[S390] ftrace: add function trace mcount test support
Add support for early test if the function tracer is enabled or
disabled. Saves some extra function calls.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index b674e79..480590f 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -82,6 +82,7 @@
select USE_GENERIC_SMP_HELPERS if SMP
select HAVE_SYSCALL_WRAPPERS
select HAVE_FUNCTION_TRACER
+ select HAVE_FUNCTION_TRACE_MCOUNT_TEST
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_DYNAMIC_FTRACE
select HAVE_DEFAULT_NO_SPIN_MUTEXES
diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S
index de27499..0aa85ec 100644
--- a/arch/s390/kernel/mcount.S
+++ b/arch/s390/kernel/mcount.S
@@ -21,6 +21,9 @@
.globl ftrace_caller
ftrace_caller:
+ larl %r1,function_trace_stop
+ icm %r1,0xf,0(%r1)
+ bnzr %r14
stmg %r2,%r5,32(%r15)
stg %r14,112(%r15)
lgr %r1,%r15
@@ -46,6 +49,9 @@
.globl _mcount
_mcount:
+ larl %r1,function_trace_stop
+ icm %r1,0xf,0(%r1)
+ bnzr %r14
stmg %r2,%r5,32(%r15)
stg %r14,112(%r15)
lgr %r1,%r15
@@ -74,21 +80,25 @@
.globl ftrace_caller
ftrace_caller:
stm %r2,%r5,16(%r15)
+ bras %r1,2f
+0: .long ftrace_trace_function
+1: .long function_trace_stop
+2: l %r2,1b-0b(%r1)
+ icm %r2,0xf,0(%r2)
+ jnz 3f
st %r14,56(%r15)
- lr %r1,%r15
+ lr %r0,%r15
ahi %r15,-96
l %r3,100(%r15)
la %r2,0(%r14)
- st %r1,__SF_BACKCHAIN(%r15)
+ st %r0,__SF_BACKCHAIN(%r15)
la %r3,0(%r3)
- bras %r14,0f
- .long ftrace_dyn_func
-0: l %r14,0(%r14)
+ l %r14,0b-0b(%r1)
l %r14,0(%r14)
basr %r14,%r14
ahi %r15,96
- lm %r2,%r5,16(%r15)
l %r14,56(%r15)
+3: lm %r2,%r5,16(%r15)
br %r14
.data
@@ -102,21 +112,25 @@
.globl _mcount
_mcount:
stm %r2,%r5,16(%r15)
+ bras %r1,2f
+0: .long ftrace_trace_function
+1: .long function_trace_stop
+2: l %r2,1b-0b(%r1)
+ icm %r2,0xf,0(%r2)
+ jnz 3f
st %r14,56(%r15)
- lr %r1,%r15
+ lr %r0,%r15
ahi %r15,-96
l %r3,100(%r15)
la %r2,0(%r14)
- st %r1,__SF_BACKCHAIN(%r15)
+ st %r0,__SF_BACKCHAIN(%r15)
la %r3,0(%r3)
- bras %r14,0f
- .long ftrace_trace_function
-0: l %r14,0(%r14)
+ l %r14,0b-0b(%r1)
l %r14,0(%r14)
basr %r14,%r14
ahi %r15,96
- lm %r2,%r5,16(%r15)
l %r14,56(%r15)
+3: lm %r2,%r5,16(%r15)
br %r14
#endif /* CONFIG_DYNAMIC_FTRACE */