Sort and group network stats collected from eBPF.
Since eBPF use hash map to record stats, network stats collected
from eBPF will be out of order. And the performance of
findIndexHinted in NetworkStats would be impacted.
Furthermore, since the StatsKey contains iface index, the
network stats reported to framework would create items with the
same iface, uid, tag and set, which causes NetworkStats maps
wrong item to subtract.
Thus, the stats needs to be properly sorted and grouped before
reported.
Bug: 112226716
Bug: 119193941
Test: 1. manually reconnect vpn
2. update apps from playstore
3. atest libnetdbpf_test
4. runtest frameworks-net
5. cts-tradefed run cts -m CtsUsageStatsTestCases -t \
android.app.usage.cts.NetworkUsageStatsTest
Change-Id: I6d485a368fd8e52d21d5e894fc189ac8f0e9f502
diff --git a/libnetdbpf/BpfNetworkStats.cpp b/libnetdbpf/BpfNetworkStats.cpp
index 013e7ef..907cdea 100644
--- a/libnetdbpf/BpfNetworkStats.cpp
+++ b/libnetdbpf/BpfNetworkStats.cpp
@@ -162,6 +162,17 @@
strerror(res.code()));
return -res.code();
}
+
+ // Since eBPF use hash map to record stats, network stats collected from
+ // eBPF will be out of order. And the performance of findIndexHinted in
+ // NetworkStats will also be impacted.
+ //
+ // Furthermore, since the StatsKey contains iface index, the network stats
+ // reported to framework would create items with the same iface, uid, tag
+ // and set, which causes NetworkStats maps wrong item to subtract.
+ //
+ // Thus, the stats needs to be properly sorted and grouped before reported.
+ groupNetworkStats(lines);
return 0;
}
@@ -227,6 +238,8 @@
strerror(res.code()));
return -res.code();
}
+
+ groupNetworkStats(lines);
return 0;
}
@@ -253,5 +266,66 @@
return (uint64_t)uid << 32 | tag;
}
+void groupNetworkStats(std::vector<stats_line>* lines) {
+ if (lines->size() <= 1) return;
+ std::sort(lines->begin(), lines->end());
+
+ // Similar to std::unique(), but aggregates the duplicates rather than discarding them.
+ size_t nextOutput = 0;
+ for (size_t i = 1; i < lines->size(); i++) {
+ if (lines->at(nextOutput) == lines->at(i)) {
+ lines->at(nextOutput) += lines->at(i);
+ } else {
+ nextOutput++;
+ if (nextOutput != i) {
+ lines->at(nextOutput) = lines->at(i);
+ }
+ }
+ }
+
+ if (lines->size() != nextOutput + 1) {
+ lines->resize(nextOutput + 1);
+ }
+}
+
+// True if lhs equals to rhs, only compare iface, uid, tag and set.
+bool operator==(const stats_line& lhs, const stats_line& rhs) {
+ return ((lhs.uid == rhs.uid) && (lhs.tag == rhs.tag) && (lhs.set == rhs.set) &&
+ !strncmp(lhs.iface, rhs.iface, sizeof(lhs.iface)));
+}
+
+// True if lhs is smaller then rhs, only compare iface, uid, tag and set.
+bool operator<(const stats_line& lhs, const stats_line& rhs) {
+ int ret = strncmp(lhs.iface, rhs.iface, sizeof(lhs.iface));
+ if (ret != 0) return ret < 0;
+ if (lhs.uid < rhs.uid) return true;
+ if (lhs.uid > rhs.uid) return false;
+ if (lhs.tag < rhs.tag) return true;
+ if (lhs.tag > rhs.tag) return false;
+ if (lhs.set < rhs.set) return true;
+ if (lhs.set > rhs.set) return false;
+ return false;
+}
+
+stats_line& stats_line::operator=(const stats_line& rhs) {
+ strlcpy(iface, rhs.iface, sizeof(iface));
+ uid = rhs.uid;
+ set = rhs.set;
+ tag = rhs.tag;
+ rxPackets = rhs.rxPackets;
+ txPackets = rhs.txPackets;
+ rxBytes = rhs.rxBytes;
+ txBytes = rhs.txBytes;
+ return *this;
+}
+
+stats_line& stats_line::operator+=(const stats_line& rhs) {
+ rxPackets += rhs.rxPackets;
+ txPackets += rhs.txPackets;
+ rxBytes += rhs.rxBytes;
+ txBytes += rhs.txBytes;
+ return *this;
+}
+
} // namespace bpf
} // namespace android