Commit 1fa9d67a authored by Steven Rostedt (VMware)'s avatar Steven Rostedt (VMware) Committed by Thomas Gleixner
Browse files

x86/ftrace: Use Makefile logic instead of #ifdef for compiling ftrace_*.o 



Currently ftrace_32.S and ftrace_64.S are compiled even when
CONFIG_FUNCTION_TRACER is not set. This means there's an unnecessary #ifdef
to protect the code. Instead of using preprocessor directives, only compile
those files when FUNCTION_TRACER is defined.

Suggested-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: default avatarIngo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20170316210043.peycxdxktwwn6cid@treble
Link: http://lkml.kernel.org/r/20170323143446.217684991@goodmis.org


Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 644e0e8d

arch/x86/kernel/Makefile

+2 −2
Original line number Diff line number Diff line
@@ -46,8 +46,7 @@ obj-$(CONFIG_MODIFY_LDT_SYSCALL) += ldt.o 
obj-y			+= setup.o x86_init.o i8259.o irqinit.o jump_label.o

obj-$(CONFIG_IRQ_WORK)  += irq_work.o

obj-y			+= probe_roms.o

obj-$(CONFIG_X86_64)	+= sys_x86_64.o ftrace_64.o

obj-$(CONFIG_X86_32)	+= ftrace_32.o

obj-$(CONFIG_X86_64)	+= sys_x86_64.o

obj-$(CONFIG_X86_ESPFIX64)	+= espfix_64.o

obj-$(CONFIG_SYSFS)	+= ksysfs.o

obj-y			+= bootflag.o e820.o
@@ -83,6 +82,7 @@ obj-y += apic/ 
obj-$(CONFIG_X86_REBOOTFIXUPS)	+= reboot_fixups_32.o

obj-$(CONFIG_DYNAMIC_FTRACE)	+= ftrace.o

obj-$(CONFIG_LIVEPATCH)	+= livepatch.o

obj-$(CONFIG_FUNCTION_TRACER)	+= ftrace_$(BITS).o

obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o

obj-$(CONFIG_FTRACE_SYSCALLS)	+= ftrace.o

obj-$(CONFIG_X86_TSC)		+= trace_clock.o

arch/x86/kernel/ftrace_32.S

+0 −3
Original line number Diff line number Diff line
@@ -8,8 +8,6 @@ 
#include <asm/export.h>

#include <asm/ftrace.h>



#ifdef CONFIG_FUNCTION_TRACER



#ifdef CC_USING_FENTRY

# define function_hook	__fentry__

EXPORT_SYMBOL(__fentry__)
@@ -206,7 +204,6 @@ ftrace_stub: 
	jmp	ftrace_stub

END(function_hook)

#endif /* CONFIG_DYNAMIC_FTRACE */

#endif /* CONFIG_FUNCTION_TRACER */



#ifdef CONFIG_FUNCTION_GRAPH_TRACER

ENTRY(ftrace_graph_caller)

arch/x86/kernel/ftrace_64.S

+0 −4
Original line number Diff line number Diff line
@@ -11,9 +11,6 @@ 
	.code64

	.section .entry.text, "ax"





#ifdef CONFIG_FUNCTION_TRACER



#ifdef CC_USING_FENTRY

# define function_hook	__fentry__

EXPORT_SYMBOL(__fentry__)
@@ -295,7 +292,6 @@ trace: 
	jmp fgraph_trace

END(function_hook)

#endif /* CONFIG_DYNAMIC_FTRACE */

#endif /* CONFIG_FUNCTION_TRACER */



#ifdef CONFIG_FUNCTION_GRAPH_TRACER

ENTRY(ftrace_graph_caller)

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