Date:   Mon,  6 Mar 2023 14:41:18 -0800
In-Reply-To: <20230306224127.1689967-1-vipinsh@google.com>
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Message-ID: <20230306224127.1689967-10-vipinsh@google.com>
Subject: [Patch v4 09/18] KVM: x86/mmu: Shrink mmu_shadowed_info_cache via MMU shrinker
From:   Vipin Sharma <vipinsh@google.com>
To:     seanjc@google.com, pbonzini@redhat.com, bgardon@google.com,
        dmatlack@google.com
Cc:     jmattson@google.com, mizhang@google.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Vipin Sharma <vipinsh@google.com>
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Precedence: bulk

Shrink shadow page cache via MMU shrinker based on
kvm_total_unused_cached_pages.

Tested by running dirty_log_perf_test while dropping cache
via "echo 2 > /proc/sys/vm/drop_caches" at 1 second interval. Global
always return to 0. Shrinker also gets invoked to remove pages in cache.

Above test were run with three configurations:
- EPT=N
- EPT=Y, TDP_MMU=N
- EPT=Y, TDP_MMU=Y

Signed-off-by: Vipin Sharma <vipinsh@google.com>
---
 arch/x86/kvm/mmu/mmu.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index b7ca31b5699c..a4bf2e433030 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -6725,6 +6725,8 @@ static unsigned long mmu_shrink_scan(struct shrinker *shrink,
 		kvm_for_each_vcpu(i, vcpu, kvm) {
 			freed += mmu_memory_cache_try_empty(&vcpu->arch.mmu_shadow_page_cache,
 							    &vcpu->arch.mmu_shadow_page_cache_lock);
+			freed += mmu_memory_cache_try_empty(&vcpu->arch.mmu_shadowed_info_cache,
+							    &vcpu->arch.mmu_shadow_page_cache_lock);
 			if (freed >= sc->nr_to_scan)
 				goto out;
 		}
-- 
2.40.0.rc0.216.gc4246ad0f0-goog