[PATCH] kvm: arm/arm64: Simplify lock relaxation in stage2_wp_range

[Suzuki K Poulose]

From: Marc Zyngier <marc.zyngier at arm.com>

Add checks to make sure that kvm->mmu_lock is held while calling
stage2_wp_range. Also avoid explicit checks already done by cond_resched_lock().

Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
[ Added assert_spin_locked check ]
Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>
---
 arch/arm/kvm/mmu.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 7628ef1..37e67f5 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -1162,6 +1162,8 @@ static void stage2_wp_range(struct kvm *kvm, phys_addr_t addr, phys_addr_t end)
 	pgd_t *pgd;
 	phys_addr_t next;
 
+	assert_spin_locked(&kvm->mmu_lock);
+
 	pgd = kvm->arch.pgd + stage2_pgd_index(addr);
 	do {
 		/*
@@ -1171,8 +1173,7 @@ static void stage2_wp_range(struct kvm *kvm, phys_addr_t addr, phys_addr_t end)
 		 * CONFIG_LOCKDEP. Additionally, holding the lock too long
 		 * will also starve other vCPUs.
 		 */
-		if (need_resched() || spin_needbreak(&kvm->mmu_lock))
-			cond_resched_lock(&kvm->mmu_lock);
+		cond_resched_lock(&kvm->mmu_lock);
 
 		next = stage2_pgd_addr_end(addr, end);
 		if (stage2_pgd_present(*pgd))
-- 
2.7.4