lavender: Update ZRAM configuration from LA.UM.9.2.r1-03000-SDMxx0.0

* Otherwise zram remained disabled

- Increase ZRAM swap size.
- post_boot: Ensure SLAB_STORE_USER is disabled for zram kmem_caches
- post_boot: Set zRam disk size to 50% of RAM size.
- Set zRam disk size to 50% of RAM size for non-Go devices.
- post_boot:  update zram setting avoid 32 bit overflow
- post_boot: use 'MB' as deault unit for zram disksize setting
- post_boot: updating post_boot for <=2 GB devices

Change-Id: I73ec74c4a10f2d0c65506d73f43fe64a20ed2cc5
Signed-off-by: SparXFusion <[email protected]>

rootdir/bin/init.qcom.post_boot.sh

@@ -340,13 +340,21 @@ function configure_zram_parameters() {
     # Zram disk - 75% for Go devices.
     # For 512MB Go device, size = 384MB, set same for Non-Go.
     # For 1GB Go device, size = 768MB, set same for Non-Go.
-    # For >=2GB Non-Go devices, size = 50% of RAM size. Limit the size to 4GB.
+    # For 2GB Go device, size = 1536MB, set same for Non-Go.
+    # For >2GB Non-Go devices, size = 50% of RAM size. Limit the size to 4GB.
     # And enable lz4 zram compression for Go targets.
 
-    RamSizeGB=`echo "($MemTotal / 1048576 ) + 1" | bc`
-    zRamSizeBytes=`echo "$RamSizeGB * 1024 * 1024 * 1024 / 2" | bc`
-    if [ $zRamSizeBytes -gt 4294967296 ]; then
-        zRamSizeBytes=4294967296
+    let RamSizeGB="( $MemTotal / 1048576 ) + 1"
+    diskSizeUnit=M
+    if [ $RamSizeGB -le 2 ]; then
+        let zRamSizeMB="( $RamSizeGB * 1024 ) * 3 / 4"
+    else
+        let zRamSizeMB="( $RamSizeGB * 1024 ) / 2"
+    fi
+
+    # use MB avoid 32 bit overflow
+    if [ $zRamSizeMB -gt 4096 ]; then
+        let zRamSizeMB=4096
     fi
 
     if [ "$low_ram" == "true" ]; then
@@ -357,13 +365,17 @@ function configure_zram_parameters() {
         if [ -f /sys/block/zram0/use_dedup ]; then
             echo 1 > /sys/block/zram0/use_dedup
         fi
-        if [ $MemTotal -le 524288 ]; then
-            echo 402653184 > /sys/block/zram0/disksize
-        elif [ $MemTotal -le 1048576 ]; then
-            echo 805306368 > /sys/block/zram0/disksize
-        else
-            echo $zRamSizeBytes > /sys/block/zram0/disksize
+        echo "$zRamSizeMB""$diskSizeUnit" > /sys/block/zram0/disksize
+
+        # ZRAM may use more memory than it saves if SLAB_STORE_USER
+        # debug option is enabled.
+        if [ -e /sys/kernel/slab/zs_handle ]; then
+            echo 0 > /sys/kernel/slab/zs_handle/store_user
         fi
+        if [ -e /sys/kernel/slab/zspage ]; then
+            echo 0 > /sys/kernel/slab/zspage/store_user
+        fi
+
         mkswap /dev/block/zram0
         swapon /dev/block/zram0 -p 32758
     fi
@@ -440,11 +452,9 @@ if [ "$ProductName" == "msmnile" ] || [ "$ProductName" == "kona" ] || [ "$Produc
       echo 100 > /proc/sys/vm/swappiness
 else
     arch_type=`uname -m`
-    MemTotalStr=`cat /proc/meminfo | grep MemTotal`
-    MemTotal=${MemTotalStr:16:8}
 
     # Set parameters for 32-bit Go targets.
-    if [ $MemTotal -le 1048576 ] && [ "$low_ram" == "true" ]; then
+    if [ "$low_ram" == "true" ]; then
         # Disable KLMK, ALMK, PPR & Core Control for Go devices
         echo 0 > /sys/module/lowmemorykiller/parameters/enable_lmk
         echo 0 > /sys/module/lowmemorykiller/parameters/enable_adaptive_lmk