s390/ftrace: Add -mfentry and -mnop-mcount support

Utilize -mfentry and -mnop-mcount gcc options together with
-mrecord-mcount to get compiler generated calls to the profiling functions
as nops which are compatible with current -mhotpatch=0,3 approach.  At the
same time -mrecord-mcount enables __mcount_loc section generation by
the compiler which allows to avoid using scripts/recordmcount.pl script.

Link: http://lkml.kernel.org/r/patch-4.thread-aa7b8d.git-aa7b8dbf236f.your-ad-here.call-01533557518-ext-9465@work.hours

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Vasily Gorbik 2018-08-06 15:17:47 +02:00 committed by Steven Rostedt (VMware)
parent 2f4df0017b
commit d983c89cc9
5 changed files with 16 additions and 12 deletions

View File

@ -136,6 +136,7 @@ config S390
select HAVE_DYNAMIC_FTRACE
select HAVE_DYNAMIC_FTRACE_WITH_REGS
select HAVE_EFFICIENT_UNALIGNED_ACCESS
select HAVE_FENTRY
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_FUNCTION_GRAPH_TRACER
select HAVE_FUNCTION_TRACER
@ -157,6 +158,7 @@ config S390
select HAVE_MEMBLOCK_NODE_MAP
select HAVE_MEMBLOCK_PHYS_MAP
select HAVE_MOD_ARCH_SPECIFIC
select HAVE_NOP_MCOUNT
select HAVE_OPROFILE
select HAVE_PERF_EVENTS
select HAVE_REGS_AND_STACK_ACCESS_API

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@ -86,13 +86,15 @@ ifdef CONFIG_EXPOLINE
endif
ifdef CONFIG_FUNCTION_TRACER
# make use of hotpatch feature if the compiler supports it
cc_hotpatch := -mhotpatch=0,3
ifeq ($(call cc-option-yn,$(cc_hotpatch)),y)
CC_FLAGS_FTRACE := $(cc_hotpatch)
KBUILD_AFLAGS += -DCC_USING_HOTPATCH
KBUILD_CFLAGS += -DCC_USING_HOTPATCH
endif
ifeq ($(call cc-option-yn,-mfentry -mnop-mcount),n)
# make use of hotpatch feature if the compiler supports it
cc_hotpatch := -mhotpatch=0,3
ifeq ($(call cc-option-yn,$(cc_hotpatch)),y)
CC_FLAGS_FTRACE := $(cc_hotpatch)
KBUILD_AFLAGS += -DCC_USING_HOTPATCH
KBUILD_CFLAGS += -DCC_USING_HOTPATCH
endif
endif
endif
# Test CFI features of binutils

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@ -4,7 +4,7 @@
#define ARCH_SUPPORTS_FTRACE_OPS 1
#ifdef CC_USING_HOTPATCH
#if defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT)
#define MCOUNT_INSN_SIZE 6
#else
#define MCOUNT_INSN_SIZE 24
@ -42,7 +42,7 @@ struct ftrace_insn {
static inline void ftrace_generate_nop_insn(struct ftrace_insn *insn)
{
#ifdef CONFIG_FUNCTION_TRACER
#ifdef CC_USING_HOTPATCH
#if defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT)
/* brcl 0,0 */
insn->opc = 0xc004;
insn->disp = 0;
@ -57,7 +57,7 @@ static inline void ftrace_generate_nop_insn(struct ftrace_insn *insn)
static inline int is_ftrace_nop(struct ftrace_insn *insn)
{
#ifdef CONFIG_FUNCTION_TRACER
#ifdef CC_USING_HOTPATCH
#if defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT)
if (insn->disp == 0)
return 1;
#else

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@ -61,7 +61,7 @@ unsigned long ftrace_plt;
static inline void ftrace_generate_orig_insn(struct ftrace_insn *insn)
{
#ifdef CC_USING_HOTPATCH
#if defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT)
/* brcl 0,0 */
insn->opc = 0xc004;
insn->disp = 0;

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@ -35,7 +35,7 @@ ENTRY(ftrace_caller)
.globl ftrace_regs_caller
.set ftrace_regs_caller,ftrace_caller
lgr %r1,%r15
#ifndef CC_USING_HOTPATCH
#if !(defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT))
aghi %r0,MCOUNT_RETURN_FIXUP
#endif
aghi %r15,-STACK_FRAME_SIZE