From bb267fa16f8a1a13283575a4e89b880cd44a00b2 Mon Sep 17 00:00:00 2001
From: Mark Salyzyn <salyzyn@google.com>
Date: Thu, 14 Dec 2017 12:23:05 -0800
Subject: [PATCH] STOPSHIP: sys.vdso reflector for experiments

On userdebug or eng, permit vdso to be enabled or disabled at will to
manage performance experiments on the dogfood population.

ro.debuggable=1 -> permit sys.vdso to maintain an influence over vdso
sys.vdso=false  -> 32 and 64 bit vdso disabled
sys.vdso=32     -> 64 bit vdso disabled
sys.vdso=64     -> 32 bit vdso disabled
sys.vdso=       -> 32 and 64 bit vdso enabled

NB: sys.vdso set to any other value will default to vdso enabled.

Test: manual, bionic-benchmarks --bionic_xml=vdso.xml to confirm.
Bug: 70518189
Change-Id: I839feff206a1404f228a5bdf35fb0c392fd8974a
---
 init.hardware.diag.rc.userdebug | 15 +++++++++++++++
 sepolicy/vendor/file.te         |  2 ++
 sepolicy/vendor/file_contexts   |  3 +++
 sepolicy/vendor/init.te         |  5 +++++
 4 files changed, 25 insertions(+)

diff --git a/init.hardware.diag.rc.userdebug b/init.hardware.diag.rc.userdebug
index c0536379..0366ee48 100644
--- a/init.hardware.diag.rc.userdebug
+++ b/init.hardware.diag.rc.userdebug
@@ -401,3 +401,18 @@ on property:persist.bluetooth.btsnoopenable=true
 
 on property:persist.bluetooth.btsnoopenable=false
    setprop persist.service.bdroid.soclog false
+
+# b/70518189 vDSO experiments
+on property:sys.vdso=*
+   write /sys/module/vdso/parameters/enable_32 1
+   write /sys/module/vdso/parameters/enable_64 1
+
+on property:sys.vdso=false
+   write /sys/module/vdso/parameters/enable_32 0
+   write /sys/module/vdso/parameters/enable_64 0
+
+on property:sys.vdso=64
+   write /sys/module/vdso/parameters/enable_32 0
+
+on property:sys.vdso=32
+   write /sys/module/vdso/parameters/enable_64 0
diff --git a/sepolicy/vendor/file.te b/sepolicy/vendor/file.te
index 118fbd16..f503f7a5 100644
--- a/sepolicy/vendor/file.te
+++ b/sepolicy/vendor/file.te
@@ -15,6 +15,8 @@ type sysfs_timestamp_switch, sysfs_type, fs_type;
 type sysfs_touch, sysfs_type, fs_type;
 type sysfs_usb_c, sysfs_type, fs_type;
 type sysfs_usb_device, sysfs_type, fs_type;
+# b/70518189 vDSO experiments
+type sysfs_vdso, fs_type, sysfs_type;
 
 type debugfs_clk, debugfs_type, fs_type;
 type debugfs_ion, debugfs_type, fs_type;
diff --git a/sepolicy/vendor/file_contexts b/sepolicy/vendor/file_contexts
index 11839321..26078d08 100644
--- a/sepolicy/vendor/file_contexts
+++ b/sepolicy/vendor/file_contexts
@@ -282,3 +282,6 @@
 
 /metadata                 u:object_r:rootfs:s0
 /metadata/.*              u:object_r:vold_data_file:s0
+
+# b/70518189 vDSO experiments
+/sys/module/vdso/parameters  u:object_r:sysfs_vdso:s0
diff --git a/sepolicy/vendor/init.te b/sepolicy/vendor/init.te
index fe41cf49..5a8db16a 100644
--- a/sepolicy/vendor/init.te
+++ b/sepolicy/vendor/init.te
@@ -15,3 +15,8 @@ allow init boot_block_device:lnk_file relabelto;
 allow init persist_block_device:lnk_file relabelto;
 
 dontaudit init kernel:system module_request;
+
+# b/70518189 vDSO experiments
+userdebug_or_eng(`
+allow init sysfs_vdso:file w_file_perms;
+')