diff --git a/src/cargo/core/global_cache_tracker.rs b/src/cargo/core/global_cache_tracker.rs
index e94a86c71dd..639cd599cc9 100644
--- a/src/cargo/core/global_cache_tracker.rs
+++ b/src/cargo/core/global_cache_tracker.rs
@@ -558,6 +558,42 @@ impl GlobalCacheTracker {
         Ok(rows)
     }
 
+    // Return all workspace_manifest cache timestamps.
+    pub fn workspace_manifest_all(&self) -> CargoResult<Vec<(WorkspaceManifestIndex, Timestamp)>> {
+        let mut stmt = self
+            .conn
+            .prepare_cached("SELECT name, timestamp FROM workspace_manifest_index")?;
+        let rows = stmt
+            .query_map([], |row| {
+                let workspace_manifest_path = row.get_unwrap(0);
+                let timestamp = row.get_unwrap(1);
+                let kind = WorkspaceManifestIndex {
+                    workspace_manifest_path: workspace_manifest_path,
+                };
+                Ok((kind, timestamp))
+            })?
+            .collect::<Result<Vec<_>, _>>()?;
+        Ok(rows)
+    }
+
+    // Return all target dir cache timestamps.
+    pub fn target_dir_all(&self) -> CargoResult<Vec<(TargetDirIndex, Timestamp)>> {
+        let mut stmt = self
+            .conn
+            .prepare_cached("SELECT name, timestamp FROM target_dir_index")?;
+        let rows = stmt
+            .query_map([], |row| {
+                let target_dir_path = row.get_unwrap(0);
+                let timestamp = row.get_unwrap(1);
+                let kind = TargetDirIndex {
+                    target_dir_path: target_dir_path,
+                };
+                Ok((kind, timestamp))
+            })?
+            .collect::<Result<Vec<_>, _>>()?;
+        Ok(rows)
+    }
+
     /// Returns whether or not an auto GC should be performed, compared to the
     /// last time it was recorded in the database.
     pub fn should_run_auto_gc(&mut self, frequency: Duration) -> CargoResult<bool> {
diff --git a/tests/testsuite/global_cache_tracker.rs b/tests/testsuite/global_cache_tracker.rs
index a7e5407af58..8a94c23dba3 100644
--- a/tests/testsuite/global_cache_tracker.rs
+++ b/tests/testsuite/global_cache_tracker.rs
@@ -223,6 +223,10 @@ fn implies_source() {
         short_name: "f0a4ee0".into(),
         size: None,
     });
+    deferred.mark_workspace_src_used(global_cache_tracker::WorkspaceSrc {
+        target_dir_path: "/Users/foo/cargo/target".into(),
+        workspace_manifest_path: "/Users/foo/cargo/Cargo.toml".into(),
+    });
     deferred.save(&mut tracker).unwrap();
 
     let mut indexes = tracker.registry_index_all().unwrap();
@@ -240,6 +244,17 @@ fn implies_source() {
     let dbs = tracker.git_db_all().unwrap();
     assert_eq!(dbs.len(), 1);
     assert_eq!(dbs[0].0.encoded_git_name, "cargo-e7ff1db891893a9e");
+
+    let workspace_manifests = tracker.workspace_manifest_all().unwrap();
+    assert_eq!(workspace_manifests.len(), 1);
+    assert_eq!(
+        workspace_manifests[0].0.workspace_manifest_name,
+        "/Users/foo/cargo/Cargo.toml"
+    );
+
+    let target_dirs = tracker.target_dir_all().unwrap();
+    assert_eq!(target_dirs.len(), 1);
+    assert_eq!(target_dirs[0].0.target_dir_name, "/Users/foo/cargo/target");
 }
 
 #[cargo_test]