OpenE2K/qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity

i386: kill off hv_cpuid_check_and_set()

Browse Source 
hv_cpuid_check_and_set() does too much:
- Checks if the feature is supported by KVM;
- Checks if all dependencies are enabled;
- Sets the feature bit in cpu->hyperv_features for 'passthrough' mode.

To reduce the complexity, move all the logic except for dependencies
check out of it. Also, in 'passthrough' mode we don't really need to
check dependencies because KVM is supposed to provide a consistent
set anyway.

Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210608120817.1325125-7-vkuznets@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
This commit is contained in:
Vitaly Kuznetsov 2021-06-08 14:08:14 +02:00 committed by Eduardo Habkost
parent 071ce4b03b
commit 5ce48fa354
1 changed files with 36 additions and 68 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

104
target/i386/kvm/kvm.c
View File

@ -1148,16 +1148,12 @@ static bool hyperv_feature_supported(CPUState *cs, int feature)
return true;
}
static int hv_cpuid_check_and_set(CPUState *cs, int feature, Error **errp)
/* Checks that all feature dependencies are enabled */
static bool hv_feature_check_deps(X86CPU *cpu, int feature, Error **errp)
{
X86CPU *cpu = X86_CPU(cs);
uint64_t deps;
int dep_feat;
if (!hyperv_feat_enabled(cpu, feature) && !cpu->hyperv_passthrough) {
return 0;
}
deps = kvm_hyperv_properties[feature].dependencies;
while (deps) {
dep_feat = ctz64(deps);
@ -1165,26 +1161,12 @@ static int hv_cpuid_check_and_set(CPUState *cs, int feature, Error **errp)
error_setg(errp, "Hyper-V %s requires Hyper-V %s",
kvm_hyperv_properties[feature].desc,
kvm_hyperv_properties[dep_feat].desc);
return 1;
return false;
}
deps &= ~(1ull << dep_feat);
}
if (!hyperv_feature_supported(cs, feature)) {
if (hyperv_feat_enabled(cpu, feature)) {
error_setg(errp, "Hyper-V %s is not supported by kernel",
kvm_hyperv_properties[feature].desc);
return 1;
} else {
return 0;
}
}
if (cpu->hyperv_passthrough) {
cpu->hyperv_features |= BIT(feature);
}
return 0;
return true;
}
static uint32_t hv_build_cpuid_leaf(CPUState *cs, uint32_t func, int reg)
@ -1223,6 +1205,8 @@ static uint32_t hv_build_cpuid_leaf(CPUState *cs, uint32_t func, int reg)
bool kvm_hyperv_expand_features(X86CPU *cpu, Error **errp)
{
CPUState *cs = CPU(cpu);
Error *local_err = NULL;
int feat;
if (!hyperv_enabled(cpu))
return true;
@ -1278,53 +1262,37 @@ bool kvm_hyperv_expand_features(X86CPU *cpu, Error **errp)
cpu->hyperv_spinlock_attempts =
hv_cpuid_get_host(cs, HV_CPUID_ENLIGHTMENT_INFO, R_EBX);
}
/* Features */
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_RELAXED, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_VAPIC, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_TIME, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_CRASH, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_RESET, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_VPINDEX, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_RUNTIME, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_SYNIC, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_STIMER, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_FREQUENCIES, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_REENLIGHTENMENT, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_TLBFLUSH, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_EVMCS, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_IPI, errp)) {
return false;
}
if (hv_cpuid_check_and_set(cs, HYPERV_FEAT_STIMER_DIRECT, errp)) {
return false;
/*
* Mark feature as enabled in 'cpu->hyperv_features' as
* hv_build_cpuid_leaf() uses this info to build guest CPUIDs.
*/
for (feat = 0; feat < ARRAY_SIZE(kvm_hyperv_properties); feat++) {
if (hyperv_feature_supported(cs, feat)) {
cpu->hyperv_features |= BIT(feat);
}
}
} else {
/* Check features availability and dependencies */
for (feat = 0; feat < ARRAY_SIZE(kvm_hyperv_properties); feat++) {
/* If the feature was not requested skip it. */
if (!hyperv_feat_enabled(cpu, feat)) {
continue;
}
/* Check if the feature is supported by KVM */
if (!hyperv_feature_supported(cs, feat)) {
error_setg(errp, "Hyper-V %s is not supported by kernel",
kvm_hyperv_properties[feat].desc);
return false;
}
/* Check dependencies */
if (!hv_feature_check_deps(cpu, feat, &local_err)) {
error_propagate(errp, local_err);
return false;
}
}
}
/* Additional dependencies not covered by kvm_hyperv_properties[] */