KVM will use split_lock_detect_disabled() and split_lock_detect_on() in vmx_vcpu_run() to check whether split lock detect can be exposed to guest and whether host has turned it on. Make them static inline to avoid the extra CALL+RET in that path. sld_msr_set() will be used when switching from/to guest. Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx> --- arch/x86/include/asm/cpu.h | 23 +++++++++++++++++++++++ arch/x86/kernel/cpu/intel.c | 17 ++++++++--------- 2 files changed, 31 insertions(+), 9 deletions(-) diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h index ff567afa6ee1..2e17315b1fed 100644 --- a/arch/x86/include/asm/cpu.h +++ b/arch/x86/include/asm/cpu.h @@ -41,15 +41,38 @@ unsigned int x86_family(unsigned int sig); unsigned int x86_model(unsigned int sig); unsigned int x86_stepping(unsigned int sig); #ifdef CONFIG_CPU_SUP_INTEL +enum split_lock_detect_state { + sld_not_exist = 0, + sld_disable, + sld_kvm_only, + sld_warn, + sld_fatal, +}; +extern enum split_lock_detect_state sld_state; + +static inline bool split_lock_detect_on(void) +{ + return (sld_state == sld_warn) || (sld_state == sld_fatal); +} + +static inline bool split_lock_detect_disabled(void) +{ + return sld_state == sld_disable; +} + extern void __init cpu_set_core_cap_bits(struct cpuinfo_x86 *c); extern void switch_to_sld(unsigned long tifn); extern bool handle_user_split_lock(unsigned long ip); +extern void sld_msr_set(bool on); #else +static inline bool split_lock_detect_on(void) { return false; } +static inline bool split_lock_detect_disabled(void) { return true; } static inline void __init cpu_set_core_cap_bits(struct cpuinfo_x86 *c) {} static inline void switch_to_sld(unsigned long tifn) {} static inline bool handle_user_split_lock(unsigned long ip) { return false; } +static inline void sld_msr_set(bool on) {} #endif #endif /* _ASM_X86_CPU_H */ diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index c401d174c8db..8bfe8b07e06e 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -33,19 +33,12 @@ #include <asm/apic.h> #endif -enum split_lock_detect_state { - sld_not_exist = 0, - sld_disable, - sld_kvm_only, - sld_warn, - sld_fatal, -}; - /* * split_lock_setup() will switch this to sld_warn on systems that support * split lock detect, unless there is a command line override. */ -static enum split_lock_detect_state sld_state = sld_not_exist; +enum split_lock_detect_state sld_state = sld_not_exist; +EXPORT_SYMBOL_GPL(sld_state); /* * Processors which have self-snooping capability can handle conflicting @@ -1121,6 +1114,12 @@ bool handle_user_split_lock(unsigned long ip) } EXPORT_SYMBOL_GPL(handle_user_split_lock); +void sld_msr_set(bool on) +{ + __sld_msr_set(on); +} +EXPORT_SYMBOL_GPL(sld_msr_set); + /* * This function is called only when switching between tasks with * different split-lock detection modes. It sets the MSR for the -- 2.20.1