1 files changed, 24 insertions, 0 deletions
diff --git a/linker/linker.cpp b/linker/linker.cpp
index d0c740baf..428dd25de 100644
--- a/linker/linker.cpp
+++ b/linker/linker.cpp
@@ -536,6 +536,10 @@ class SizeBasedAllocator {
     allocator_.free(ptr);
   }
 
+  static void purge() {
+    allocator_.purge();
+  }
+
  private:
   static LinkerBlockAllocator allocator_;
 };
@@ -553,6 +557,10 @@ class TypeBasedAllocator {
   static void free(T* ptr) {
     SizeBasedAllocator<sizeof(T)>::free(ptr);
   }
+
+  static void purge() {
+    SizeBasedAllocator<sizeof(T)>::purge();
+  }
 };
 
 class LoadTask {
@@ -2074,6 +2082,8 @@ void* do_dlopen(const char* name, int flags,
          ns == nullptr ? "(null)" : ns->get_name(),
          ns);
 
+  auto purge_guard = android::base::make_scope_guard([&]() { purge_unused_memory(); });
+
   auto failure_guard = android::base::make_scope_guard(
       [&]() { LD_LOG(kLogDlopen, "... dlopen failed: %s", linker_get_error_buffer()); });
 
@@ -4069,3 +4079,17 @@ android_namespace_t* get_exported_namespace(const char* name) {
   }
   return it->second;
 }
+
+void purge_unused_memory() {
+  // For now, we only purge the memory used by LoadTask because we know those
+  // are temporary objects.
+  //
+  // Purging other LinkerBlockAllocator hardly yields much because they hold
+  // information about namespaces and opened libraries, which are not freed
+  // when the control leaves the linker.
+  //
+  // Purging BionicAllocator may give us a few dirty pages back, but those pages
+  // would be already zeroed out, so they compress easily in ZRAM.  Therefore,
+  // it is not worth munmap()'ing those pages.
+  TypeBasedAllocator<LoadTask>::purge();
+}