Re: [PATCH -tip] x86: move vmware to hypervisor

[Jaswinder Singh Rajput <jaswinder@kernel.org>]

On Tue, 2009-03-17 at 08:50 -0700, H. Peter Anvin wrote:
> Jaswinder Singh Rajput wrote:
> >> I dont really like this one. KVM is a hypervisor too, and so is 
> >> Xen and lguest. VMware is one of the many types of a 
> >> hypervisors.
> > 
> > Can we use common hypervisor for Xen, lguest, vmware, etc.
> > And Xen, lguest, vmware will be the sub-options.
> 
> Obviously.  We spent a lot of time breaking up the cpu stuff into common
> and vendor-specific portions, we shouldn't go backwards w.r.t. hypervisors.
> 	

OK, agreed.

But atleast give freedom to users to disable this who are not willing to
use it.

Currently hypervisor is used only used by VMWARE, so is I prepare this
freedom patch:

From: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Date: Wed, 25 Mar 2009 10:40:01 +0530
Subject: [PATCH] x86: Introduce CONFIG_X86_VMWARE option

Impact: freedom to choose

Gives freedom to users to select or suppress CONFIG_X86_VMWARE option.

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
---
 arch/x86/Kconfig                  |    7 +++++++
 arch/x86/include/asm/hypervisor.h |    9 +++++++++
 arch/x86/kernel/cpu/Makefile      |    2 +-
 3 files changed, 17 insertions(+), 1 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index f5d7d29..56e1a9c 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -554,6 +554,13 @@ config HPET_EMULATE_RTC
 	def_bool y
 	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 
+config X86_VMWARE
+	bool
+	default n
+	prompt "X86 VMware support"
+	---help---
+	 Enable X86 VMware Hypervisor support.
+
 # Mark as embedded because too many people got it wrong.
 # The code disables itself when not needed.
 config DMI
diff --git a/arch/x86/include/asm/hypervisor.h b/arch/x86/include/asm/hypervisor.h
index 369f5c5..c08ae75 100644
--- a/arch/x86/include/asm/hypervisor.h
+++ b/arch/x86/include/asm/hypervisor.h
@@ -20,7 +20,16 @@
 #ifndef ASM_X86__HYPERVISOR_H
 #define ASM_X86__HYPERVISOR_H
 
+#ifdef CONFIG_X86_VMWARE
 extern unsigned long get_hypervisor_tsc_freq(void);
 extern void init_hypervisor(struct cpuinfo_x86 *c);
+#else
+static inline unsigned long get_hypervisor_tsc_freq(void)
+{
+	return 0;
+}
+
+static inline void init_hypervisor(struct cpuinfo_x86 *c) {}
+#endif
 
 #endif
diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile
index 3efcb2b..24372f7 100644
--- a/arch/x86/kernel/cpu/Makefile
+++ b/arch/x86/kernel/cpu/Makefile
@@ -9,11 +9,11 @@ endif
 
 obj-y			:= intel_cacheinfo.o addon_cpuid_features.o
 obj-y			+= proc.o capflags.o powerflags.o common.o
-obj-y			+= vmware.o hypervisor.o
 
 obj-$(CONFIG_X86_32)	+= bugs.o cmpxchg.o
 obj-$(CONFIG_X86_64)	+= bugs_64.o
 
+obj-$(CONFIG_X86_VMWARE)		+= vmware.o hypervisor.o
 obj-$(CONFIG_X86_CPU_DEBUG)		+= cpu_debug.o
 
 obj-$(CONFIG_CPU_SUP_INTEL)		+= intel.o
-- 
1.6.0.6