linux/arch/x86/include/asm/kvm_para.h
Linus Torvalds 816434ec4a Merge branch 'x86-spinlocks-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 spinlock changes from Ingo Molnar:
 "The biggest change here are paravirtualized ticket spinlocks (PV
  spinlocks), which bring a nice speedup on various benchmarks.

  The KVM host side will come to you via the KVM tree"

* 'x86-spinlocks-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/kvm/guest: Fix sparse warning: "symbol 'klock_waiting' was not declared as static"
  kvm: Paravirtual ticketlocks support for linux guests running on KVM hypervisor
  kvm guest: Add configuration support to enable debug information for KVM Guests
  kvm uapi: Add KICK_CPU and PV_UNHALT definition to uapi
  xen, pvticketlock: Allow interrupts to be enabled while blocking
  x86, ticketlock: Add slowpath logic
  jump_label: Split jumplabel ratelimit
  x86, pvticketlock: When paravirtualizing ticket locks, increment by 2
  x86, pvticketlock: Use callee-save for lock_spinning
  xen, pvticketlocks: Add xen_nopvspin parameter to disable xen pv ticketlocks
  xen, pvticketlock: Xen implementation for PV ticket locks
  xen: Defer spinlock setup until boot CPU setup
  x86, ticketlock: Collapse a layer of functions
  x86, ticketlock: Don't inline _spin_unlock when using paravirt spinlocks
  x86, spinlock: Replace pv spinlocks with pv ticketlocks
2013-09-04 11:55:10 -07:00

141 lines
3.3 KiB
C

#ifndef _ASM_X86_KVM_PARA_H
#define _ASM_X86_KVM_PARA_H
#include <asm/processor.h>
#include <uapi/asm/kvm_para.h>
extern void kvmclock_init(void);
extern int kvm_register_clock(char *txt);
#ifdef CONFIG_KVM_GUEST
bool kvm_check_and_clear_guest_paused(void);
#else
static inline bool kvm_check_and_clear_guest_paused(void)
{
return false;
}
#endif /* CONFIG_KVM_GUEST */
/* This instruction is vmcall. On non-VT architectures, it will generate a
* trap that we will then rewrite to the appropriate instruction.
*/
#define KVM_HYPERCALL ".byte 0x0f,0x01,0xc1"
/* For KVM hypercalls, a three-byte sequence of either the vmcall or the vmmcall
* instruction. The hypervisor may replace it with something else but only the
* instructions are guaranteed to be supported.
*
* Up to four arguments may be passed in rbx, rcx, rdx, and rsi respectively.
* The hypercall number should be placed in rax and the return value will be
* placed in rax. No other registers will be clobbered unless explicitly
* noted by the particular hypercall.
*/
static inline long kvm_hypercall0(unsigned int nr)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr)
: "memory");
return ret;
}
static inline long kvm_hypercall1(unsigned int nr, unsigned long p1)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1)
: "memory");
return ret;
}
static inline long kvm_hypercall2(unsigned int nr, unsigned long p1,
unsigned long p2)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2)
: "memory");
return ret;
}
static inline long kvm_hypercall3(unsigned int nr, unsigned long p1,
unsigned long p2, unsigned long p3)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2), "d"(p3)
: "memory");
return ret;
}
static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
unsigned long p2, unsigned long p3,
unsigned long p4)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4)
: "memory");
return ret;
}
static inline uint32_t kvm_cpuid_base(void)
{
if (boot_cpu_data.cpuid_level < 0)
return 0; /* So we don't blow up on old processors */
if (cpu_has_hypervisor)
return hypervisor_cpuid_base("KVMKVMKVM\0\0\0", 0);
return 0;
}
static inline bool kvm_para_available(void)
{
return kvm_cpuid_base() != 0;
}
static inline unsigned int kvm_arch_para_features(void)
{
return cpuid_eax(KVM_CPUID_FEATURES);
}
#ifdef CONFIG_KVM_GUEST
void __init kvm_guest_init(void);
void kvm_async_pf_task_wait(u32 token);
void kvm_async_pf_task_wake(u32 token);
u32 kvm_read_and_reset_pf_reason(void);
extern void kvm_disable_steal_time(void);
#ifdef CONFIG_PARAVIRT_SPINLOCKS
void __init kvm_spinlock_init(void);
#else /* !CONFIG_PARAVIRT_SPINLOCKS */
static inline void kvm_spinlock_init(void)
{
}
#endif /* CONFIG_PARAVIRT_SPINLOCKS */
#else /* CONFIG_KVM_GUEST */
#define kvm_guest_init() do {} while (0)
#define kvm_async_pf_task_wait(T) do {} while(0)
#define kvm_async_pf_task_wake(T) do {} while(0)
static inline u32 kvm_read_and_reset_pf_reason(void)
{
return 0;
}
static inline void kvm_disable_steal_time(void)
{
return;
}
#endif
#endif /* _ASM_X86_KVM_PARA_H */