Integrate page_alloc_stall.sh, a script to synchronize userspace and kernelspace workloads to reproduce page allocation stalls.
Provision a synthetic loopback zswap block device, inject the test_mempress_timer.ko module to generate atomic page allocations inside kernel timers, and execute the page_alloc_stall_pressure.py payload to induce system-wide swap activity. Signed-off-by: Jason Miu <[email protected]> --- .../testing/selftests/mm/page_alloc_stall.sh | 80 +++++++++++++++++++ 1 file changed, 80 insertions(+) create mode 100644 tools/testing/selftests/mm/page_alloc_stall.sh diff --git a/tools/testing/selftests/mm/page_alloc_stall.sh b/tools/testing/selftests/mm/page_alloc_stall.sh new file mode 100644 index 000000000000..3ece026fd680 --- /dev/null +++ b/tools/testing/selftests/mm/page_alloc_stall.sh @@ -0,0 +1,80 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# +# page_alloc_stall.sh +# +# Orchestrator script to generate concurrent userspace and kernelspace +# memory allocation pressure over a synthetic zswap backing block device +# to artificially induce systemic memory contention. +# +# Dependencies: +# - External memtoy binary (Source: https://github.com/kosaki/memtoy) +# +# Usage: +# ./page_alloc_stall.sh [hog_percent=80] [workers=64] [overcommit=2.5] \ +# [swap_gb=10%_RAM] [memtoy_path="memtoy/memtoy"] + +set -e + +SCRIPT_DIR=$(cd "$(dirname "$0")" && pwd) +PYTHON_CMD=${PYTHON_CMD:-python3} + +HOG_PERCENT=${1:-80} +NUM_WORKERS=${2:-64} +OVERCOMMIT=${3:-2.5} +TARGET_SWAP_GB=$4 +MEMTOY_PATH=${5:-"memtoy/memtoy"} + +function total_mem_gb() +{ + awk '/MemTotal/ {print int($2 / 1024 / 1024)}' /proc/meminfo +} + +function enable_zswap_file() +{ + local swap_size_gb=$1 + + fallocate -l ${swap_size_gb}G "$SCRIPT_DIR/swap.img" + + LOOP_DEV=$(losetup -f --show "$SCRIPT_DIR/swap.img") + mkswap $LOOP_DEV + swapon $LOOP_DEV + + echo 1 > /sys/module/zswap/parameters/enabled +} + +function cleanup() +{ + echo "Tearing down the test..." + if lsmod | grep -q test_mempress_timer; then + rmmod test_mempress_timer || echo "Failed to rmmod mempress_timer" + fi + + # Check if loop dev was actually created before trying to destroy it + if [ -n "$LOOP_DEV" ]; then + swapoff $LOOP_DEV 2>/dev/null || true + losetup -d $LOOP_DEV 2>/dev/null || true + fi + rm -f "$SCRIPT_DIR/swap.img" +} + +trap cleanup EXIT + +if [ -z "$TARGET_SWAP_GB" ]; then + # use 10% of the total mem for zswap file by default. + TARGET_SWAP_GB=$(($(total_mem_gb) / 10)) +fi + +enable_zswap_file $TARGET_SWAP_GB + +KROOT=$(cd "$SCRIPT_DIR/../../../.." && pwd) +KO_PATH="$KROOT/lib/test_mempress_timer.ko" + +if [ "$KO_PATH" ]; then + insmod "$KO_PATH" +else + echo "WARNING: $KO_PATH not found! Aborting the test." + exit 1 +fi + +"$PYTHON_CMD" "$SCRIPT_DIR/page_alloc_stall_pressure.py" $HOG_PERCENT $NUM_WORKERS $OVERCOMMIT $MEMTOY_PATH -- 2.55.0.691.gc56d675ccc-goog
