From b5a96072328bbeb3b365b62bd5736908f1a1e72e Mon Sep 17 00:00:00 2001
From: Kelvin Zhang <zhangkelvin@google.com>
Date: Thu, 23 Feb 2023 13:20:07 -0800
Subject: [PATCH] Initialize COW options using update manifest

Update manifest contains feature specifications such as whether to use
multi-threading or batched writes, initialize COW options using the
manifest allows these features to be enabled/disabled at update install
time.

Test: th
Change-Id: Iff66c43567d4890ae1c88624db49014584b1d96f
---
 fs_mgr/libsnapshot/android/snapshot/snapshot.proto |  6 ++++++
 fs_mgr/libsnapshot/partition_cow_creator.h         |  6 ++++++
 fs_mgr/libsnapshot/snapshot.cpp                    | 14 ++++++++++++++
 .../update_engine/update_metadata.proto            |  7 +++++++
 4 files changed, 33 insertions(+)

diff --git a/fs_mgr/libsnapshot/android/snapshot/snapshot.proto b/fs_mgr/libsnapshot/android/snapshot/snapshot.proto
index b3763aea4..fa04c437d 100644
--- a/fs_mgr/libsnapshot/android/snapshot/snapshot.proto
+++ b/fs_mgr/libsnapshot/android/snapshot/snapshot.proto
@@ -108,6 +108,12 @@ message SnapshotStatus {
 
     // Estimated COW size from OTA manifest.
     uint64 estimated_cow_size = 12;
+
+    // Enable multi-threaded compression
+    bool enable_threading = 13;
+
+    // Enable batching for COW writes
+    bool batched_writes = 14;
 }
 
 // Next: 8
diff --git a/fs_mgr/libsnapshot/partition_cow_creator.h b/fs_mgr/libsnapshot/partition_cow_creator.h
index 949e6c5be..bd5c8cb2e 100644
--- a/fs_mgr/libsnapshot/partition_cow_creator.h
+++ b/fs_mgr/libsnapshot/partition_cow_creator.h
@@ -60,6 +60,12 @@ struct PartitionCowCreator {
     bool using_snapuserd = false;
     std::string compression_algorithm;
 
+    // True if multi-threaded compression should be enabled
+    bool enable_threading;
+
+    // True if COW writes should be batched in memory
+    bool batched_writes;
+
     struct Return {
         SnapshotStatus snapshot_status;
         std::vector<Interval> cow_partition_usable_regions;
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index 961db02ef..15f025c9c 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -400,6 +400,12 @@ bool SnapshotManager::CreateSnapshot(LockedFile* lock, PartitionCowCreator* cow_
     status->set_metadata_sectors(0);
     status->set_using_snapuserd(cow_creator->using_snapuserd);
     status->set_compression_algorithm(cow_creator->compression_algorithm);
+    if (cow_creator->enable_threading) {
+        status->set_enable_threading(cow_creator->enable_threading);
+    }
+    if (cow_creator->batched_writes) {
+        status->set_batched_writes(cow_creator->batched_writes);
+    }
 
     if (!WriteSnapshotStatus(lock, *status)) {
         PLOG(ERROR) << "Could not write snapshot status: " << status->name();
@@ -3248,6 +3254,12 @@ Return SnapshotManager::CreateUpdateSnapshots(const DeltaArchiveManifest& manife
             .using_snapuserd = using_snapuserd,
             .compression_algorithm = compression_algorithm,
     };
+    if (dap_metadata.vabc_feature_set().has_threaded()) {
+        cow_creator.enable_threading = dap_metadata.vabc_feature_set().threaded();
+    }
+    if (dap_metadata.vabc_feature_set().has_batch_writes()) {
+        cow_creator.batched_writes = dap_metadata.vabc_feature_set().batch_writes();
+    }
 
     auto ret = CreateUpdateSnapshotsInternal(lock.get(), manifest, &cow_creator, &created_devices,
                                              &all_snapshot_status);
@@ -3635,6 +3647,8 @@ std::unique_ptr<ISnapshotWriter> SnapshotManager::OpenCompressedSnapshotWriter(
     CowOptions cow_options;
     cow_options.compression = status.compression_algorithm();
     cow_options.max_blocks = {status.device_size() / cow_options.block_size};
+    cow_options.batch_write = status.batched_writes();
+    cow_options.num_compress_threads = status.enable_threading() ? 2 : 0;
     // Disable scratch space for vts tests
     if (device()->IsTestDevice()) {
         cow_options.scratch_space = false;
diff --git a/fs_mgr/libsnapshot/update_engine/update_metadata.proto b/fs_mgr/libsnapshot/update_engine/update_metadata.proto
index 69d72e19c..cc12d1db2 100644
--- a/fs_mgr/libsnapshot/update_engine/update_metadata.proto
+++ b/fs_mgr/libsnapshot/update_engine/update_metadata.proto
@@ -71,11 +71,18 @@ message DynamicPartitionGroup {
     repeated string partition_names = 3;
 }
 
+message VABCFeatureSet {
+  optional bool threaded = 1;
+  optional bool batch_writes = 2;
+}
+
 message DynamicPartitionMetadata {
     repeated DynamicPartitionGroup groups = 1;
     optional bool vabc_enabled = 3;
     optional string vabc_compression_param = 4;
     optional uint32 cow_version = 5;
+    // A collection of knobs to tune Virtual AB Compression
+    optional VABCFeatureSet vabc_feature_set = 6;
 }
 
 message DeltaArchiveManifest {