ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/package/system/zram-swap/files/zram.init b/package/system/zram-swap/files/zram.init
new file mode 100755
index 0000000..35ee60c
--- /dev/null
+++ b/package/system/zram-swap/files/zram.init
@@ -0,0 +1,196 @@
+#!/bin/sh /etc/rc.common
+
+START=11
+
+extra_command "compact" "Trigger compaction for all zram swap devices"
+extra_command "status" "Print out information & statistics about zram swap devices"
+
+ram_getsize()
+{
+ local line
+
+ while read line; do case "$line" in MemTotal:*) set $line; echo "$2"; break ;; esac; done </proc/meminfo
+}
+
+zram_getsize() # in megabytes
+{
+ local zram_size="$( uci -q get system.@system[0].zram_size_mb )"
+ local ram_size="$( ram_getsize )"
+
+ if [ -z "$zram_size" ]; then
+ # e.g. 6MB for 32MB-routers or 20MB for 96MB-routers
+ echo $(( ram_size / 4096 ))
+ else
+ echo "$zram_size"
+ fi
+}
+
+zram_dev()
+{
+ local idx="$1"
+ echo "/dev/zram${idx:-0}"
+}
+
+zram_reset()
+{
+ local dev="$1"
+ local message="$2"
+ local proc_entry="/sys/block/$( basename "$dev" )/reset"
+
+ logger -s -t zram_reset -p daemon.debug "$message via $proc_entry"
+ echo "1" >"$proc_entry"
+}
+
+zram_getdev()
+{
+ #get unallocated zram dev
+ local zdev=$( zram_dev )
+
+ if [ "$(mount | grep $zdev)" ]; then
+ local idx=$(cat /sys/class/zram-control/hot_add)
+ zdev="$( zram_dev $idx )"
+ fi
+
+ echo $zdev
+}
+
+zram_comp_algo()
+{
+ local dev="$1"
+ local zram_comp_algo="$( uci -q get system.@system[0].zram_comp_algo )"
+
+ if [ -z "$zram_comp_algo" ]; then
+ # default to lzo, which is always available
+ zram_comp_algo="lzo"
+ fi
+
+ if [ $(grep -c "$zram_comp_algo" /sys/block/$( basename $dev )/comp_algorithm) -ne 0 ]; then
+ logger -s -t zram_comp_algo -p daemon.debug "set compression algorithm '$zram_comp_algo' for zram '$dev'"
+ echo $zram_comp_algo > "/sys/block/$( basename $dev )/comp_algorithm"
+ else
+ logger -s -t zram_comp_algo -p daemon.debug "compression algorithm '$zram_comp_algo' is not supported for '$dev'"
+ fi
+}
+
+#print various stats info about zram swap device
+zram_stats()
+{
+ local zdev="/sys/block/$( basename "$1" )"
+
+ printf "\nGathering stats info for zram device \"$( basename "$1" )\"\n\n"
+
+ printf "ZRAM\n----\n"
+ printf "%-25s - %s\n" "Block device" $zdev
+ awk '{ printf "%-25s - %d MiB\n", "Device size", $1/1024/1024 }' <$zdev/disksize
+ printf "%-25s - %s\n" "Compression algo" "$(cat $zdev/comp_algorithm)"
+
+ awk 'BEGIN { fmt = "%-25s - %.2f %s\n"
+ fmt2 = "%-25s - %d\n"
+ print "\nDATA\n----" }
+ { printf fmt, "Original data size", $1/1024/1024, "MiB"
+ printf fmt, "Compressed data size", $2/1024/1024, "MiB"
+ printf fmt, "Compress ratio", $1/$2, ""
+ print "\nMEMORY\n------"
+ printf fmt, "Memory used, total", $3/1024/1024, "MiB"
+ printf fmt, "Allocator overhead", ($3-$2)/1024/1024, "MiB"
+ printf fmt, "Allocator efficiency", $2/$3*100, "%"
+ printf fmt, "Maximum memory ever used", $5/1024/1024, "MiB"
+ printf fmt, "Memory limit", $4/1024/1024, "MiB"
+ print "\nPAGES\n-----"
+ printf fmt2, "Same pages count", $6
+ printf fmt2, "Pages compacted", $7 }' <$zdev/mm_stat
+
+ awk '{ printf "%-25s - %d\n", "Free pages discarded", $4 }' <$zdev/io_stat
+}
+
+zram_compact()
+{
+ # compact zram device (reduce memory allocation overhead)
+ local zdev="/sys/block/$( basename "$1" )"
+
+ local old_mem_used=$(awk '{print $3}' <$zdev/mm_stat)
+ local old_overhead=$(awk '{print $3-$2}' <$zdev/mm_stat)
+
+ echo 1 > $zdev/compact
+
+ # If not running interactively, than just return
+ [ -z "$PS1" ] && return 0
+
+ echo ""
+ echo "Compacting zram device $zdev"
+ awk -v old_mem="$old_mem_used" -v ovr="$old_overhead" 'BEGIN { fmt = "%-25s - %.1f %s\n" }
+ { printf fmt, "Memory usage reduced by ", (old_mem-$3)/1024/1024, "MiB"
+ printf fmt, "Overhead reduced by", (ovr-($3-$2))/ovr*100, "%" }' <$zdev/mm_stat
+}
+
+start()
+{
+ [ -e /proc/swaps ] || {
+ logger -s -t zram_start -p daemon.crit "kernel doesn't support swap"
+ return 1
+ }
+
+ if [ $( grep -cs zram /proc/swaps ) -ne 0 ]; then
+ logger -s -t zram_start -p daemon.notice "zram swap is already mounted"
+ return 1
+ fi
+
+ local zram_dev="$( zram_getdev )"
+
+ [ -e "$zram_dev" ] || {
+ logger -s -t zram_start -p daemon.crit "[ERROR] device '$zram_dev' not found"
+ return 1
+ }
+
+ local zram_size="$( zram_getsize )"
+ local zram_priority="$( uci -q get system.@system[0].zram_priority )"
+
+ if [ -z "$zram_priority" ]; then
+ zram_priority="100"
+ fi
+
+ logger -s -t zram_start -p daemon.debug "activating '$zram_dev' for swapping ($zram_size MiB)"
+
+ zram_reset "$zram_dev" "enforcing defaults"
+ zram_comp_algo "$zram_dev"
+ echo $(( $zram_size * 1024 * 1024 )) >"/sys/block/$( basename "$zram_dev" )/disksize"
+ busybox mkswap "$zram_dev"
+ busybox swapon -d -p $zram_priority "$zram_dev"
+ # kernel defaults to '60', the lower the less it swaps out - 0 = only swap to avoid OOM
+ if [ $( ram_size ) -gt 65536 ]; then
+ echo 60 >'/proc/sys/vm/swappiness'
+ else
+ echo 90 >'/proc/sys/vm/swappiness'
+ fi
+}
+
+stop()
+{
+ local zram_dev
+
+ for zram_dev in $( grep zram /proc/swaps |awk '{print $1}' ); do {
+ logger -s -t zram_stop -p daemon.debug "deactivate swap $zram_dev"
+ busybox swapoff "$zram_dev" && zram_reset "$zram_dev" "claiming memory back"
+ local dev_index="$( echo $zram_dev | grep -o "[0-9]*$" )"
+ if [ $dev_index -ne 0 ]; then
+ logger -s -t zram_stop -p daemon.debug "removing zram $zram_dev"
+ echo $dev_index > /sys/class/zram-control/hot_remove
+ fi
+ } done
+}
+
+# show memory stats for all zram swaps
+status()
+{
+ for zram_dev in $( grep zram /proc/swaps |awk '{print $1}' ); do {
+ zram_stats "$zram_dev"
+ } done
+}
+
+# trigger compaction for all zram swaps
+compact()
+{
+ for zram_dev in $( grep zram /proc/swaps |awk '{print $1}' ); do {
+ zram_compact "$zram_dev"
+ } done
+}