linux_dsm_epyc7002/arch/powerpc/kernel/trace/ftrace_64_pg.S
Michael Ellerman 0c0c52306f powerpc: Only support DYNAMIC_FTRACE not static
We've had dynamic ftrace support for over 9 years since Steve first
wrote it, all the distros use dynamic, and static is basically
untested these days, so drop support for static ftrace.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-03 22:32:29 +10:00

71 lines
1.4 KiB
ArmAsm

/*
* Split from ftrace_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>
_GLOBAL_TOC(ftrace_caller)
lbz r3, PACA_FTRACE_ENABLED(r13)
cmpdi r3, 0
beqlr
/* 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
_GLOBAL(ftrace_stub)
blr
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
_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
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */