diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/include/asm/mwait.h | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/process.c | 51 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx.c | 7 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 10 | ||||
| -rw-r--r-- | arch/x86/mm/hugetlbpage.c | 12 |
5 files changed, 72 insertions, 16 deletions
diff --git a/arch/x86/include/asm/mwait.h b/arch/x86/include/asm/mwait.h index a1410db38a1a..653dfa7662e1 100644 --- a/arch/x86/include/asm/mwait.h +++ b/arch/x86/include/asm/mwait.h @@ -30,6 +30,14 @@ static inline void __mwait(unsigned long eax, unsigned long ecx) :: "a" (eax), "c" (ecx)); } +static inline void __sti_mwait(unsigned long eax, unsigned long ecx) +{ + trace_hardirqs_on(); + /* "mwait %eax, %ecx;" */ + asm volatile("sti; .byte 0x0f, 0x01, 0xc9;" + :: "a" (eax), "c" (ecx)); +} + /* * This uses new MONITOR/MWAIT instructions on P4 processors with PNI, * which can obviate IPI to trigger checking of need_resched. diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index e127ddaa2d5a..6ad8a6396b75 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -24,6 +24,7 @@ #include <asm/syscalls.h> #include <asm/idle.h> #include <asm/uaccess.h> +#include <asm/mwait.h> #include <asm/i387.h> #include <asm/fpu-internal.h> #include <asm/debugreg.h> @@ -398,6 +399,53 @@ static void amd_e400_idle(void) default_idle(); } +/* + * Intel Core2 and older machines prefer MWAIT over HALT for C1. + * We can't rely on cpuidle installing MWAIT, because it will not load + * on systems that support only C1 -- so the boot default must be MWAIT. + * + * Some AMD machines are the opposite, they depend on using HALT. + * + * So for default C1, which is used during boot until cpuidle loads, + * use MWAIT-C1 on Intel HW that has it, else use HALT. + */ +static int prefer_mwait_c1_over_halt(const struct cpuinfo_x86 *c) +{ + if (c->x86_vendor != X86_VENDOR_INTEL) + return 0; + + if (!cpu_has(c, X86_FEATURE_MWAIT)) + return 0; + + return 1; +} + +/* + * MONITOR/MWAIT with no hints, used for default default C1 state. + * This invokes MWAIT with interrutps enabled and no flags, + * which is backwards compatible with the original MWAIT implementation. + */ + +static void mwait_idle(void) +{ + if (!current_set_polling_and_test()) { + if (this_cpu_has(X86_BUG_CLFLUSH_MONITOR)) { + smp_mb(); /* quirk */ + clflush((void *)¤t_thread_info()->flags); + smp_mb(); /* quirk */ + } + + __monitor((void *)¤t_thread_info()->flags, 0, 0); + if (!need_resched()) + __sti_mwait(0, 0); + else + local_irq_enable(); + } else { + local_irq_enable(); + } + __current_clr_polling(); +} + void select_idle_routine(const struct cpuinfo_x86 *c) { #ifdef CONFIG_SMP @@ -411,6 +459,9 @@ void select_idle_routine(const struct cpuinfo_x86 *c) /* E400: APIC timer interrupt does not wake up CPU from C1e */ pr_info("using AMD E400 aware idle routine\n"); x86_idle = amd_e400_idle; + } else if (prefer_mwait_c1_over_halt(c)) { + pr_info("using mwait in idle threads\n"); + x86_idle = mwait_idle; } else x86_idle = default_idle; } diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index ed7039465f16..47843b04d60f 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2381,8 +2381,7 @@ static __init void nested_vmx_setup_ctls_msrs(void) if (enable_ept) { /* nested EPT: emulate EPT also to L1 */ - nested_vmx_secondary_ctls_high |= SECONDARY_EXEC_ENABLE_EPT | - SECONDARY_EXEC_UNRESTRICTED_GUEST; + nested_vmx_secondary_ctls_high |= SECONDARY_EXEC_ENABLE_EPT; nested_vmx_ept_caps = VMX_EPT_PAGE_WALK_4_BIT | VMX_EPTP_WB_BIT | VMX_EPT_2MB_PAGE_BIT | VMX_EPT_INVEPT_BIT; @@ -2396,6 +2395,10 @@ static __init void nested_vmx_setup_ctls_msrs(void) } else nested_vmx_ept_caps = 0; + if (enable_unrestricted_guest) + nested_vmx_secondary_ctls_high |= + SECONDARY_EXEC_UNRESTRICTED_GUEST; + /* miscellaneous data */ rdmsr(MSR_IA32_VMX_MISC, nested_vmx_misc_low, nested_vmx_misc_high); nested_vmx_misc_low &= VMX_MISC_SAVE_EFER_LMA; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index a38dd816015b..5369ec6a8094 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5779,7 +5779,6 @@ int kvm_arch_init(void *opaque) kvm_set_mmio_spte_mask(); kvm_x86_ops = ops; - kvm_init_msr_list(); kvm_mmu_set_mask_ptes(PT_USER_MASK, PT_ACCESSED_MASK, PT_DIRTY_MASK, PT64_NX_MASK, 0); @@ -7210,7 +7209,14 @@ void kvm_arch_hardware_disable(void) int kvm_arch_hardware_setup(void) { - return kvm_x86_ops->hardware_setup(); + int r; + + r = kvm_x86_ops->hardware_setup(); + if (r != 0) + return r; + + kvm_init_msr_list(); + return 0; } void kvm_arch_hardware_unsetup(void) diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c index 006cc914994b..9161f764121e 100644 --- a/arch/x86/mm/hugetlbpage.c +++ b/arch/x86/mm/hugetlbpage.c @@ -52,20 +52,8 @@ int pud_huge(pud_t pud) return 0; } -struct page * -follow_huge_pmd(struct mm_struct *mm, unsigned long address, - pmd_t *pmd, int write) -{ - return NULL; -} #else -struct page * -follow_huge_addr(struct mm_struct *mm, unsigned long address, int write) -{ - return ERR_PTR(-EINVAL); -} - /* * pmd_huge() returns 1 if @pmd is hugetlb related entry, that is normal * hugetlb entry or non-present (migration or hwpoisoned) hugetlb entry. |