[for-next][PATCH 17/32] ftrace: x86: Remove check of obsolete variable function_trace_stop

Steven Rostedt
2014-07-19T13:16:49Z

[-- Attachment #1: 0017-ftrace-x86-Remove-check-of-obsolete-variable-functio.patch --]
[-- Type: text/plain, Size: 3543 bytes --]

From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>

Nothing sets function_trace_stop to disable function tracing anymore.
Remove the check for it in the arch code.

Link: http://lkml.kernel.org/r/53C54D32.6000000@zytor.com

Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
arch/x86/Kconfig | 1 -
arch/x86/kernel/entry_32.S | 9 ---------
arch/x86/kernel/mcount_64.S | 18 +-----------------
3 files changed, 1 insertion(+), 27 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index a8f749ef0fdc..5b45e8fccaca 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -54,7 +54,6 @@ config X86
select HAVE_FUNCTION_TRACER
select HAVE_FUNCTION_GRAPH_TRACER
select HAVE_FUNCTION_GRAPH_FP_TEST
- select HAVE_FUNCTION_TRACE_MCOUNT_TEST
select HAVE_SYSCALL_TRACEPOINTS
select SYSCTL_EXCEPTION_TRACE
select HAVE_KVM
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index dbaa23e78b36..64762c62e8a7 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -1058,9 +1058,6 @@ ENTRY(mcount)
END(mcount)

ENTRY(ftrace_caller)
- cmpl $0, function_trace_stop
- jne ftrace_stub
-
pushl %eax
pushl %ecx
pushl %edx
@@ -1092,8 +1089,6 @@ END(ftrace_caller)

ENTRY(ftrace_regs_caller)
pushf /* push flags before compare (in cs location) */
- cmpl $0, function_trace_stop
- jne ftrace_restore_flags

/*
* i386 does not save SS and ESP when coming from kernel.
@@ -1152,7 +1147,6 @@ GLOBAL(ftrace_regs_call)
popf /* Pop flags at end (no addl to corrupt flags) */
jmp ftrace_ret

-ftrace_restore_flags:
popf
jmp ftrace_stub
#else /* ! CONFIG_DYNAMIC_FTRACE */
@@ -1161,9 +1155,6 @@ ENTRY(mcount)
cmpl $__PAGE_OFFSET, %esp
jb ftrace_stub /* Paging not enabled yet? */

- cmpl $0, function_trace_stop
- jne ftrace_stub
-
cmpl $ftrace_stub, ftrace_trace_function
jnz trace
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
diff --git a/arch/x86/kernel/mcount_64.S b/arch/x86/kernel/mcount_64.S
index 6b4e3c3b3d74..c73aecf10d34 100644
--- a/arch/x86/kernel/mcount_64.S
+++ b/arch/x86/kernel/mcount_64.S
@@ -46,10 +46,6 @@ END(function_hook)
.endm

ENTRY(ftrace_caller)
- /* Check if tracing was disabled (quick check) */
- cmpl $0, function_trace_stop
- jne ftrace_stub
-
ftrace_caller_setup
/* regs go into 4th parameter (but make it NULL) */
movq $0, %rcx
@@ -73,10 +69,6 @@ ENTRY(ftrace_regs_caller)
/* Save the current flags before compare (in SS location)*/
pushfq

- /* Check if tracing was disabled (quick check) */
- cmpl $0, function_trace_stop
- jne ftrace_restore_flags
-
/* skip=8 to skip flags saved in SS */
ftrace_caller_setup 8

@@ -131,7 +123,7 @@ GLOBAL(ftrace_regs_call)
popfq

jmp ftrace_return
-ftrace_restore_flags:
+
popfq
jmp ftrace_stub

@@ -141,9 +133,6 @@ END(ftrace_regs_caller)
#else /* ! CONFIG_DYNAMIC_FTRACE */

ENTRY(function_hook)
- cmpl $0, function_trace_stop
- jne ftrace_stub
-
cmpq $ftrace_stub, ftrace_trace_function
jnz trace

@@ -182,10 +171,6 @@ END(function_hook)
ENTRY(ftrace_graph_caller)
MCOUNT_SAVE_FRAME

- /* Check if tracing was disabled (quick check) */
- cmpl $0, function_trace_stop
- jne fgraph_skip
-
#ifdef CC_USING_FENTRY
leaq SS+16(%rsp), %rdi
movq $0, %rdx /* No framepointers needed */
@@ -198,7 +183,6 @@ ENTRY(ftrace_graph_caller)

call prepare_ftrace_return

-fgraph_skip:
MCOUNT_RESTORE_FRAME

retq
--
2.0.1