commit 04a2c86ba594cb02c330acfa85163d85da44c8fe
author Chenbo Feng <fengc@google.com> Wed Feb 27 19:07:39 2019 -0800
committer Lorenzo Colitti <lorenzo@google.com> Tue Apr 23 14:21:32 2019 +0000
tree e279dcc54db6c295a13049daf0d5dba842557af0
parent e98964d7d287296aeb5619c6f0e2d1f0b868dd3b

Ask netd to swap stats map before reading

To avoid protentail race problem between netd and system_server when
reading the network stats map. Always inform netd before reading the
stats and let netd to do a swap between active stats map and inactive
stats map. So the system_server can safely remove the stats after
reading.

Bug: 126620214
Test: android.app.usage.cts.NetworkUsageStatsTest
      android.net.cts.TrafficStatsTest

Change-Id: I8fa37c26bec23ffca0b29b679e72ba1189f557f1
Merged-In: I8fa37c26bec23ffca0b29b679e72ba1189f557f1
(cherry picked from commit b7a5ed712570811045cd286da72defd95628fe30)