linux-kernel - [PATCH] x86: remove redundant 'default n' from Kconfig-s

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Date:   Tue, 16 Oct 2018 15:42:16 +0200
From:   Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>
To:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        "H. Peter Anvin" <hpa@...or.com>, x86@...nel.org
Cc:     Boris Ostrovsky <boris.ostrovsky@...cle.com>,
        Juergen Gross <jgross@...e.co>, xen-devel@...ts.xenproject.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH] x86: remove redundant 'default n' from Kconfig-s

'default n' is the default value for any bool or tristate Kconfig
setting so there is no need to write it explicitly.

Also since commit f467c5640c29 ("kconfig: only write '# CONFIG_FOO
is not set' for visible symbols") the Kconfig behavior is the same
regardless of 'default n' being present or not:

    ...
    One side effect of (and the main motivation for) this change is making
    the following two definitions behave exactly the same:
    
        config FOO
                bool
    
        config FOO
                bool
                default n
    
    With this change, neither of these will generate a
    '# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
    That might make it clearer to people that a bare 'default n' is
    redundant.
    ...

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>
---
 arch/x86/Kconfig       |    7 -------
 arch/x86/Kconfig.debug |    1 -
 arch/x86/xen/Kconfig   |    1 -
 3 files changed, 9 deletions(-)

Index: b/arch/x86/Kconfig
===================================================================
--- a/arch/x86/Kconfig	2018-10-09 15:58:36.747122883 +0200
+++ b/arch/x86/Kconfig	2018-10-16 15:37:16.787643127 +0200
@@ -449,7 +449,6 @@ config RETPOLINE
 
 config INTEL_RDT
 	bool "Intel Resource Director Technology support"
-	default n
 	depends on X86 && CPU_SUP_INTEL
 	select KERNFS
 	help
@@ -704,7 +703,6 @@ config STA2X11
 	select SWIOTLB
 	select MFD_STA2X11
 	select GPIOLIB
-	default n
 	---help---
 	  This adds support for boards based on the STA2X11 IO-Hub,
 	  a.k.a. "ConneXt". The chip is used in place of the standard
@@ -805,7 +803,6 @@ config KVM_GUEST
 config KVM_DEBUG_FS
 	bool "Enable debug information for KVM Guests in debugfs"
 	depends on KVM_GUEST && DEBUG_FS
-	default n
 	---help---
 	  This option enables collection of various statistics for KVM guest.
 	  Statistics are displayed in debugfs filesystem. Enabling this option
@@ -814,7 +811,6 @@ config KVM_DEBUG_FS
 config PARAVIRT_TIME_ACCOUNTING
 	bool "Paravirtual steal time accounting"
 	depends on PARAVIRT
-	default n
 	---help---
 	  Select this option to enable fine granularity task steal time
 	  accounting. Time spent executing other tasks in parallel with
@@ -1171,7 +1167,6 @@ source "arch/x86/events/Kconfig"
 
 config X86_LEGACY_VM86
 	bool "Legacy VM86 support"
-	default n
 	depends on X86_32
 	---help---
 	  This option allows user programs to put the CPU into V8086
@@ -2231,7 +2226,6 @@ config HOTPLUG_CPU
 
 config BOOTPARAM_HOTPLUG_CPU0
 	bool "Set default setting of cpu0_hotpluggable"
-	default n
 	depends on HOTPLUG_CPU
 	---help---
 	  Set whether default state of cpu0_hotpluggable is on or off.
@@ -2792,7 +2786,6 @@ source "drivers/pcmcia/Kconfig"
 config RAPIDIO
 	tristate "RapidIO support"
 	depends on PCI
-	default n
 	help
 	  If enabled this option will include drivers and the core
 	  infrastructure code to support RapidIO interconnect devices.
Index: b/arch/x86/Kconfig.debug
===================================================================
--- a/arch/x86/Kconfig.debug	2018-09-26 15:54:31.898819765 +0200
+++ b/arch/x86/Kconfig.debug	2018-10-16 15:37:37.903643659 +0200
@@ -314,7 +314,6 @@ config DEBUG_NMI_SELFTEST
 
 config DEBUG_IMR_SELFTEST
 	bool "Isolated Memory Region self test"
-	default n
 	depends on INTEL_IMR
 	---help---
 	  This option enables automated sanity testing of the IMR code.
Index: b/arch/x86/xen/Kconfig
===================================================================
--- a/arch/x86/xen/Kconfig	2018-10-09 15:58:37.003122889 +0200
+++ b/arch/x86/xen/Kconfig	2018-10-16 15:37:53.031644040 +0200
@@ -69,7 +69,6 @@ config XEN_SAVE_RESTORE
 config XEN_DEBUG_FS
 	bool "Enable Xen debug and tuning parameters in debugfs"
 	depends on XEN && DEBUG_FS
-	default n
 	help
 	  Enable statistics output and various tuning options in debugfs.
 	  Enabling this option may incur a significant performance overhead.