fs_mgr: overlayfs: noatime
Should not have used relatime for overlayfs and backing storage
mounts, noatime reduces the wear and tear on the flash device.
This should prevent triggering a falure in the CtsOsTestCases that
tries to spot mounts attached to block storage from updating atime
and resulting in churn. This statement does not mean we support
performing Cts tests with devices that have deployed
'adb disable-verity' or 'adb remount'.
Post-mortem: relatime was not a 'problem' for overlayfs, copy and
paste for those flags resulted in the use of relatime
for scratch backing storage.
Test: adb-remount-test.sh
Bug: 140014856
Change-Id: Ic97b98ceacaa265094364487ea70cc99b6aee92f
diff --git a/fs_mgr/fs_mgr_overlayfs.cpp b/fs_mgr/fs_mgr_overlayfs.cpp
index d7ea81d..358c980 100644
--- a/fs_mgr/fs_mgr_overlayfs.cpp
+++ b/fs_mgr/fs_mgr_overlayfs.cpp
@@ -713,7 +713,7 @@
}
report = report + ")=";
- auto ret = mount("overlay", mount_point.c_str(), "overlay", MS_RDONLY | MS_RELATIME,
+ auto ret = mount("overlay", mount_point.c_str(), "overlay", MS_RDONLY | MS_NOATIME,
options.c_str());
if (ret) {
retval = false;
@@ -776,7 +776,7 @@
entry.fs_type = mnt_type;
if ((mnt_type == "f2fs") && !f2fs) entry.fs_type = "ext4";
if ((mnt_type == "ext4") && !ext4) entry.fs_type = "f2fs";
- entry.flags = MS_RELATIME;
+ entry.flags = MS_NOATIME;
if (readonly) {
entry.flags |= MS_RDONLY;
} else {
diff --git a/fs_mgr/tests/adb-remount-test.sh b/fs_mgr/tests/adb-remount-test.sh
index ed6d0e3..7ccaf0e 100755
--- a/fs_mgr/tests/adb-remount-test.sh
+++ b/fs_mgr/tests/adb-remount-test.sh
@@ -1190,6 +1190,11 @@
skip_unrelated_mounts |
grep " overlay ro,") ||
die "remount overlayfs missed a spot (ro)"
+ !(adb_sh grep -v noatime /proc/mounts </dev/null |
+ skip_administrative_mounts data |
+ skip_unrelated_mounts |
+ grep '.') ||
+ die "mounts are not noatime"
D=`adb_sh grep " rw," /proc/mounts </dev/null |
skip_administrative_mounts data`
if echo "${D}" | grep /dev/root >/dev/null; then