linux-kernel - [PATCH 11/22] KVM: x86: hyper-v: replace bitmap

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Date:   Tue, 10 May 2022 08:47:39 -0700
From:   Yury Norov <yury.norov@...il.com>
To:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        David Laight <David.Laight@...LAB.COM>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Joe Perches <joe@...ches.com>,
        Julia Lawall <Julia.Lawall@...ia.fr>,
        Michał Mirosław <mirq-linux@...e.qmqm.pl>,
        Nicholas Piggin <npiggin@...il.com>,
        Nicolas Palix <nicolas.palix@...g.fr>,
        Peter Zijlstra <peterz@...radead.org>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Matti Vaittinen <Matti.Vaittinen@...rohmeurope.com>,
        linux-kernel@...r.kernel.org
Cc:     Yury Norov <yury.norov@...il.com>, Borislav Petkov <bp@...en8.de>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        "H . Peter Anvin" <hpa@...or.com>, Ingo Molnar <mingo@...hat.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Sean Christopherson <seanjc@...gle.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>, kvm@...r.kernel.org,
        x86@...nel.org
Subject: [PATCH 11/22] KVM: x86: hyper-v: replace bitmap_weight() with hweight64()

kvm_hv_flush_tlb() applies bitmap API to a u64 variable valid_bank_mask.
Since valid_bank_mask has a fixed size, we can use hweight64() and avoid
excessive bloating.

CC: Borislav Petkov <bp@...en8.de>
CC: Dave Hansen <dave.hansen@...ux.intel.com>
CC: H. Peter Anvin <hpa@...or.com>
CC: Ingo Molnar <mingo@...hat.com>
CC: Jim Mattson <jmattson@...gle.com>
CC: Joerg Roedel <joro@...tes.org>
CC: Paolo Bonzini <pbonzini@...hat.com>
CC: Sean Christopherson <seanjc@...gle.com>
CC: Thomas Gleixner <tglx@...utronix.de>
CC: Vitaly Kuznetsov <vkuznets@...hat.com>
CC: Wanpeng Li <wanpengli@...cent.com>
CC: kvm@...r.kernel.org
CC: linux-kernel@...r.kernel.org
CC: x86@...nel.org
Signed-off-by: Yury Norov <yury.norov@...il.com>
---
 arch/x86/kvm/hyperv.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 41585f0edf1e..b652b856df2b 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1855,7 +1855,7 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
 		all_cpus = flush_ex.hv_vp_set.format !=
 			HV_GENERIC_SET_SPARSE_4K;
 
-		if (hc->var_cnt != bitmap_weight((unsigned long *)&valid_bank_mask, 64))
+		if (hc->var_cnt != hweight64(valid_bank_mask))
 			return HV_STATUS_INVALID_HYPERCALL_INPUT;
 
 		if (all_cpus)
@@ -1956,7 +1956,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
 		valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
 		all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
 
-		if (hc->var_cnt != bitmap_weight(&valid_bank_mask, 64))
+		if (hc->var_cnt != hweight64(valid_bank_mask))
 			return HV_STATUS_INVALID_HYPERCALL_INPUT;
 
 		if (all_cpus)
-- 
2.32.0