diff --git a/core/jni/com_android_internal_os_KernelCpuBpfTracking.cpp b/core/jni/com_android_internal_os_KernelCpuBpfTracking.cpp
index 6b41b2ec8f93..d644e3709045 100644
--- a/core/jni/com_android_internal_os_KernelCpuBpfTracking.cpp
+++ b/core/jni/com_android_internal_os_KernelCpuBpfTracking.cpp
@@ -30,13 +30,13 @@ static jboolean KernelCpuBpfTracking_startTrackingInternal(JNIEnv *, jobject) {
 
 static jlongArray KernelCpuBpfTracking_getFreqsInternal(JNIEnv *env, jobject) {
     auto freqs = android::bpf::getCpuFreqs();
-    if (!freqs) return NULL;
+    if (!freqs) return nullptr;
 
     std::vector<uint64_t> allFreqs;
     for (const auto &vec : *freqs) std::copy(vec.begin(), vec.end(), std::back_inserter(allFreqs));
 
     auto ar = env->NewLongArray(allFreqs.size());
-    if (ar != NULL) {
+    if (ar != nullptr) {
         env->SetLongArrayRegion(ar, 0, allFreqs.size(),
                                 reinterpret_cast<const jlong *>(allFreqs.data()));
     }
@@ -45,7 +45,7 @@ static jlongArray KernelCpuBpfTracking_getFreqsInternal(JNIEnv *env, jobject) {
 
 static jintArray KernelCpuBpfTracking_getFreqsClustersInternal(JNIEnv *env, jobject) {
     auto freqs = android::bpf::getCpuFreqs();
-    if (!freqs) return NULL;
+    if (!freqs) return nullptr;
 
     std::vector<uint32_t> freqsClusters;
     uint32_t clusters = freqs->size();
@@ -54,7 +54,7 @@ static jintArray KernelCpuBpfTracking_getFreqsClustersInternal(JNIEnv *env, jobj
     }
 
     auto ar = env->NewIntArray(freqsClusters.size());
-    if (ar != NULL) {
+    if (ar != nullptr) {
         env->SetIntArrayRegion(ar, 0, freqsClusters.size(),
                                reinterpret_cast<const jint *>(freqsClusters.data()));
     }
diff --git a/core/jni/com_android_internal_os_KernelCpuTotalBpfMapReader.cpp b/core/jni/com_android_internal_os_KernelCpuTotalBpfMapReader.cpp
index ad43014d321f..472bd23c0f8d 100644
--- a/core/jni/com_android_internal_os_KernelCpuTotalBpfMapReader.cpp
+++ b/core/jni/com_android_internal_os_KernelCpuTotalBpfMapReader.cpp
@@ -22,7 +22,7 @@ namespace android {
 
 static jlongArray KernelCpuTotalBpfMapReader_readInternal(JNIEnv *env, jobject) {
     auto freqTimes = android::bpf::getTotalCpuFreqTimes();
-    if (!freqTimes) return JNI_FALSE;
+    if (!freqTimes) return nullptr;
 
     std::vector<uint64_t> allTimes;
     for (const auto &vec : *freqTimes) {
@@ -32,7 +32,7 @@ static jlongArray KernelCpuTotalBpfMapReader_readInternal(JNIEnv *env, jobject)
     }
 
     auto ar = env->NewLongArray(allTimes.size());
-    if (ar != NULL) {
+    if (ar != nullptr) {
         env->SetLongArrayRegion(ar, 0, allTimes.size(),
                                 reinterpret_cast<const jlong *>(allTimes.data()));
     }
diff --git a/core/jni/com_android_internal_os_KernelCpuUidBpfMapReader.cpp b/core/jni/com_android_internal_os_KernelCpuUidBpfMapReader.cpp
index 7900d301dbb0..098a4d868269 100644
--- a/core/jni/com_android_internal_os_KernelCpuUidBpfMapReader.cpp
+++ b/core/jni/com_android_internal_os_KernelCpuUidBpfMapReader.cpp
@@ -37,7 +37,7 @@ static jlongArray getUidArray(JNIEnv *env, jobject sparseAr, uint32_t uid, jsize
     jlongArray ar = (jlongArray)env->CallObjectMethod(sparseAr, gSparseArrayClassInfo.get, uid);
     if (!ar) {
         ar = env->NewLongArray(sz);
-        if (ar == NULL) return ar;
+        if (ar == nullptr) return ar;
         env->CallVoidMethod(sparseAr, gSparseArrayClassInfo.put, uid, ar);
     }
     return ar;
@@ -65,7 +65,7 @@ static jboolean KernelCpuUidFreqTimeBpfMapReader_readBpfData(JNIEnv *env, jobjec
     static uint64_t lastUpdate = 0;
     uint64_t newLastUpdate = lastUpdate;
     auto sparseAr = env->GetObjectField(thiz, gmData);
-    if (sparseAr == NULL) return false;
+    if (sparseAr == nullptr) return false;
     auto data = android::bpf::getUidsUpdatedCpuFreqTimes(&newLastUpdate);
     if (!data.has_value()) return false;
 
@@ -75,7 +75,7 @@ static jboolean KernelCpuUidFreqTimeBpfMapReader_readBpfData(JNIEnv *env, jobjec
             for (const auto &subVec : times) s += subVec.size();
         }
         jlongArray ar = getUidArray(env, sparseAr, uid, s);
-        if (ar == NULL) return false;
+        if (ar == nullptr) return false;
         copy2DVecToArray(env, ar, times);
     }
     lastUpdate = newLastUpdate;
@@ -91,7 +91,7 @@ static jboolean KernelCpuUidActiveTimeBpfMapReader_readBpfData(JNIEnv *env, jobj
     static uint64_t lastUpdate = 0;
     uint64_t newLastUpdate = lastUpdate;
     auto sparseAr = env->GetObjectField(thiz, gmData);
-    if (sparseAr == NULL) return false;
+    if (sparseAr == nullptr) return false;
     auto data = android::bpf::getUidsUpdatedConcurrentTimes(&newLastUpdate);
     if (!data.has_value()) return false;
 
@@ -99,7 +99,7 @@ static jboolean KernelCpuUidActiveTimeBpfMapReader_readBpfData(JNIEnv *env, jobj
         // TODO: revise calling code so we can divide by NSEC_PER_MSEC here instead
         for (auto &time : times.active) time /= NSEC_PER_MSEC;
         jlongArray ar = getUidArray(env, sparseAr, uid, times.active.size());
-        if (ar == NULL) return false;
+        if (ar == nullptr) return false;
         env->SetLongArrayRegion(ar, 0, times.active.size(),
                                 reinterpret_cast<const jlong *>(times.active.data()));
     }
@@ -111,7 +111,7 @@ static jlongArray KernelCpuUidActiveTimeBpfMapReader_getDataDimensions(JNIEnv *e
     jlong nCpus = get_nprocs_conf();
 
     auto ar = env->NewLongArray(1);
-    if (ar != NULL) env->SetLongArrayRegion(ar, 0, 1, &nCpus);
+    if (ar != nullptr) env->SetLongArrayRegion(ar, 0, 1, &nCpus);
     return ar;
 }
 
@@ -124,7 +124,7 @@ static jboolean KernelCpuUidClusterTimeBpfMapReader_readBpfData(JNIEnv *env, job
     static uint64_t lastUpdate = 0;
     uint64_t newLastUpdate = lastUpdate;
     auto sparseAr = env->GetObjectField(thiz, gmData);
-    if (sparseAr == NULL) return false;
+    if (sparseAr == nullptr) return false;
     auto data = android::bpf::getUidsUpdatedConcurrentTimes(&newLastUpdate);
     if (!data.has_value()) return false;
 
@@ -134,7 +134,7 @@ static jboolean KernelCpuUidClusterTimeBpfMapReader_readBpfData(JNIEnv *env, job
             for (const auto &subVec : times.policy) s += subVec.size();
         }
         jlongArray ar = getUidArray(env, sparseAr, uid, s);
-        if (ar == NULL) return false;
+        if (ar == nullptr) return false;
         copy2DVecToArray(env, ar, times.policy);
     }
     lastUpdate = newLastUpdate;
@@ -143,12 +143,12 @@ static jboolean KernelCpuUidClusterTimeBpfMapReader_readBpfData(JNIEnv *env, job
 
 static jlongArray KernelCpuUidClusterTimeBpfMapReader_getDataDimensions(JNIEnv *env, jobject) {
     auto times = android::bpf::getUidConcurrentTimes(0);
-    if (!times.has_value()) return NULL;
+    if (!times.has_value()) return nullptr;
 
     std::vector<jlong> clusterCores;
     for (const auto &vec : times->policy) clusterCores.push_back(vec.size());
     auto ar = env->NewLongArray(clusterCores.size());
-    if (ar != NULL) env->SetLongArrayRegion(ar, 0, clusterCores.size(), clusterCores.data());
+    if (ar != nullptr) env->SetLongArrayRegion(ar, 0, clusterCores.size(), clusterCores.data());
     return ar;
 }