Add support for modifying decay timer.

Add the mallopt function, and only a single option so far.

Bug: 36401135

Test: Built and booted bullhead.
Test: Ran jemalloc unit tests.
Test: Ran bionic unit tests.
Test: Ran a test that allocated and free'd a large piece of memory,
Test: and verified that after changing the parameter, the PSS
Test: sticks around (decay timer set to 1), the PSS is purged (decay
Test: timer set to 0).
Change-Id: I6927929b0c539c1023d34772d9e26bb6a8a45877

1 files changed, 16 insertions, 0 deletions

diff --git a/libc/malloc_debug/tests/malloc_debug_unit_tests.cpp b/libc/malloc_debug/tests/malloc_debug_unit_tests.cpp
index 219c21ebb..4fdba2ef9 100644
--- a/libc/malloc_debug/tests/malloc_debug_unit_tests.cpp
+++ b/libc/malloc_debug/tests/malloc_debug_unit_tests.cpp
@@ -58,6 +58,7 @@ void debug_get_malloc_leak_info(uint8_t**, size_t*, size_t*, size_t*, size_t*);
 void debug_free_malloc_leak_info(uint8_t*);
 
 struct mallinfo debug_mallinfo();
+int debug_mallopt(int, int);
 
 #if defined(HAVE_DEPRECATED_MALLOC_FUNCS)
 void* debug_pvalloc(size_t);
@@ -128,6 +129,7 @@ MallocDispatch MallocDebugTest::dispatch = {
   nullptr,
   nullptr,
   nullptr,
+  mallopt,
 };
 
 void VerifyAllocCalls() {
@@ -1474,6 +1476,20 @@ TEST_F(MallocDebugTest, debug_mallinfo) {
   ASSERT_STREQ("", getFakeLogPrint().c_str());
 }
 
+TEST_F(MallocDebugTest, debug_mallopt) {
+  Init("guard");
+
+  void* pointer = debug_malloc(150);
+  ASSERT_TRUE(pointer != nullptr);
+
+  EXPECT_EQ(0, debug_mallopt(-1000, 1));
+
+  debug_free(pointer);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
 TEST_F(MallocDebugTest, debug_posix_memalign) {
   Init("guard");