This is a note to let you know that I've just added the patch titled KVM: x86/mmu: Merge flush and non-flush tdp_mmu_iter_cond_resched to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: kvm-x86-mmu-merge-flush-and-non-flush-tdp_mmu_iter_c.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 2e2b695fb5d990619460c0f8515c25fadd44634e Author: Ben Gardon <bgardon@xxxxxxxxxx> Date: Tue Feb 2 10:57:17 2021 -0800 KVM: x86/mmu: Merge flush and non-flush tdp_mmu_iter_cond_resched [ Upstream commit e139a34ef9d5627a41e1c02210229082140d1f92 ] The flushing and non-flushing variants of tdp_mmu_iter_cond_resched have almost identical implementations. Merge the two functions and add a flush parameter. Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx> Message-Id: <20210202185734.1680553-12-bgardon@xxxxxxxxxx> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 22efd016f05e..3b14d0008f92 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -404,33 +404,13 @@ static inline void tdp_mmu_set_spte_no_dirty_log(struct kvm *kvm, for_each_tdp_pte(_iter, __va(_mmu->root_hpa), \ _mmu->shadow_root_level, _start, _end) -/* - * Flush the TLB and yield if the MMU lock is contended or this thread needs to - * return control to the scheduler. - * - * If this function yields, it will also reset the tdp_iter's walk over the - * paging structure and the calling function should allow the iterator to - * continue its traversal from the paging structure root. - * - * Return true if this function yielded, the TLBs were flushed, and the - * iterator's traversal was reset. Return false if a yield was not needed. - */ -static bool tdp_mmu_iter_flush_cond_resched(struct kvm *kvm, struct tdp_iter *iter) -{ - if (need_resched() || spin_needbreak(&kvm->mmu_lock)) { - kvm_flush_remote_tlbs(kvm); - cond_resched_lock(&kvm->mmu_lock); - tdp_iter_refresh_walk(iter); - return true; - } - - return false; -} - /* * Yield if the MMU lock is contended or this thread needs to return control * to the scheduler. * + * If this function should yield and flush is set, it will perform a remote + * TLB flush before yielding. + * * If this function yields, it will also reset the tdp_iter's walk over the * paging structure and the calling function should allow the iterator to * continue its traversal from the paging structure root. @@ -438,9 +418,13 @@ static bool tdp_mmu_iter_flush_cond_resched(struct kvm *kvm, struct tdp_iter *it * Return true if this function yielded and the iterator's traversal was reset. * Return false if a yield was not needed. */ -static bool tdp_mmu_iter_cond_resched(struct kvm *kvm, struct tdp_iter *iter) +static inline bool tdp_mmu_iter_cond_resched(struct kvm *kvm, + struct tdp_iter *iter, bool flush) { if (need_resched() || spin_needbreak(&kvm->mmu_lock)) { + if (flush) + kvm_flush_remote_tlbs(kvm); + cond_resched_lock(&kvm->mmu_lock); tdp_iter_refresh_walk(iter); return true; @@ -483,7 +467,7 @@ static bool zap_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, tdp_mmu_set_spte(kvm, &iter, 0); flush_needed = !can_yield || - !tdp_mmu_iter_flush_cond_resched(kvm, &iter); + !tdp_mmu_iter_cond_resched(kvm, &iter, true); } return flush_needed; } @@ -852,7 +836,7 @@ static bool wrprot_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, tdp_mmu_set_spte_no_dirty_log(kvm, &iter, new_spte); spte_set = true; - tdp_mmu_iter_cond_resched(kvm, &iter); + tdp_mmu_iter_cond_resched(kvm, &iter, false); } return spte_set; } @@ -911,7 +895,7 @@ static bool clear_dirty_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, tdp_mmu_set_spte_no_dirty_log(kvm, &iter, new_spte); spte_set = true; - tdp_mmu_iter_cond_resched(kvm, &iter); + tdp_mmu_iter_cond_resched(kvm, &iter, false); } return spte_set; } @@ -1027,7 +1011,7 @@ static bool set_dirty_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, tdp_mmu_set_spte(kvm, &iter, new_spte); spte_set = true; - tdp_mmu_iter_cond_resched(kvm, &iter); + tdp_mmu_iter_cond_resched(kvm, &iter, false); } return spte_set; @@ -1080,7 +1064,7 @@ static void zap_collapsible_spte_range(struct kvm *kvm, tdp_mmu_set_spte(kvm, &iter, 0); - spte_set = !tdp_mmu_iter_flush_cond_resched(kvm, &iter); + spte_set = !tdp_mmu_iter_cond_resched(kvm, &iter, true); } if (spte_set)