linux/arch/s390/kernel/mcount.S
Heiko Carstens 5d6a016349 s390/ftrace: enforce DYNAMIC_FTRACE if FUNCTION_TRACER is selected
We have too many combinations for function tracing. Lets simply stick to
the most advanced option, so we don't have to care of other combinations.

This means we always select DYNAMIC_FTRACE if FUNCTION_TRACER is selected.

In the s390 Makefile also remove CONFIG_FTRACE_SYSCALLS since that
functionality got moved to architecture independent code in the meantime.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-09-09 08:53:29 +02:00

68 lines
1.2 KiB
ArmAsm

/*
* Copyright IBM Corp. 2008, 2009
*
* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
*
*/
#include <linux/linkage.h>
#include <asm/asm-offsets.h>
#include <asm/ftrace.h>
.section .kprobes.text, "ax"
ENTRY(ftrace_stub)
br %r14
ENTRY(_mcount)
br %r14
ENTRY(ftrace_caller)
stm %r2,%r5,16(%r15)
bras %r1,1f
0: .long ftrace_trace_function
1: st %r14,56(%r15)
lr %r0,%r15
ahi %r15,-96
l %r3,100(%r15)
la %r2,0(%r14)
st %r0,__SF_BACKCHAIN(%r15)
la %r3,0(%r3)
ahi %r2,-MCOUNT_INSN_SIZE
l %r14,0b-0b(%r1)
l %r14,0(%r14)
basr %r14,%r14
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
l %r2,100(%r15)
l %r3,152(%r15)
ENTRY(ftrace_graph_caller)
# The bras instruction gets runtime patched to call prepare_ftrace_return.
# See ftrace_enable_ftrace_graph_caller. The patched instruction is:
# bras %r14,prepare_ftrace_return
bras %r14,0f
0: st %r2,100(%r15)
#endif
ahi %r15,96
l %r14,56(%r15)
lm %r2,%r5,16(%r15)
br %r14
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
ENTRY(return_to_handler)
stm %r2,%r5,16(%r15)
st %r14,56(%r15)
lr %r0,%r15
ahi %r15,-96
st %r0,__SF_BACKCHAIN(%r15)
bras %r1,0f
.long ftrace_return_to_handler
0: l %r2,0b-0b(%r1)
basr %r14,%r2
lr %r14,%r2
ahi %r15,96
lm %r2,%r5,16(%r15)
br %r14
#endif