Add BPF helper function for system server
Add the map iterate and stats reading helper function used by system
server into libbpf. The methods are used by both NetworkStatsService and
NetworkStatsFactory JNI library.
Delete the function that scan through cookieTagMap and delete the stats
entry that belongs to a not existing tag. This function is handed over
to system server since system server can hold a lock to prevent
processes to access bpf maps when deleting the map entries.
Bug: 30950746
Test: run cts -m CtsNetTestCases -t android.net.cts.TrafficStatsTest
Change-Id: Ie08c817d709f0ea32405989816bd6a016ebc6bf1
diff --git a/server/TrafficController.cpp b/server/TrafficController.cpp
index 3398c0a..4cfae36 100644
--- a/server/TrafficController.cpp
+++ b/server/TrafficController.cpp
@@ -127,27 +127,8 @@
}
Status TrafficController::start() {
- int ret;
- struct utsname buf;
- int kernel_version_major;
- int kernel_version_minor;
-
- ret = uname(&buf);
- if (ret) {
- return statusFromErrno(errno, "Get system information failed");
- }
-
- char dummy;
- ret = sscanf(buf.release, "%d.%d%c", &kernel_version_major, &kernel_version_minor, &dummy);
- if (ret >= 2 &&
- ((kernel_version_major == 4 && kernel_version_minor >= 9) || (kernel_version_major > 4))) {
- // Turn off the eBPF feature temporarily since the selinux rules and kernel changes are not
- // landed yet.
- // TODO: turn back on when all the other dependencies are ready.
- ebpfSupported = false;
- return netdutils::status::ok;
- } else {
- ebpfSupported = false;
+ ebpfSupported = hasBpfSupport();
+ if (!ebpfSupported) {
return netdutils::status::ok;
}
@@ -173,7 +154,7 @@
// net_bw_acct does not grant all process in that group the permission to access bpf maps. They
// still need correct sepolicy to read/write the map. And only system_server and netd have that
// permission for now.
- ret = chown(COOKIE_UID_MAP_PATH, AID_ROOT, AID_NET_BW_ACCT);
+ int ret = chown(COOKIE_UID_MAP_PATH, AID_ROOT, AID_NET_BW_ACCT);
if (ret) {
return statusFromErrno(errno, "change cookieTagMap group failed.");
}
@@ -192,8 +173,8 @@
}
ASSIGN_OR_RETURN(mUidStatsMap,
- setUpBPFMap(sizeof(struct StatsKey), sizeof(struct Stats), UID_STATS_MAP_SIZE,
- UID_STATS_MAP_PATH, BPF_MAP_TYPE_HASH));
+ setUpBPFMap(sizeof(struct StatsKey), sizeof(struct StatsValue),
+ UID_STATS_MAP_SIZE, UID_STATS_MAP_PATH, BPF_MAP_TYPE_HASH));
// Change the file mode of pinned map so both netd and system server can get the map fd
// from it.
ret = chown(UID_STATS_MAP_PATH, AID_ROOT, AID_NET_BW_ACCT);
@@ -206,8 +187,8 @@
}
ASSIGN_OR_RETURN(mTagStatsMap,
- setUpBPFMap(sizeof(struct StatsKey), sizeof(struct Stats), TAG_STATS_MAP_SIZE,
- TAG_STATS_MAP_PATH, BPF_MAP_TYPE_HASH));
+ setUpBPFMap(sizeof(struct StatsKey), sizeof(struct StatsValue),
+ TAG_STATS_MAP_SIZE, TAG_STATS_MAP_PATH, BPF_MAP_TYPE_HASH));
// Change the file mode of pinned map so both netd and system server can get the map fd
// from the path.
ret = chown(TAG_STATS_MAP_PATH, AID_ROOT, AID_NET_BW_STATS);
@@ -358,7 +339,7 @@
// set to the nonexist_statskey because it will never be in the map, and thus getNextMapKey will
// return 0 and set nextKey to the first key in the map.
struct StatsKey curKey, nextKey;
- curKey = NONEXIST_STATSKEY;
+ curKey = android::bpf::NONEXISTENT_STATSKEY;
while (getNextMapKey(mTagStatsMap, &curKey, &nextKey) != -1) {
if (nextKey.uid == uid && (nextKey.tag == tag || tag == 0)) {
res = deleteMapEntry(mTagStatsMap, &nextKey);
@@ -386,16 +367,16 @@
// removed uid entry. The removed uid is stored in uid 0, tag 0 and
// counterSet as COUNTERSETS_LIMIT.
StatsKey removedStatsKey = {0, 0, COUNTERSETS_LIMIT, 0};
- Stats removedStatsTotal = {};
+ StatsValue removedStatsTotal = {};
res = findMapEntry(mUidStatsMap, &removedStatsKey, &removedStatsTotal);
if (res < 0 && errno != ENOENT) {
ALOGE("Failed to get stats of removed uid: %s", strerror(errno));
}
- curKey = NONEXIST_STATSKEY;
+ curKey = android::bpf::NONEXISTENT_STATSKEY;
while (getNextMapKey(mUidStatsMap, &curKey, &nextKey) != -1) {
if (nextKey.uid == uid) {
- Stats old_stats = {};
+ StatsValue old_stats = {};
res = findMapEntry(mUidStatsMap, &nextKey, &old_stats);
if (res < 0) {
if (errno != ENOENT) {