From e1572f1d08be57a5412a464cff0712a23cd0b73e Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Mon, 16 Sep 2019 18:22:56 +0200 Subject: cpu/SMT: create and export cpu_smt_possible() KVM needs to know if SMT is theoretically possible, this means it is supported and not forcefully disabled ('nosmt=force'). Create and export cpu_smt_possible() answering this question. Signed-off-by: Vitaly Kuznetsov Signed-off-by: Paolo Bonzini --- kernel/cpu.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/cpu.c b/kernel/cpu.c index e1967e9eddc2..fc28e17940e0 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -392,8 +392,7 @@ enum cpuhp_smt_control cpu_smt_control __read_mostly = CPU_SMT_ENABLED; void __init cpu_smt_disable(bool force) { - if (cpu_smt_control == CPU_SMT_FORCE_DISABLED || - cpu_smt_control == CPU_SMT_NOT_SUPPORTED) + if (!cpu_smt_possible()) return; if (force) { @@ -438,6 +437,14 @@ static inline bool cpu_smt_allowed(unsigned int cpu) */ return !cpumask_test_cpu(cpu, &cpus_booted_once_mask); } + +/* Returns true if SMT is not supported of forcefully (irreversibly) disabled */ +bool cpu_smt_possible(void) +{ + return cpu_smt_control != CPU_SMT_FORCE_DISABLED && + cpu_smt_control != CPU_SMT_NOT_SUPPORTED; +} +EXPORT_SYMBOL_GPL(cpu_smt_possible); #else static inline bool cpu_smt_allowed(unsigned int cpu) { return true; } #endif -- cgit v1.2.3