linux-kernel - [PATCH 15/61] KVM: x86: Refactor CPUID 0x4 and 0x8000001d handling

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Date:   Sat,  1 Feb 2020 10:51:32 -0800
From:   Sean Christopherson <sean.j.christopherson@...el.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <sean.j.christopherson@...el.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH 15/61] KVM: x86: Refactor CPUID 0x4 and 0x8000001d handling

Refactoring the sub-leaf handling for CPUID 0x4/0x8000001d to eliminate
a one-off variable and its associated brackets.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
---
 arch/x86/kvm/cpuid.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 5044a595799f..d75d539da759 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -545,20 +545,16 @@ static inline int __do_cpuid_func(struct kvm_cpuid_entry2 *entry, u32 function,
 		break;
 	/* functions 4 and 0x8000001d have additional index. */
 	case 4:
-	case 0x8000001d: {
-		int cache_type;
-
-		/* read more entries until cache_type is zero */
-		for (i = 1; ; ++i) {
-			cache_type = entry[i - 1].eax & 0x1f;
-			if (!cache_type)
-				break;
-
+	case 0x8000001d:
+		/*
+		 * Read entries until the cache type in the previous entry is
+		 * zero, i.e. indicates an invalid entry.
+		 */
+		for (i = 1; entry[i - 1].eax & 0x1f; ++i) {
 			if (!do_host_cpuid(&entry[i], nent, maxnent, function, i))
 				goto out;
 		}
 		break;
-	}
 	case 6: /* Thermal management */
 		entry->eax = 0x4; /* allow ARAT */
 		entry->ebx = 0;
-- 
2.24.1