5 files changed, 64 insertions, 10 deletions
diff --git a/benchmarks/Android.bp b/benchmarks/Android.bp
index ffb592108..75e607cd1 100644
--- a/benchmarks/Android.bp
+++ b/benchmarks/Android.bp
@@ -72,6 +72,7 @@ cc_defaults {
 
     target: {
         android: {
+            header_libs: ["bionic_libc_platform_headers"],
             static_libs: [
                 "libmeminfo",
                 "libprocinfo",
diff --git a/benchmarks/ScopedDecayTimeRestorer.h b/benchmarks/ScopedDecayTimeRestorer.h
new file mode 100644
index 000000000..5835b4316
--- /dev/null
+++ b/benchmarks/ScopedDecayTimeRestorer.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <malloc.h>
+
+#if defined(__BIONIC__)
+
+#include "platform/bionic/malloc.h"
+
+class ScopedDecayTimeRestorer {
+ public:
+  ScopedDecayTimeRestorer() {
+    bool value;
+    if (android_mallopt(M_GET_DECAY_TIME_ENABLED, &value, sizeof(value))) {
+      saved_value_ = value ? 1 : 0;
+    }
+  }
+
+  virtual ~ScopedDecayTimeRestorer() { mallopt(M_DECAY_TIME, saved_value_); }
+
+ private:
+  int saved_value_ = 0;
+};
+
+#endif
diff --git a/benchmarks/malloc_benchmark.cpp b/benchmarks/malloc_benchmark.cpp
index 258343fca..8f467d2ab 100644
--- a/benchmarks/malloc_benchmark.cpp
+++ b/benchmarks/malloc_benchmark.cpp
@@ -36,11 +36,14 @@
 #include <vector>
 
 #include <benchmark/benchmark.h>
+#include "ScopedDecayTimeRestorer.h"
 #include "util.h"
 
 #if defined(__BIONIC__)
 
 static void RunMalloptPurge(benchmark::State& state, int purge_value) {
+  ScopedDecayTimeRestorer restorer;
+
   static size_t sizes[] = {8, 16, 32, 64, 128, 1024, 4096, 16384, 65536, 131072, 1048576};
   static int pagesize = getpagesize();
   mallopt(M_DECAY_TIME, 1);
@@ -69,7 +72,6 @@ static void RunMalloptPurge(benchmark::State& state, int purge_value) {
 
     mallopt(purge_value, 0);
   }
-  mallopt(M_DECAY_TIME, 0);
 }
 
 static void RunThreadsThroughput(benchmark::State& state, size_t size, size_t num_threads) {
diff --git a/benchmarks/malloc_sql_benchmark.cpp b/benchmarks/malloc_sql_benchmark.cpp
index 383325ccb..d5b17f677 100644
--- a/benchmarks/malloc_sql_benchmark.cpp
+++ b/benchmarks/malloc_sql_benchmark.cpp
@@ -31,6 +31,7 @@
 #include <unistd.h>
 
 #include <benchmark/benchmark.h>
+#include "ScopedDecayTimeRestorer.h"
 #include "util.h"
 
 #if defined(__BIONIC__)
@@ -104,6 +105,8 @@ void BenchmarkMalloc(MallocEntry entries[], size_t total_entries, size_t max_all
 #include "malloc_sql.h"
 
 static void BM_malloc_sql_trace_default(benchmark::State& state) {
+  ScopedDecayTimeRestorer restorer;
+
   // The default is expected to be a zero decay time.
   mallopt(M_DECAY_TIME, 0);
 
@@ -115,14 +118,14 @@ static void BM_malloc_sql_trace_default(benchmark::State& state) {
 BIONIC_BENCHMARK(BM_malloc_sql_trace_default);
 
 static void BM_malloc_sql_trace_decay1(benchmark::State& state) {
+  ScopedDecayTimeRestorer restorer;
+
   mallopt(M_DECAY_TIME, 1);
 
   for (auto _ : state) {
     BenchmarkMalloc(g_sql_entries, sizeof(g_sql_entries) / sizeof(MallocEntry),
                     kMaxSqlAllocSlots);
   }
-
-  mallopt(M_DECAY_TIME, 0);
 }
 BIONIC_BENCHMARK(BM_malloc_sql_trace_decay1);
 
diff --git a/benchmarks/stdlib_benchmark.cpp b/benchmarks/stdlib_benchmark.cpp
index 14b380a45..9be72e7aa 100644
--- a/benchmarks/stdlib_benchmark.cpp
+++ b/benchmarks/stdlib_benchmark.cpp
@@ -22,6 +22,7 @@
 #include <unistd.h>
 
 #include <benchmark/benchmark.h>
+#include "ScopedDecayTimeRestorer.h"
 #include "util.h"
 
 static void MallocFree(benchmark::State& state) {
@@ -40,6 +41,8 @@ static void MallocFree(benchmark::State& state) {
 
 static void BM_stdlib_malloc_free_default(benchmark::State& state) {
 #if defined(__BIONIC__)
+  ScopedDecayTimeRestorer restorer;
+
   // The default is expected to be a zero decay time.
   mallopt(M_DECAY_TIME, 0);
 #endif
@@ -50,11 +53,11 @@ BIONIC_BENCHMARK_WITH_ARG(BM_stdlib_malloc_free_default, "AT_COMMON_SIZES");
 
 #if defined(__BIONIC__)
 static void BM_stdlib_malloc_free_decay1(benchmark::State& state) {
+  ScopedDecayTimeRestorer restorer;
+
   mallopt(M_DECAY_TIME, 1);
 
   MallocFree(state);
-
-  mallopt(M_DECAY_TIME, 0);
 }
 BIONIC_BENCHMARK_WITH_ARG(BM_stdlib_malloc_free_decay1, "AT_COMMON_SIZES");
 #endif
@@ -75,6 +78,8 @@ static void CallocFree(benchmark::State& state) {
 
 static void BM_stdlib_calloc_free_default(benchmark::State& state) {
 #if defined(__BIONIC__)
+  ScopedDecayTimeRestorer restorer;
+
   // The default is expected to be a zero decay time.
   mallopt(M_DECAY_TIME, 0);
 #endif
@@ -113,8 +118,9 @@ static void MallocMultiple(benchmark::State& state, size_t nbytes, size_t numAll
 }
 
 void BM_stdlib_malloc_forty_default(benchmark::State& state) {
-
 #if defined(__BIONIC__)
+  ScopedDecayTimeRestorer restorer;
+
   // The default is expected to be a zero decay time.
   mallopt(M_DECAY_TIME, 0);
 #endif
@@ -125,17 +131,19 @@ BIONIC_BENCHMARK_WITH_ARG(BM_stdlib_malloc_forty_default, "AT_COMMON_SIZES");
 
 #if defined(__BIONIC__)
 void BM_stdlib_malloc_forty_decay1(benchmark::State& state) {
+  ScopedDecayTimeRestorer restorer;
+
   mallopt(M_DECAY_TIME, 1);
 
   MallocMultiple(state, state.range(0), 40);
-
-  mallopt(M_DECAY_TIME, 0);
 }
 BIONIC_BENCHMARK_WITH_ARG(BM_stdlib_malloc_forty_decay1, "AT_COMMON_SIZES");
 #endif
 
 void BM_stdlib_malloc_multiple_8192_allocs_default(benchmark::State& state) {
 #if defined(__BIONIC__)
+  ScopedDecayTimeRestorer restorer;
+
   // The default is expected to be a zero decay time.
   mallopt(M_DECAY_TIME, 0);
 #endif
@@ -146,11 +154,11 @@ BIONIC_BENCHMARK_WITH_ARG(BM_stdlib_malloc_multiple_8192_allocs_default, "AT_SMA
 
 #if defined(__BIONIC__)
 void BM_stdlib_malloc_multiple_8192_allocs_decay1(benchmark::State& state) {
+  ScopedDecayTimeRestorer restorer;
+
   mallopt(M_DECAY_TIME, 1);
 
   MallocMultiple(state, 8192, state.range(0));
-
-  mallopt(M_DECAY_TIME, 0);
 }
 BIONIC_BENCHMARK_WITH_ARG(BM_stdlib_malloc_multiple_8192_allocs_decay1, "AT_SMALL_SIZES");
 #endif