func(ftrace_func_t func)
+{
+ unsigned int new;
+
+ new = jump_insn_encode(JAL, (unsigned long)func);
+
+ return ftrace_modify_code(FTRACE_CALL_IP, new);
+}
+
+int __init ftrace_dyn_arch_init(void *data)
+{
+ /* The return code is retured via data */
+ *(unsigned long *)data = 0;
+
+ return 0;
+}
+#endif /* CONFIG_DYNAMIC_FTRACE */
diff --git a/arch/mips/kernel/mcount.S b/arch/mips/kernel/mcount.S
index cbb45edad4646252f967c81dbb90efc8c4446fdf..ffc425979d4fa9d1b9781c2f6ad3609d5370414c 100644
--- a/arch/mips/kernel/mcount.S
+++ b/arch/mips/kernel/mcount.S
@@ -58,6 +58,33 @@
move ra, AT
.endm
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+NESTED(ftrace_caller, PT_SIZE, ra)
+ .globl _mcount
+_mcount:
+ b ftrace_stub
+ nop
+ lw t0, function_trace_stop
+ bnez t0, ftrace_stub
+ nop
+
+ MCOUNT_SAVE_REGS
+
+ move a0, ra /* arg1: next ip, selfaddr */
+ .globl ftrace_call
+ftrace_call:
+ nop /* a placeholder for the call to a real tracing function */
+ move a1, AT /* arg2: the caller's next ip, parent */
+
+ MCOUNT_RESTORE_REGS
+ .globl ftrace_stub
+ftrace_stub:
+ RETURN_BACK
+ END(ftrace_caller)
+
+#else /* ! CONFIG_DYNAMIC_FTRACE */
+
NESTED(_mcount, PT_SIZE, ra)
lw t0, function_trace_stop
bnez t0, ftrace_stub
@@ -82,5 +109,7 @@ ftrace_stub:
RETURN_BACK
END(_mcount)
+#endif /* ! CONFIG_DYNAMIC_FTRACE */
+
.set at
.set reorder
diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl
index ab368e8a007d78f13ed5a8adfb957a2d3a2af2bb..92f09fe9639ecdab0884330d049ae6b391765be7 100755
--- a/scripts/recordmcount.pl
+++ b/scripts/recordmcount.pl
@@ -295,6 +295,58 @@ if ($arch eq "x86_64") {
$ld .= " -m elf64_sparc";
$cc .= " -m64";
$objcopy .= " -O elf64-sparc";
+} elsif ($arch eq "mips") {
+ # To enable module support, we need to enable the -mlong-calls option
+ # of gcc for module, after using this option, we can not get the real
+ # offset of the calling to _mcount, but the offset of the lui
+ # instruction or the addiu one. herein, we record the address of the
+ # first one, and then we can replace this instruction by a branch
+ # instruction to jump over the profiling function to filter the
+ # indicated functions, or swith back to the lui instruction to trace
+ # them, which means dynamic tracing.
+ #
+ # c: 3c030000 lui v1,0x0
+ # c: R_MIPS_HI16 _mcount
+ # c: R_MIPS_NONE *ABS*
+ # c: R_MIPS_NONE *ABS*
+ # 10: 64630000 daddiu v1,v1,0
+ # 10: R_MIPS_LO16 _mcount
+ # 10: R_MIPS_NONE *ABS*
+ # 10: R_MIPS_NONE *ABS*
+ # 14: 03e0082d move at,ra
+ # 18: 0060f809 jalr v1
+ #
+ # for the kernel:
+ #
+ # 10: 03e0082d move at,ra
+ # 14: 0c000000 jal 0 <loongson_halt>
+ # 14: R_MIPS_26 _mcount
+ # 14: R_MIPS_NONE *ABS*
+ # 14: R_MIPS_NONE *ABS*
+ # 18: 00020021 nop
+ if ($is_module eq "0") {
+ $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s_mcount\$";
+ } else {
+ $mcount_regex = "^\\s*([0-9a-fA-F]+): R_MIPS_HI16\\s+_mcount\$";
+ }
+ $objdump .= " -Melf-trad".$endian."mips ";
+
+ if ($endian eq "big") {
+ $endian = " -EB ";
+ $ld .= " -melf".$bits."btsmip";
+ } else {
+ $endian = " -EL ";
+ $ld .= " -melf".$bits."ltsmip";
+ }
+
+ $cc .= " -mno-abicalls -fno-pic -mabi=" . $bits . $endian;
+ $ld .= $endian;
+
+ if ($bits == 64) {
+ $function_regex =
+ "^([0-9a-fA-F]+)\\s+<(.|[^\$]L.*?|\$[^L].*?|[^\$][^L].*?)>:";
+ $type = ".dword";
+ }
} elsif ($arch eq "microblaze") {
# Microblaze calls '_mcount' instead of plain 'mcount'.
$mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s_mcount\$";