[PATCH v2 10/66] KVM: x86: Clean up CPUID 0x7 sub-leaf loop

Sean Christopherson
2020-03-03T00:01:25Z

Refactor the sub-leaf loop for CPUID 0x7 to move the main leaf out of
said loop. The emitted code savings is basically a mirage, as the
handling of the main leaf can easily be split to its own helper to avoid
code bloat.

No functional change intended.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/kvm/cpuid.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 6e1685a16cca..b626893a11d5 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -573,16 +573,16 @@ static inline int __do_cpuid_func(struct kvm_cpuid_entry2 *entry, u32 function,
case 7: {
int i;

- for (i = 0; ; ) {
+ do_cpuid_7_mask(entry, 0);
+
+ for (i = 1; i <= entry->eax; i++) {
+ if (*nent >= maxnent)
+ goto out;
+
+ do_host_cpuid(&entry[i], function, i);
+ ++*nent;
+
do_cpuid_7_mask(&entry[i], i);
- if (i == entry->eax)
- break;
- if (*nent >= maxnent)
- goto out;
-
- ++i;
- do_host_cpuid(&entry[i], function, i);
- ++*nent;
}
break;
}
--
2.24.1