entry_*.S now includes a lot more than just kernel entry/exit code. As a
first step at cleaning this up, let's split out the ftrace bits into
separate files. Also move all related tracing code into a new trace/
subdirectory.

No functional changes.

Suggested-by: Michael Ellerman <m...@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n....@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/Makefile                  |   9 +-
 arch/powerpc/kernel/entry_32.S                | 107 -------
 arch/powerpc/kernel/entry_64.S                | 378 -------------------------
 arch/powerpc/kernel/trace/Makefile            |  24 ++
 arch/powerpc/kernel/{ => trace}/ftrace.c      |   0
 arch/powerpc/kernel/trace/ftrace_32.S         | 118 ++++++++
 arch/powerpc/kernel/trace/ftrace_64.S         | 389 ++++++++++++++++++++++++++
 arch/powerpc/kernel/{ => trace}/trace_clock.c |   0
 8 files changed, 532 insertions(+), 493 deletions(-)
 create mode 100644 arch/powerpc/kernel/trace/Makefile
 rename arch/powerpc/kernel/{ => trace}/ftrace.c (100%)
 create mode 100644 arch/powerpc/kernel/trace/ftrace_32.S
 create mode 100644 arch/powerpc/kernel/trace/ftrace_64.S
 rename arch/powerpc/kernel/{ => trace}/trace_clock.c (100%)

diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 3e461637b64d..b9db46ae545b 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -25,8 +25,6 @@ CFLAGS_REMOVE_cputable.o = -mno-sched-epilog 
$(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_prom_init.o = -mno-sched-epilog $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_btext.o = -mno-sched-epilog $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_prom.o = -mno-sched-epilog $(CC_FLAGS_FTRACE)
-# do not trace tracer code
-CFLAGS_REMOVE_ftrace.o = -mno-sched-epilog $(CC_FLAGS_FTRACE)
 # timers used by tracing
 CFLAGS_REMOVE_time.o = -mno-sched-epilog $(CC_FLAGS_FTRACE)
 endif
@@ -119,10 +117,7 @@ obj64-$(CONFIG_AUDIT)              += compat_audit.o
 
 obj-$(CONFIG_PPC_IO_WORKAROUNDS)       += io-workarounds.o
 
-obj-$(CONFIG_DYNAMIC_FTRACE)   += ftrace.o
-obj-$(CONFIG_FUNCTION_GRAPH_TRACER)    += ftrace.o
-obj-$(CONFIG_FTRACE_SYSCALLS)  += ftrace.o
-obj-$(CONFIG_TRACING)          += trace_clock.o
+obj-y                          += trace/
 
 ifneq ($(CONFIG_PPC_INDIRECT_PIO),y)
 obj-y                          += iomap.o
@@ -143,8 +138,6 @@ obj-$(CONFIG_KVM_GUEST)             += kvm.o kvm_emul.o
 # Disable GCOV & sanitizers in odd or sensitive code
 GCOV_PROFILE_prom_init.o := n
 UBSAN_SANITIZE_prom_init.o := n
-GCOV_PROFILE_ftrace.o := n
-UBSAN_SANITIZE_ftrace.o := n
 GCOV_PROFILE_machine_kexec_64.o := n
 UBSAN_SANITIZE_machine_kexec_64.o := n
 GCOV_PROFILE_machine_kexec_32.o := n
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index a38600949f3a..8587059ad848 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -31,7 +31,6 @@
 #include <asm/ppc_asm.h>
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
-#include <asm/ftrace.h>
 #include <asm/ptrace.h>
 #include <asm/export.h>
 
@@ -1315,109 +1314,3 @@ machine_check_in_rtas:
        /* XXX load up BATs and panic */
 
 #endif /* CONFIG_PPC_RTAS */
-
-#ifdef CONFIG_FUNCTION_TRACER
-#ifdef CONFIG_DYNAMIC_FTRACE
-_GLOBAL(mcount)
-_GLOBAL(_mcount)
-       /*
-        * It is required that _mcount on PPC32 must preserve the
-        * link register. But we have r0 to play with. We use r0
-        * to push the return address back to the caller of mcount
-        * into the ctr register, restore the link register and
-        * then jump back using the ctr register.
-        */
-       mflr    r0
-       mtctr   r0
-       lwz     r0, 4(r1)
-       mtlr    r0
-       bctr
-
-_GLOBAL(ftrace_caller)
-       MCOUNT_SAVE_FRAME
-       /* r3 ends up with link register */
-       subi    r3, r3, MCOUNT_INSN_SIZE
-.globl ftrace_call
-ftrace_call:
-       bl      ftrace_stub
-       nop
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-.globl ftrace_graph_call
-ftrace_graph_call:
-       b       ftrace_graph_stub
-_GLOBAL(ftrace_graph_stub)
-#endif
-       MCOUNT_RESTORE_FRAME
-       /* old link register ends up in ctr reg */
-       bctr
-#else
-_GLOBAL(mcount)
-_GLOBAL(_mcount)
-
-       MCOUNT_SAVE_FRAME
-
-       subi    r3, r3, MCOUNT_INSN_SIZE
-       LOAD_REG_ADDR(r5, ftrace_trace_function)
-       lwz     r5,0(r5)
-
-       mtctr   r5
-       bctrl
-       nop
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-       b       ftrace_graph_caller
-#endif
-       MCOUNT_RESTORE_FRAME
-       bctr
-#endif
-EXPORT_SYMBOL(_mcount)
-
-_GLOBAL(ftrace_stub)
-       blr
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-_GLOBAL(ftrace_graph_caller)
-       /* load r4 with local address */
-       lwz     r4, 44(r1)
-       subi    r4, r4, MCOUNT_INSN_SIZE
-
-       /* Grab the LR out of the caller stack frame */
-       lwz     r3,52(r1)
-
-       bl      prepare_ftrace_return
-       nop
-
-        /*
-         * prepare_ftrace_return gives us the address we divert to.
-         * Change the LR in the callers stack frame to this.
-         */
-       stw     r3,52(r1)
-
-       MCOUNT_RESTORE_FRAME
-       /* old link register ends up in ctr reg */
-       bctr
-
-_GLOBAL(return_to_handler)
-       /* need to save return values */
-       stwu    r1, -32(r1)
-       stw     r3, 20(r1)
-       stw     r4, 16(r1)
-       stw     r31, 12(r1)
-       mr      r31, r1
-
-       bl      ftrace_return_to_handler
-       nop
-
-       /* return value has real return address */
-       mtlr    r3
-
-       lwz     r3, 20(r1)
-       lwz     r4, 16(r1)
-       lwz     r31,12(r1)
-       lwz     r1, 0(r1)
-
-       /* Jump back to real return address */
-       blr
-#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-#endif /* CONFIG_FUNCTION_TRACER */
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 70a5c1948b05..9b541d22595a 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -20,7 +20,6 @@
 
 #include <linux/errno.h>
 #include <linux/err.h>
-#include <linux/magic.h>
 #include <asm/unistd.h>
 #include <asm/processor.h>
 #include <asm/page.h>
@@ -33,7 +32,6 @@
 #include <asm/bug.h>
 #include <asm/ptrace.h>
 #include <asm/irqflags.h>
-#include <asm/ftrace.h>
 #include <asm/hw_irq.h>
 #include <asm/context_tracking.h>
 #include <asm/tm.h>
@@ -1173,379 +1171,3 @@ _GLOBAL(enter_prom)
        ld      r0,16(r1)
        mtlr    r0
         blr
-
-#ifdef CONFIG_FUNCTION_TRACER
-#ifdef CONFIG_DYNAMIC_FTRACE
-_GLOBAL(mcount)
-_GLOBAL(_mcount)
-EXPORT_SYMBOL(_mcount)
-       mflr    r12
-       mtctr   r12
-       mtlr    r0
-       bctr
-
-#ifndef CC_USING_MPROFILE_KERNEL
-_GLOBAL_TOC(ftrace_caller)
-       /* Taken from output of objdump from lib64/glibc */
-       mflr    r3
-       ld      r11, 0(r1)
-       stdu    r1, -112(r1)
-       std     r3, 128(r1)
-       ld      r4, 16(r11)
-       subi    r3, r3, MCOUNT_INSN_SIZE
-.globl ftrace_call
-ftrace_call:
-       bl      ftrace_stub
-       nop
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-.globl ftrace_graph_call
-ftrace_graph_call:
-       b       ftrace_graph_stub
-_GLOBAL(ftrace_graph_stub)
-#endif
-       ld      r0, 128(r1)
-       mtlr    r0
-       addi    r1, r1, 112
-
-#else /* CC_USING_MPROFILE_KERNEL */
-/*
- *
- * ftrace_caller() is the function that replaces _mcount() when ftrace is
- * active.
- *
- * We arrive here after a function A calls function B, and we are the trace
- * function for B. When we enter r1 points to A's stack frame, B has not yet
- * had a chance to allocate one yet.
- *
- * Additionally r2 may point either to the TOC for A, or B, depending on
- * whether B did a TOC setup sequence before calling us.
- *
- * On entry the LR points back to the _mcount() call site, and r0 holds the
- * saved LR as it was on entry to B, ie. the original return address at the
- * call site in A.
- *
- * Our job is to save the register state into a struct pt_regs (on the stack)
- * and then arrange for the ftrace function to be called.
- */
-_GLOBAL(ftrace_caller)
-       /* Save the original return address in A's stack frame */
-       std     r0,LRSAVE(r1)
-
-       /* Create our stack frame + pt_regs */
-       stdu    r1,-SWITCH_FRAME_SIZE(r1)
-
-       /* Save all gprs to pt_regs */
-       SAVE_8GPRS(0,r1)
-       SAVE_8GPRS(8,r1)
-       SAVE_8GPRS(16,r1)
-       SAVE_8GPRS(24,r1)
-
-       /* Load special regs for save below */
-       mfmsr   r8
-       mfctr   r9
-       mfxer   r10
-       mfcr    r11
-
-       /* Get the _mcount() call site out of LR */
-       mflr    r7
-       /* Save it as pt_regs->nip */
-       std     r7, _NIP(r1)
-       /* Save the read LR in pt_regs->link */
-       std     r0, _LINK(r1)
-
-       /* Save callee's TOC in the ABI compliant location */
-       std     r2, 24(r1)
-       ld      r2,PACATOC(r13) /* get kernel TOC in r2 */
-
-       addis   r3,r2,function_trace_op@toc@ha
-       addi    r3,r3,function_trace_op@toc@l
-       ld      r5,0(r3)
-
-#ifdef CONFIG_LIVEPATCH
-       mr      r14,r7          /* remember old NIP */
-#endif
-       /* Calculate ip from nip-4 into r3 for call below */
-       subi    r3, r7, MCOUNT_INSN_SIZE
-
-       /* Put the original return address in r4 as parent_ip */
-       mr      r4, r0
-
-       /* Save special regs */
-       std     r8, _MSR(r1)
-       std     r9, _CTR(r1)
-       std     r10, _XER(r1)
-       std     r11, _CCR(r1)
-
-       /* Load &pt_regs in r6 for call below */
-       addi    r6, r1 ,STACK_FRAME_OVERHEAD
-
-       /* ftrace_call(r3, r4, r5, r6) */
-.globl ftrace_call
-ftrace_call:
-       bl      ftrace_stub
-       nop
-
-       /* Load ctr with the possibly modified NIP */
-       ld      r3, _NIP(r1)
-       mtctr   r3
-#ifdef CONFIG_LIVEPATCH
-       cmpd    r14,r3          /* has NIP been altered? */
-#endif
-
-       /* Restore gprs */
-       REST_8GPRS(0,r1)
-       REST_8GPRS(8,r1)
-       REST_8GPRS(16,r1)
-       REST_8GPRS(24,r1)
-
-       /* Restore possibly modified LR */
-       ld      r0, _LINK(r1)
-       mtlr    r0
-
-       /* Restore callee's TOC */
-       ld      r2, 24(r1)
-
-       /* Pop our stack frame */
-       addi r1, r1, SWITCH_FRAME_SIZE
-
-#ifdef CONFIG_LIVEPATCH
-        /* Based on the cmpd above, if the NIP was altered handle livepatch */
-       bne-    livepatch_handler
-#endif
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-.globl ftrace_graph_call
-ftrace_graph_call:
-       b       ftrace_graph_stub
-_GLOBAL(ftrace_graph_stub)
-#endif
-
-       bctr                    /* jump after _mcount site */
-#endif /* CC_USING_MPROFILE_KERNEL */
-
-_GLOBAL(ftrace_stub)
-       blr
-
-#ifdef CONFIG_LIVEPATCH
-       /*
-        * This function runs in the mcount context, between two functions. As
-        * such it can only clobber registers which are volatile and used in
-        * function linkage.
-        *
-        * We get here when a function A, calls another function B, but B has
-        * been live patched with a new function C.
-        *
-        * On entry:
-        *  - we have no stack frame and can not allocate one
-        *  - LR points back to the original caller (in A)
-        *  - CTR holds the new NIP in C
-        *  - r0 & r12 are free
-        *
-        * r0 can't be used as the base register for a DS-form load or store, so
-        * we temporarily shuffle r1 (stack pointer) into r0 and then put it 
back.
-        */
-livepatch_handler:
-       CURRENT_THREAD_INFO(r12, r1)
-
-       /* Save stack pointer into r0 */
-       mr      r0, r1
-
-       /* Allocate 3 x 8 bytes */
-       ld      r1, TI_livepatch_sp(r12)
-       addi    r1, r1, 24
-       std     r1, TI_livepatch_sp(r12)
-
-       /* Save toc & real LR on livepatch stack */
-       std     r2,  -24(r1)
-       mflr    r12
-       std     r12, -16(r1)
-
-       /* Store stack end marker */
-       lis     r12, STACK_END_MAGIC@h
-       ori     r12, r12, STACK_END_MAGIC@l
-       std     r12, -8(r1)
-
-       /* Restore real stack pointer */
-       mr      r1, r0
-
-       /* Put ctr in r12 for global entry and branch there */
-       mfctr   r12
-       bctrl
-
-       /*
-        * Now we are returning from the patched function to the original
-        * caller A. We are free to use r0 and r12, and we can use r2 until we
-        * restore it.
-        */
-
-       CURRENT_THREAD_INFO(r12, r1)
-
-       /* Save stack pointer into r0 */
-       mr      r0, r1
-
-       ld      r1, TI_livepatch_sp(r12)
-
-       /* Check stack marker hasn't been trashed */
-       lis     r2,  STACK_END_MAGIC@h
-       ori     r2,  r2, STACK_END_MAGIC@l
-       ld      r12, -8(r1)
-1:     tdne    r12, r2
-       EMIT_BUG_ENTRY 1b, __FILE__, __LINE__ - 1, 0
-
-       /* Restore LR & toc from livepatch stack */
-       ld      r12, -16(r1)
-       mtlr    r12
-       ld      r2,  -24(r1)
-
-       /* Pop livepatch stack frame */
-       CURRENT_THREAD_INFO(r12, r0)
-       subi    r1, r1, 24
-       std     r1, TI_livepatch_sp(r12)
-
-       /* Restore real stack pointer */
-       mr      r1, r0
-
-       /* Return to original caller of live patched function */
-       blr
-#endif
-
-
-#else
-_GLOBAL_TOC(_mcount)
-EXPORT_SYMBOL(_mcount)
-       /* Taken from output of objdump from lib64/glibc */
-       mflr    r3
-       ld      r11, 0(r1)
-       stdu    r1, -112(r1)
-       std     r3, 128(r1)
-       ld      r4, 16(r11)
-
-       subi    r3, r3, MCOUNT_INSN_SIZE
-       LOAD_REG_ADDR(r5,ftrace_trace_function)
-       ld      r5,0(r5)
-       ld      r5,0(r5)
-       mtctr   r5
-       bctrl
-       nop
-
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-       b       ftrace_graph_caller
-#endif
-       ld      r0, 128(r1)
-       mtlr    r0
-       addi    r1, r1, 112
-_GLOBAL(ftrace_stub)
-       blr
-
-#endif /* CONFIG_DYNAMIC_FTRACE */
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-#ifndef CC_USING_MPROFILE_KERNEL
-_GLOBAL(ftrace_graph_caller)
-       /* load r4 with local address */
-       ld      r4, 128(r1)
-       subi    r4, r4, MCOUNT_INSN_SIZE
-
-       /* Grab the LR out of the caller stack frame */
-       ld      r11, 112(r1)
-       ld      r3, 16(r11)
-
-       bl      prepare_ftrace_return
-       nop
-
-       /*
-        * prepare_ftrace_return gives us the address we divert to.
-        * Change the LR in the callers stack frame to this.
-        */
-       ld      r11, 112(r1)
-       std     r3, 16(r11)
-
-       ld      r0, 128(r1)
-       mtlr    r0
-       addi    r1, r1, 112
-       blr
-
-#else /* CC_USING_MPROFILE_KERNEL */
-_GLOBAL(ftrace_graph_caller)
-       stdu    r1, -112(r1)
-       /* with -mprofile-kernel, parameter regs are still alive at _mcount */
-       std     r10, 104(r1)
-       std     r9, 96(r1)
-       std     r8, 88(r1)
-       std     r7, 80(r1)
-       std     r6, 72(r1)
-       std     r5, 64(r1)
-       std     r4, 56(r1)
-       std     r3, 48(r1)
-
-       /* Save callee's TOC in the ABI compliant location */
-       std     r2, 24(r1)
-       ld      r2, PACATOC(r13)        /* get kernel TOC in r2 */
-
-       mfctr   r4              /* ftrace_caller has moved local addr here */
-       std     r4, 40(r1)
-       mflr    r3              /* ftrace_caller has restored LR from stack */
-       subi    r4, r4, MCOUNT_INSN_SIZE
-
-       bl      prepare_ftrace_return
-       nop
-
-       /*
-        * prepare_ftrace_return gives us the address we divert to.
-        * Change the LR to this.
-        */
-       mtlr    r3
-
-       ld      r0, 40(r1)
-       mtctr   r0
-       ld      r10, 104(r1)
-       ld      r9, 96(r1)
-       ld      r8, 88(r1)
-       ld      r7, 80(r1)
-       ld      r6, 72(r1)
-       ld      r5, 64(r1)
-       ld      r4, 56(r1)
-       ld      r3, 48(r1)
-
-       /* Restore callee's TOC */
-       ld      r2, 24(r1)
-
-       addi    r1, r1, 112
-       mflr    r0
-       std     r0, LRSAVE(r1)
-       bctr
-#endif /* CC_USING_MPROFILE_KERNEL */
-
-_GLOBAL(return_to_handler)
-       /* need to save return values */
-       std     r4,  -32(r1)
-       std     r3,  -24(r1)
-       /* save TOC */
-       std     r2,  -16(r1)
-       std     r31, -8(r1)
-       mr      r31, r1
-       stdu    r1, -112(r1)
-
-       /*
-        * We might be called from a module.
-        * Switch to our TOC to run inside the core kernel.
-        */
-       ld      r2, PACATOC(r13)
-
-       bl      ftrace_return_to_handler
-       nop
-
-       /* return value has real return address */
-       mtlr    r3
-
-       ld      r1, 0(r1)
-       ld      r4,  -32(r1)
-       ld      r3,  -24(r1)
-       ld      r2,  -16(r1)
-       ld      r31, -8(r1)
-
-       /* Jump back to real return address */
-       blr
-#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-#endif /* CONFIG_FUNCTION_TRACER */
diff --git a/arch/powerpc/kernel/trace/Makefile 
b/arch/powerpc/kernel/trace/Makefile
new file mode 100644
index 000000000000..5f5a35254a9b
--- /dev/null
+++ b/arch/powerpc/kernel/trace/Makefile
@@ -0,0 +1,24 @@
+#
+# Makefile for the powerpc trace subsystem
+#
+
+subdir-ccflags-$(CONFIG_PPC_WERROR)    := -Werror
+
+ifdef CONFIG_FUNCTION_TRACER
+# do not trace tracer code
+CFLAGS_REMOVE_ftrace.o = -mno-sched-epilog $(CC_FLAGS_FTRACE)
+endif
+
+obj32-$(CONFIG_FUNCTION_TRACER)                += ftrace_32.o
+obj64-$(CONFIG_FUNCTION_TRACER)                += ftrace_64.o
+obj-$(CONFIG_DYNAMIC_FTRACE)           += ftrace.o
+obj-$(CONFIG_FUNCTION_GRAPH_TRACER)    += ftrace.o
+obj-$(CONFIG_FTRACE_SYSCALLS)          += ftrace.o
+obj-$(CONFIG_TRACING)                  += trace_clock.o
+
+obj-$(CONFIG_PPC64)                    += $(obj64-y)
+obj-$(CONFIG_PPC32)                    += $(obj32-y)
+
+# Disable GCOV & sanitizers in odd or sensitive code
+GCOV_PROFILE_ftrace.o := n
+UBSAN_SANITIZE_ftrace.o := n
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c
similarity index 100%
rename from arch/powerpc/kernel/ftrace.c
rename to arch/powerpc/kernel/trace/ftrace.c
diff --git a/arch/powerpc/kernel/trace/ftrace_32.S 
b/arch/powerpc/kernel/trace/ftrace_32.S
new file mode 100644
index 000000000000..afef2c076282
--- /dev/null
+++ b/arch/powerpc/kernel/trace/ftrace_32.S
@@ -0,0 +1,118 @@
+/*
+ * Split from entry_32.S
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/magic.h>
+#include <asm/reg.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/ftrace.h>
+#include <asm/export.h>
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+_GLOBAL(mcount)
+_GLOBAL(_mcount)
+       /*
+        * It is required that _mcount on PPC32 must preserve the
+        * link register. But we have r0 to play with. We use r0
+        * to push the return address back to the caller of mcount
+        * into the ctr register, restore the link register and
+        * then jump back using the ctr register.
+        */
+       mflr    r0
+       mtctr   r0
+       lwz     r0, 4(r1)
+       mtlr    r0
+       bctr
+
+_GLOBAL(ftrace_caller)
+       MCOUNT_SAVE_FRAME
+       /* r3 ends up with link register */
+       subi    r3, r3, MCOUNT_INSN_SIZE
+.globl ftrace_call
+ftrace_call:
+       bl      ftrace_stub
+       nop
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+.globl ftrace_graph_call
+ftrace_graph_call:
+       b       ftrace_graph_stub
+_GLOBAL(ftrace_graph_stub)
+#endif
+       MCOUNT_RESTORE_FRAME
+       /* old link register ends up in ctr reg */
+       bctr
+#else
+_GLOBAL(mcount)
+_GLOBAL(_mcount)
+
+       MCOUNT_SAVE_FRAME
+
+       subi    r3, r3, MCOUNT_INSN_SIZE
+       LOAD_REG_ADDR(r5, ftrace_trace_function)
+       lwz     r5,0(r5)
+
+       mtctr   r5
+       bctrl
+       nop
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+       b       ftrace_graph_caller
+#endif
+       MCOUNT_RESTORE_FRAME
+       bctr
+#endif
+EXPORT_SYMBOL(_mcount)
+
+_GLOBAL(ftrace_stub)
+       blr
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+_GLOBAL(ftrace_graph_caller)
+       /* load r4 with local address */
+       lwz     r4, 44(r1)
+       subi    r4, r4, MCOUNT_INSN_SIZE
+
+       /* Grab the LR out of the caller stack frame */
+       lwz     r3,52(r1)
+
+       bl      prepare_ftrace_return
+       nop
+
+        /*
+         * prepare_ftrace_return gives us the address we divert to.
+         * Change the LR in the callers stack frame to this.
+         */
+       stw     r3,52(r1)
+
+       MCOUNT_RESTORE_FRAME
+       /* old link register ends up in ctr reg */
+       bctr
+
+_GLOBAL(return_to_handler)
+       /* need to save return values */
+       stwu    r1, -32(r1)
+       stw     r3, 20(r1)
+       stw     r4, 16(r1)
+       stw     r31, 12(r1)
+       mr      r31, r1
+
+       bl      ftrace_return_to_handler
+       nop
+
+       /* return value has real return address */
+       mtlr    r3
+
+       lwz     r3, 20(r1)
+       lwz     r4, 16(r1)
+       lwz     r31,12(r1)
+       lwz     r1, 0(r1)
+
+       /* Jump back to real return address */
+       blr
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
diff --git a/arch/powerpc/kernel/trace/ftrace_64.S 
b/arch/powerpc/kernel/trace/ftrace_64.S
new file mode 100644
index 000000000000..587e7b5c0aff
--- /dev/null
+++ b/arch/powerpc/kernel/trace/ftrace_64.S
@@ -0,0 +1,389 @@
+/*
+ * Split from entry_64.S
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/magic.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/ftrace.h>
+#include <asm/ppc-opcode.h>
+#include <asm/export.h>
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+_GLOBAL(mcount)
+_GLOBAL(_mcount)
+EXPORT_SYMBOL(_mcount)
+       mflr    r12
+       mtctr   r12
+       mtlr    r0
+       bctr
+
+#ifndef CC_USING_MPROFILE_KERNEL
+_GLOBAL_TOC(ftrace_caller)
+       /* Taken from output of objdump from lib64/glibc */
+       mflr    r3
+       ld      r11, 0(r1)
+       stdu    r1, -112(r1)
+       std     r3, 128(r1)
+       ld      r4, 16(r11)
+       subi    r3, r3, MCOUNT_INSN_SIZE
+.globl ftrace_call
+ftrace_call:
+       bl      ftrace_stub
+       nop
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+.globl ftrace_graph_call
+ftrace_graph_call:
+       b       ftrace_graph_stub
+_GLOBAL(ftrace_graph_stub)
+#endif
+       ld      r0, 128(r1)
+       mtlr    r0
+       addi    r1, r1, 112
+
+#else /* CC_USING_MPROFILE_KERNEL */
+/*
+ *
+ * ftrace_caller() is the function that replaces _mcount() when ftrace is
+ * active.
+ *
+ * We arrive here after a function A calls function B, and we are the trace
+ * function for B. When we enter r1 points to A's stack frame, B has not yet
+ * had a chance to allocate one yet.
+ *
+ * Additionally r2 may point either to the TOC for A, or B, depending on
+ * whether B did a TOC setup sequence before calling us.
+ *
+ * On entry the LR points back to the _mcount() call site, and r0 holds the
+ * saved LR as it was on entry to B, ie. the original return address at the
+ * call site in A.
+ *
+ * Our job is to save the register state into a struct pt_regs (on the stack)
+ * and then arrange for the ftrace function to be called.
+ */
+_GLOBAL(ftrace_caller)
+       /* Save the original return address in A's stack frame */
+       std     r0,LRSAVE(r1)
+
+       /* Create our stack frame + pt_regs */
+       stdu    r1,-SWITCH_FRAME_SIZE(r1)
+
+       /* Save all gprs to pt_regs */
+       SAVE_8GPRS(0,r1)
+       SAVE_8GPRS(8,r1)
+       SAVE_8GPRS(16,r1)
+       SAVE_8GPRS(24,r1)
+
+       /* Load special regs for save below */
+       mfmsr   r8
+       mfctr   r9
+       mfxer   r10
+       mfcr    r11
+
+       /* Get the _mcount() call site out of LR */
+       mflr    r7
+       /* Save it as pt_regs->nip */
+       std     r7, _NIP(r1)
+       /* Save the read LR in pt_regs->link */
+       std     r0, _LINK(r1)
+
+       /* Save callee's TOC in the ABI compliant location */
+       std     r2, 24(r1)
+       ld      r2,PACATOC(r13) /* get kernel TOC in r2 */
+
+       addis   r3,r2,function_trace_op@toc@ha
+       addi    r3,r3,function_trace_op@toc@l
+       ld      r5,0(r3)
+
+#ifdef CONFIG_LIVEPATCH
+       mr      r14,r7          /* remember old NIP */
+#endif
+       /* Calculate ip from nip-4 into r3 for call below */
+       subi    r3, r7, MCOUNT_INSN_SIZE
+
+       /* Put the original return address in r4 as parent_ip */
+       mr      r4, r0
+
+       /* Save special regs */
+       std     r8, _MSR(r1)
+       std     r9, _CTR(r1)
+       std     r10, _XER(r1)
+       std     r11, _CCR(r1)
+
+       /* Load &pt_regs in r6 for call below */
+       addi    r6, r1 ,STACK_FRAME_OVERHEAD
+
+       /* ftrace_call(r3, r4, r5, r6) */
+.globl ftrace_call
+ftrace_call:
+       bl      ftrace_stub
+       nop
+
+       /* Load ctr with the possibly modified NIP */
+       ld      r3, _NIP(r1)
+       mtctr   r3
+#ifdef CONFIG_LIVEPATCH
+       cmpd    r14,r3          /* has NIP been altered? */
+#endif
+
+       /* Restore gprs */
+       REST_8GPRS(0,r1)
+       REST_8GPRS(8,r1)
+       REST_8GPRS(16,r1)
+       REST_8GPRS(24,r1)
+
+       /* Restore possibly modified LR */
+       ld      r0, _LINK(r1)
+       mtlr    r0
+
+       /* Restore callee's TOC */
+       ld      r2, 24(r1)
+
+       /* Pop our stack frame */
+       addi r1, r1, SWITCH_FRAME_SIZE
+
+#ifdef CONFIG_LIVEPATCH
+        /* Based on the cmpd above, if the NIP was altered handle livepatch */
+       bne-    livepatch_handler
+#endif
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+.globl ftrace_graph_call
+ftrace_graph_call:
+       b       ftrace_graph_stub
+_GLOBAL(ftrace_graph_stub)
+#endif
+
+       bctr                    /* jump after _mcount site */
+#endif /* CC_USING_MPROFILE_KERNEL */
+
+_GLOBAL(ftrace_stub)
+       blr
+
+#ifdef CONFIG_LIVEPATCH
+       /*
+        * This function runs in the mcount context, between two functions. As
+        * such it can only clobber registers which are volatile and used in
+        * function linkage.
+        *
+        * We get here when a function A, calls another function B, but B has
+        * been live patched with a new function C.
+        *
+        * On entry:
+        *  - we have no stack frame and can not allocate one
+        *  - LR points back to the original caller (in A)
+        *  - CTR holds the new NIP in C
+        *  - r0 & r12 are free
+        *
+        * r0 can't be used as the base register for a DS-form load or store, so
+        * we temporarily shuffle r1 (stack pointer) into r0 and then put it 
back.
+        */
+livepatch_handler:
+       CURRENT_THREAD_INFO(r12, r1)
+
+       /* Save stack pointer into r0 */
+       mr      r0, r1
+
+       /* Allocate 3 x 8 bytes */
+       ld      r1, TI_livepatch_sp(r12)
+       addi    r1, r1, 24
+       std     r1, TI_livepatch_sp(r12)
+
+       /* Save toc & real LR on livepatch stack */
+       std     r2,  -24(r1)
+       mflr    r12
+       std     r12, -16(r1)
+
+       /* Store stack end marker */
+       lis     r12, STACK_END_MAGIC@h
+       ori     r12, r12, STACK_END_MAGIC@l
+       std     r12, -8(r1)
+
+       /* Restore real stack pointer */
+       mr      r1, r0
+
+       /* Put ctr in r12 for global entry and branch there */
+       mfctr   r12
+       bctrl
+
+       /*
+        * Now we are returning from the patched function to the original
+        * caller A. We are free to use r0 and r12, and we can use r2 until we
+        * restore it.
+        */
+
+       CURRENT_THREAD_INFO(r12, r1)
+
+       /* Save stack pointer into r0 */
+       mr      r0, r1
+
+       ld      r1, TI_livepatch_sp(r12)
+
+       /* Check stack marker hasn't been trashed */
+       lis     r2,  STACK_END_MAGIC@h
+       ori     r2,  r2, STACK_END_MAGIC@l
+       ld      r12, -8(r1)
+1:     tdne    r12, r2
+       EMIT_BUG_ENTRY 1b, __FILE__, __LINE__ - 1, 0
+
+       /* Restore LR & toc from livepatch stack */
+       ld      r12, -16(r1)
+       mtlr    r12
+       ld      r2,  -24(r1)
+
+       /* Pop livepatch stack frame */
+       CURRENT_THREAD_INFO(r12, r0)
+       subi    r1, r1, 24
+       std     r1, TI_livepatch_sp(r12)
+
+       /* Restore real stack pointer */
+       mr      r1, r0
+
+       /* Return to original caller of live patched function */
+       blr
+#endif
+
+
+#else
+_GLOBAL_TOC(_mcount)
+EXPORT_SYMBOL(_mcount)
+       /* Taken from output of objdump from lib64/glibc */
+       mflr    r3
+       ld      r11, 0(r1)
+       stdu    r1, -112(r1)
+       std     r3, 128(r1)
+       ld      r4, 16(r11)
+
+       subi    r3, r3, MCOUNT_INSN_SIZE
+       LOAD_REG_ADDR(r5,ftrace_trace_function)
+       ld      r5,0(r5)
+       ld      r5,0(r5)
+       mtctr   r5
+       bctrl
+       nop
+
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+       b       ftrace_graph_caller
+#endif
+       ld      r0, 128(r1)
+       mtlr    r0
+       addi    r1, r1, 112
+_GLOBAL(ftrace_stub)
+       blr
+
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+#ifndef CC_USING_MPROFILE_KERNEL
+_GLOBAL(ftrace_graph_caller)
+       /* load r4 with local address */
+       ld      r4, 128(r1)
+       subi    r4, r4, MCOUNT_INSN_SIZE
+
+       /* Grab the LR out of the caller stack frame */
+       ld      r11, 112(r1)
+       ld      r3, 16(r11)
+
+       bl      prepare_ftrace_return
+       nop
+
+       /*
+        * prepare_ftrace_return gives us the address we divert to.
+        * Change the LR in the callers stack frame to this.
+        */
+       ld      r11, 112(r1)
+       std     r3, 16(r11)
+
+       ld      r0, 128(r1)
+       mtlr    r0
+       addi    r1, r1, 112
+       blr
+
+#else /* CC_USING_MPROFILE_KERNEL */
+_GLOBAL(ftrace_graph_caller)
+       stdu    r1, -112(r1)
+       /* with -mprofile-kernel, parameter regs are still alive at _mcount */
+       std     r10, 104(r1)
+       std     r9, 96(r1)
+       std     r8, 88(r1)
+       std     r7, 80(r1)
+       std     r6, 72(r1)
+       std     r5, 64(r1)
+       std     r4, 56(r1)
+       std     r3, 48(r1)
+
+       /* Save callee's TOC in the ABI compliant location */
+       std     r2, 24(r1)
+       ld      r2, PACATOC(r13)        /* get kernel TOC in r2 */
+
+       mfctr   r4              /* ftrace_caller has moved local addr here */
+       std     r4, 40(r1)
+       mflr    r3              /* ftrace_caller has restored LR from stack */
+       subi    r4, r4, MCOUNT_INSN_SIZE
+
+       bl      prepare_ftrace_return
+       nop
+
+       /*
+        * prepare_ftrace_return gives us the address we divert to.
+        * Change the LR to this.
+        */
+       mtlr    r3
+
+       ld      r0, 40(r1)
+       mtctr   r0
+       ld      r10, 104(r1)
+       ld      r9, 96(r1)
+       ld      r8, 88(r1)
+       ld      r7, 80(r1)
+       ld      r6, 72(r1)
+       ld      r5, 64(r1)
+       ld      r4, 56(r1)
+       ld      r3, 48(r1)
+
+       /* Restore callee's TOC */
+       ld      r2, 24(r1)
+
+       addi    r1, r1, 112
+       mflr    r0
+       std     r0, LRSAVE(r1)
+       bctr
+#endif /* CC_USING_MPROFILE_KERNEL */
+
+_GLOBAL(return_to_handler)
+       /* need to save return values */
+       std     r4,  -32(r1)
+       std     r3,  -24(r1)
+       /* save TOC */
+       std     r2,  -16(r1)
+       std     r31, -8(r1)
+       mr      r31, r1
+       stdu    r1, -112(r1)
+
+       /*
+        * We might be called from a module.
+        * Switch to our TOC to run inside the core kernel.
+        */
+       ld      r2, PACATOC(r13)
+
+       bl      ftrace_return_to_handler
+       nop
+
+       /* return value has real return address */
+       mtlr    r3
+
+       ld      r1, 0(r1)
+       ld      r4,  -32(r1)
+       ld      r3,  -24(r1)
+       ld      r2,  -16(r1)
+       ld      r31, -8(r1)
+
+       /* Jump back to real return address */
+       blr
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
diff --git a/arch/powerpc/kernel/trace_clock.c 
b/arch/powerpc/kernel/trace/trace_clock.c
similarity index 100%
rename from arch/powerpc/kernel/trace_clock.c
rename to arch/powerpc/kernel/trace/trace_clock.c
-- 
2.12.1

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