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Mon, 17 Aug 2026 23:11:17 -0700 (PDT) From: Kunwu Chan X-Google-Original-From: Kunwu Chan To: sj@kernel.org, akpm@linux-foundation.org Cc: damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, rostedt@goodmis.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, shuah@kernel.org, lianux.mm@gmail.com, Kunwu Chan Subject: [RFC PATCH 5/7] selftests/damon: add automated layer-by-layer observability test Date: Tue, 18 Aug 2026 14:10:29 +0800 Message-ID: <20260818061031.827057-6-kunwu.chan@linux.dev> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260818061031.827057-1-kunwu.chan@linux.dev> References: <20260818061031.827057-1-kunwu.chan@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Kunwu Chan Drive the observe framework end-to-end with a software page-fault PMU positive control (no hardware PMU required): create a kdamond with a perf event via the DAMON sysfs interface, run a memory-pressure workload, capture a bounded trace window, and assert each pipeline layer from per-run snapshot/delta counter deltas (counters are cumulative since boot, so the snapshot is taken before the workload window): callbacks, valid data addresses, ring enqueue/dequeue/ overflow, drain match/update, the four DAMON perf tracepoints, and the per-CPU state column advancing CREATED/BOUND/ENABLED to RUNNING after the first callback. A clean-session guard refuses to run while a kdamond already exists. Ends with a PMU support verdict (FULLY INTEGRATED / PLUMBING-ONLY / UNUSABLE). Cleanup is ownership safe: it tears down only the kdamond, workload and debugfs mount created by this invocation, and retains the raw evidence directory by default. Co-developed-by: Lian Wang Signed-off-by: Lian Wang Signed-off-by: Kunwu Chan --- tools/testing/selftests/damon/Makefile | 1 + .../selftests/damon/damon_perf_obs_test.sh | 562 ++++++++++++++++++ 2 files changed, 563 insertions(+) create mode 100755 tools/testing/selftests/damon/damon_perf_obs_test.sh diff --git a/tools/testing/selftests/damon/Makefile b/tools/testing/selftests/damon/Makefile index 2180c328a825..1db8fa95ba2d 100644 --- a/tools/testing/selftests/damon/Makefile +++ b/tools/testing/selftests/damon/Makefile @@ -23,4 +23,5 @@ TEST_PROGS += sysfs_no_op_commit_break.py EXTRA_CLEAN = __pycache__ +TEST_PROGS += damon_perf_obs_test.sh include ../lib.mk diff --git a/tools/testing/selftests/damon/damon_perf_obs_test.sh b/tools/testing/selftests/damon/damon_perf_obs_test.sh new file mode 100755 index 000000000000..4c4074cdd191 --- /dev/null +++ b/tools/testing/selftests/damon/damon_perf_obs_test.sh @@ -0,0 +1,562 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# +# DAMON Perf Observability Framework — Automated Layer-by-Layer Test +# +# Validates all 7 pipeline stages: +# Layer 1: Event Create Layer 2: Event Bind +# Layer 3: Event Enable Layer 4: Sampling (callback) +# Layer 5: Ring Layer 6: Drain +# Layer 7: Match & Update +# +# The framework counters are cumulative since boot, so this script +# snapshots them before the workload and reports per-run deltas. It +# also clears the trace buffer before the sampling window so trace.txt +# carries only records produced by this run. +# +# Usage: +# # Software page-fault positive control (exercises the FULL pipeline, +# # works on any machine, no HW PMU required). Defaults to sampling +# # every page fault (period 1); override with --freq/--period: +# sudo ./damon_perf_obs_test.sh --pmu software +# sudo ./damon_perf_obs_test.sh --pmu software --freq 1 --sample-freq 100 +# +# # With ARM SPE: +# sudo ./damon_perf_obs_test.sh --pmu arm_spe_0 --freq 0 --period 256 +# +# # With any PMU type number: +# sudo ./damon_perf_obs_test.sh --pmu-type 38 --freq 0 --period 256 +# +# Notes: +# - `--config N` sets perf_event_attr.config. For PERF_TYPE_SOFTWARE, +# config 2 (PERF_COUNT_SW_PAGE_FAULTS) is the only software event +# that populates data->addr; cpu-clock (config 0) delivers callbacks +# with addr always 0, so it can only validate Layers 1-4. +# - ARM SPE cannot sample through perf_event_create_kernel_counter() +# (it requires an AUX ring buffer, see arm_spe_pmu.c), so an SPE run +# is expected to report zero callbacks until an AUX backend exists. +# A zero-callback delta is the correct "PMU not usable" verdict. +# +# Requirements: +# - CONFIG_DAMON_PERF_OBSERVE=y (fatal if missing) +# - Root privileges +# - debugfs mounted + +set -e + +# ---- defaults ---- +PMU_NAME="" +PMU_TYPE="" +PMU_CONFIG=0 +CONFIG_EXPLICIT=0 +FREQ=0 +PERIOD=256 +FREQ_EXPLICIT=0 +PERIOD_EXPLICIT=0 +SAMPLE_FREQ=100 +TIMEOUT=10 +TRACE_WINDOW=3 +TARGET_PID="" +RESULTS_DIR="/tmp/damon_perf_test_$$" +PASSED=0 +FAILED=0 +SKIPPED=0 +STRESS_PID="" +CREATED_KDAMOND=0 +MOUNTED_DEBUGFS=0 +KEEP_RESULTS=${KEEP_RESULTS:-1} + +# ---- helpers ---- +pass() { echo " [PASS] $1"; PASSED=$((PASSED + 1)); } +fail() { echo " [FAIL] $1 — $2"; FAILED=$((FAILED + 1)); } +skip() { echo " [SKIP] $1 — $2"; SKIPPED=$((SKIPPED + 1)); } +die() { echo "FATAL: $1"; exit 1; } + +# ---- sysfs roots (kept under 100 columns) ---- +KD=/sys/kernel/mm/damon/admin/kdamonds +ADMIN=$KD/0 +TRACE=/sys/kernel/debug/tracing +TPD=$TRACE/events/damon +PE=$ADMIN/contexts/0/monitoring_attrs/sample/perf_events + +# ---- saved pre-test state (restored in cleanup so the test is +# ---- side-effect free: tracepoints, tracing_on) +ORIG_TRACING_ON=$(cat $TRACE/tracing_on 2>/dev/null || echo 0) +ORIG_TP_SAMPLE=$(cat $TRACE/events/damon/damon_perf_sample/enable 2>/dev/null || echo 0) +ORIG_TP_OVERFLOW=$(cat $TRACE/events/damon/damon_perf_ring_overflow/enable 2>/dev/null || echo 0) +ORIG_TP_MISSED=$(cat $TRACE/events/damon/damon_perf_report_missed/enable 2>/dev/null || echo 0) +ORIG_TP_DRAIN=$(cat $TRACE/events/damon/damon_perf_drain/enable 2>/dev/null || echo 0) + +cleanup() { + echo "" + echo "=== Cleaning up ===" + if [[ -n "$STRESS_PID" ]]; then + kill "$STRESS_PID" 2>/dev/null || true + wait "$STRESS_PID" 2>/dev/null || true + STRESS_PID="" + fi + # Tear down only the kdamond instance created by this test. In + # particular, the early "existing kdamonds" guard must be read-only. + if [[ "$CREATED_KDAMOND" == "1" ]]; then + echo off > $ADMIN/state 2>/dev/null || true + echo 0 > $KD/nr_kdamonds 2>/dev/null || true + CREATED_KDAMOND=0 + fi + # Restore tracepoint and tracing state + echo 0 > $TRACE/tracing_on 2>/dev/null || true + echo "$ORIG_TP_SAMPLE" > $TRACE/events/damon/damon_perf_sample/enable 2>/dev/null || true + echo "$ORIG_TP_OVERFLOW" > $TPD/damon_perf_ring_overflow/enable 2>/dev/null || true + echo "$ORIG_TP_MISSED" > $TPD/damon_perf_report_missed/enable 2>/dev/null || true + echo "$ORIG_TP_DRAIN" > $TRACE/events/damon/damon_perf_drain/enable 2>/dev/null || true + echo "$ORIG_TRACING_ON" > $TRACE/tracing_on 2>/dev/null || true + if [[ "$MOUNTED_DEBUGFS" == "1" ]]; then + umount /sys/kernel/debug 2>/dev/null || true + MOUNTED_DEBUGFS=0 + fi + [ "$KEEP_RESULTS" != "1" ] && rm -rf "$RESULTS_DIR" +} +trap cleanup EXIT + +# ---- argument parsing ---- +while [[ $# -gt 0 ]]; do + case "$1" in + --pmu) PMU_NAME="$2"; shift 2 ;; + --pmu-type) PMU_TYPE="$2"; shift 2 ;; + --config) PMU_CONFIG="$2"; CONFIG_EXPLICIT=1; shift 2 ;; + --freq) FREQ="$2"; FREQ_EXPLICIT=1; shift 2 ;; + --period) PERIOD="$2"; PERIOD_EXPLICIT=1; shift 2 ;; + --sample-freq) SAMPLE_FREQ="$2"; shift 2 ;; + --trace-window) TRACE_WINDOW="$2"; shift 2 ;; + --timeout) TIMEOUT="$2"; shift 2 ;; + --pid) TARGET_PID="$2"; shift 2 ;; + *) echo "Unknown: $1"; exit 1 ;; + esac +done + +# Resolve PMU type +if [[ -n "$PMU_NAME" && -z "$PMU_TYPE" ]]; then + if [[ "$PMU_NAME" == "software" ]]; then + PMU_TYPE=1 + else + PMU_TYPE=$(cat /sys/bus/event_source/devices/$PMU_NAME/type 2>/dev/null) || + die "Cannot find PMU: $PMU_NAME" + fi +fi +[[ -z "$PMU_TYPE" ]] && die "Specify --pmu or --pmu-type " + +# For PERF_TYPE_SOFTWARE default to PERF_COUNT_SW_PAGE_FAULTS (config 2): +# the only software event that carries a data address, i.e. the only one +# that can exercise Layers 5-7. Override with --config 0 for a pure +# plumbing (cpu-clock) smoke test. +if [[ "$PMU_TYPE" == "1" && "$CONFIG_EXPLICIT" == "0" ]]; then + PMU_CONFIG=2 +fi + +# For the page-fault positive control, sample every fault (period 1) by +# default so enough reports flow for the ring/drain/match checks to be +# meaningful on a short run. Explicit --freq/--period override this. +if [[ "$PMU_TYPE" == "1" && "$PMU_CONFIG" == "2" && + "$FREQ_EXPLICIT" == "0" && "$PERIOD_EXPLICIT" == "0" ]]; then + FREQ=0 + PERIOD=1 +fi + +# For cpu-clock (config 0), sample_period is a TIME in ns, so the +# default period 256 would mean 4 MHz of callbacks per CPU. Never +# let an unguarded default hit that: fall back to a gentle 100 Hz. +if [[ "$PMU_TYPE" == "1" && "$PMU_CONFIG" == "0" && + "$FREQ_EXPLICIT" == "0" && "$PERIOD_EXPLICIT" == "0" ]]; then + FREQ=1 + SAMPLE_FREQ=100 +fi + +# ---- Layer 0: Environment ---- +echo "==========================================" +echo " DAMON Perf Observability — Layer-by-Layer Test" +echo "==========================================" +echo "PMU type: $PMU_TYPE config: $PMU_CONFIG freq: $FREQ period: $PERIOD timeout: ${TIMEOUT}s" +if [[ -n "$TARGET_PID" ]]; then + echo "Target PID: $TARGET_PID (explicit)" +else + echo "Target PID: workload process (started below)" +fi +echo "" + +mkdir -p "$RESULTS_DIR" + +echo "--- Layer 0: Environment ---" + +# Check kernel config +CONFIG="" +if [[ -f /proc/config.gz ]]; then + CONFIG=$(zcat /proc/config.gz) +elif [[ -f /boot/config-$(uname -r) ]]; then + CONFIG=$(cat /boot/config-$(uname -r)) +else + die "Cannot read /proc/config.gz or /boot/config-$(uname -r)" +fi + +for opt in DAMON DAMON_SYSFS DAMON_VADDR PERF_EVENTS DEBUG_FS TRACING \ + TRACEPOINTS; do + if echo "$CONFIG" | grep -q "CONFIG_${opt}=y"; then + pass "CONFIG_${opt}=y" + else + fail "CONFIG_${opt}" "not enabled" + fi +done + +# DAMON_PERF_OBSERVE is fatal — the test cannot run without it +if echo "$CONFIG" | grep -q "CONFIG_DAMON_PERF_OBSERVE=y"; then + pass "CONFIG_DAMON_PERF_OBSERVE=y" +else + die "kernel not built with CONFIG_DAMON_PERF_OBSERVE=y" +fi + +# Check root +[[ $(id -u) -eq 0 ]] || die "Must run as root" + +# Mount debugfs only when this test owns the mount, and undo it on exit. +if ! mountpoint -q /sys/kernel/debug; then + mount -t debugfs none /sys/kernel/debug || die "Cannot mount debugfs" + MOUNTED_DEBUGFS=1 +fi +[[ -d /sys/kernel/debug/damon ]] || die "debugfs damon/ not found" +pass "debugfs mounted" + +# Check tracepoints +for tp in damon_perf_sample damon_perf_ring_overflow damon_perf_report_missed damon_perf_drain; do + if [[ -d /sys/kernel/debug/tracing/events/damon/$tp ]]; then + pass "tracepoint $tp exists" + else + fail "tracepoint $tp" "not found" + fi +done + +# Check debugfs file (perf_stats only; format is debug-only, not an ABI) +if [[ -f /sys/kernel/debug/damon/perf_stats ]]; then + pass "debugfs perf_stats exists" +else + fail "debugfs perf_stats" "not found" +fi + +# ---- Guard: refuse to run if kdamonds already exist ---- +NR_KDAMONDS=$(cat $KD/nr_kdamonds 2>/dev/null || echo 0) +if [[ "$NR_KDAMONDS" -gt 0 ]]; then + skip "runtime" "kdamonds exist (nr_kdamonds=$NR_KDAMONDS) — refusing" + KEEP_RESULTS=1 + exit 0 +fi + +# ---- Generate memory pressure workload first: the default DAMON +# ---- target must be the workload process itself, so the workload +# ---- must be running before the target PID is written. +echo "" +echo "Starting memory workload for ${TIMEOUT}s..." +if command -v stress-ng &>/dev/null; then + stress-ng --vm 2 --vm-bytes 256M --timeout "${TIMEOUT}s" & + STRESS_PID=$! +elif command -v stress &>/dev/null; then + stress --vm 2 --vm-bytes 256M --timeout "${TIMEOUT}s" & + STRESS_PID=$! +else + # Fallback: dd-based memory pressure + dd if=/dev/zero of=/dev/null bs=1M count=1024 & + STRESS_PID=$! +fi + +# Resolve target PID: explicit --pid wins, otherwise the workload +if [[ -z "$TARGET_PID" ]]; then + TARGET_PID=$STRESS_PID +fi + +echo "" +echo "--- Layer 1: Event Create ---" + +# Configure kdamond +echo 1 > /sys/kernel/mm/damon/admin/kdamonds/nr_kdamonds +CREATED_KDAMOND=1 +echo 1 > /sys/kernel/mm/damon/admin/kdamonds/0/contexts/nr_contexts +echo 1 > /sys/kernel/mm/damon/admin/kdamonds/0/contexts/0/targets/nr_targets +echo "$TARGET_PID" > /sys/kernel/mm/damon/admin/kdamonds/0/contexts/0/targets/0/pid_target + +# Disable page-fault-based access check +echo 0 > $PE/nr_perf_events 2>/dev/null || true + +# Configure perf event +echo 1 > $PE/nr_perf_events +echo "$PMU_TYPE" > $PE/0/type +echo "$PMU_CONFIG" > $PE/0/config + +if [[ "$FREQ" -eq 1 ]]; then + echo "$SAMPLE_FREQ" > $PE/0/sample_freq +else + echo "$PERIOD" > $PE/0/sample_period +fi +echo "$FREQ" > $PE/0/freq + +# Take a dmesg snapshot before enabling the kdamond, so we can +# detect error messages that appear during the test. +DMESG_BEFORE="$RESULTS_DIR/dmesg_before.txt" +dmesg > "$DMESG_BEFORE" 2>/dev/null || true +# Snapshot counters BEFORE the workload window. All counters are +# cumulative since boot; every Analysis number below is a delta against +# this snapshot. Read before echo on so the window starts at zero. +STATS_BASE="$RESULTS_DIR/perf_stats_base.txt" +cat /sys/kernel/debug/damon/perf_stats > "$STATS_BASE" 2>/dev/null || true + +echo on > /sys/kernel/mm/damon/admin/kdamonds/0/state +sleep 2 + +DMESG_OUT="$RESULTS_DIR/dmesg_create.txt" +DMESG_DELTA="$RESULTS_DIR/dmesg_delta.txt" +dmesg > "$DMESG_OUT" 2>/dev/null || true +# Delta: lines in $DMESG_OUT not already present in $DMESG_BEFORE +awk 'NR==FNR { seen[$0]++ } + NR>FNR { if (seen[$0] > 0) seen[$0]--; else print }' \ + "$DMESG_BEFORE" "$DMESG_OUT" > "$DMESG_DELTA" || true + +# Check state is on +STATE_VAL=$(cat /sys/kernel/mm/damon/admin/kdamonds/0/state 2>/dev/null) +if [[ "$STATE_VAL" == "on" ]]; then + pass "Kdamond state is on" +else + fail "Kdamond state" "expected 'on', got '$STATE_VAL'" +fi + +echo "" +echo "--- Layer 2-3: Enable & Run (via per-CPU state) ---" + +# Parse the maximum per-CPU state from the debugfs output. +# The per-CPU line format is: +# CPU%02d: st= cb=... enq=... ... +max_cpu_state() { + awk -F'st=' '/^ CPU/ { + split($2, a, " ") + s = a[1] + # Map state name to numeric rank + if (s == "ERROR") v = 5 + else if (s == "RUNNING") v = 4 + else if (s == "ENABLED") v = 3 + else if (s == "BOUND") v = 2 + else if (s == "CREATED") v = 1 + else v = 0 + if (v > max) max = v + } END { print max+0 }' "$1" 2>/dev/null +} + +CPU_ST_BASE=$(max_cpu_state "$STATS_BASE") + +if [[ "$CPU_ST_BASE" -ge 1 ]]; then + pass "Event Created (max per-CPU state >= CREATED)" +else + fail "Event Created" "max per-CPU state is $CPU_ST_BASE" +fi + +if [[ "$CPU_ST_BASE" -ge 2 ]]; then + pass "Event Bound (max per-CPU state >= BOUND)" +else + fail "Event Bound" "max per-CPU state is $CPU_ST_BASE" +fi + +if [[ "$CPU_ST_BASE" -ge 3 ]]; then + pass "Event Enabled (max per-CPU state >= ENABLED)" +else + fail "Event Enabled" "max per-CPU state is $CPU_ST_BASE" +fi + +# Check dmesg delta for errors (vaddr.c pr_warn_ratelimited paths) +if grep -q 'damon-perf.*failed\|event create failed' "$DMESG_DELTA" 2>/dev/null; then + fail "Perf event" "perf event creation failed (see dmesg delta)" +else + pass "Perf event creation (no errors in dmesg delta)" +fi + +echo "" +echo "--- Layer 4: Sampling (Callback) ---" + +# Clear the trace buffer so trace.txt only contains records produced by +# this run, then enable tracepoints for a bounded sampling window. +echo 0 > $TRACE/tracing_on 2>/dev/null || true +echo > $TRACE/trace 2>/dev/null || true +echo 1 > $TRACE/events/damon/damon_perf_sample/enable +echo 1 > $TRACE/events/damon/damon_perf_ring_overflow/enable +echo 1 > $TRACE/events/damon/damon_perf_report_missed/enable +echo 1 > $TRACE/events/damon/damon_perf_drain/enable +echo 1 > $TRACE/tracing_on + +# Sampling window: keeps trace.txt bounded even on PMUs that sample at +# tens of kHz. Counters keep accumulating for the full TIMEOUT. +sleep "$TRACE_WINDOW" +echo 0 > $TRACE/tracing_on 2>/dev/null || true +[[ "$TIMEOUT" -gt "$TRACE_WINDOW" ]] && sleep $((TIMEOUT - TRACE_WINDOW)) + +kill $STRESS_PID 2>/dev/null || true +wait $STRESS_PID 2>/dev/null || true +STRESS_PID="" +echo "Workload done." + +sleep 2 # let kdamond drain + +# Collect trace +TRACE_OUT="$RESULTS_DIR/trace.txt" +cat /sys/kernel/debug/tracing/trace > "$TRACE_OUT" 2>/dev/null || true +TRACE_LINES=$(wc -l < "$TRACE_OUT" 2>/dev/null || echo 0) + +# Collect stats (re-read after workload) +STATS_OUT="$RESULTS_DIR/perf_stats.txt" +cat /sys/kernel/debug/damon/perf_stats > "$STATS_OUT" 2>/dev/null || true + +# ---- Analysis ---- +echo "" +echo "--- Analysis ---" + + +# Aggregate counter reads +stat_of() { + awk -v k="$1" '$1==k {print $2}' "$2" 2>/dev/null +} + +# Per-run delta between baseline and post-workload snapshots +delta() { + local b a + b=$(stat_of "$1" "$STATS_BASE") + a=$(stat_of "$1" "$STATS_OUT") + [[ -z "$b" ]] && b=0 + [[ -z "$a" ]] && a=0 + echo $((a-b)) +} + +CALLBACK=$(delta callback) +VALID=$(delta valid) +ADDR_ZERO=$(delta addr_zero) +KERNEL=$(delta kernel) +ENQUEUE=$(delta enqueue) +DEQUEUE=$(delta dequeue) +OVERFLOW=$(delta overflow) +MATCH=$(delta match) +UPDATE=$(delta update) + +echo " Callback delta this run: ${CALLBACK} (cumulative totals in perf_stats.txt)" + +if [[ "$CALLBACK" -gt 0 ]]; then + pass "Sampling: ${CALLBACK} callbacks received" +else + fail "Sampling" "0 callbacks — PMU is not delivering samples to DAMON" +fi + +echo " Callback breakdown (delta): valid=${VALID} addr_zero=${ADDR_ZERO} kernel=${KERNEL}" + +# Verify RUNNING state: first callback advances per-CPU state to +# RUNNING, which persists until the kdamond is stopped. +CPU_ST_FINAL=$(max_cpu_state "$STATS_OUT") +if [[ "$CALLBACK" -gt 0 && "$CPU_ST_FINAL" -ge 4 ]]; then + pass "Event Running (max per-CPU state >= RUNNING)" +elif [[ "$CALLBACK" -eq 0 ]]; then + skip "Event Running" "no callbacks — state cannot advance past ENABLED" +else + fail "Event Running" "callbacks > 0 but max state is $CPU_ST_FINAL" +fi + +echo " Ring: enqueue=${ENQUEUE} dequeue=${DEQUEUE} overflow=${OVERFLOW}" + +if [[ "$ENQUEUE" -gt 0 ]]; then + pass "Ring: enqueue > 0" + if [[ "$DEQUEUE" -gt 0 ]]; then + pass "Ring: dequeue > 0" + else + fail "Ring: dequeue" "enqueued but never dequeued" + fi +else + skip "Ring" "no enqueues (no valid samples: addr=0 or no callbacks)" +fi + +echo " Match: match=${MATCH} update=${UPDATE}" + +if [[ "$MATCH" -gt 0 ]]; then + pass "Drain & Match: ${MATCH} matched" + if [[ "$UPDATE" -gt 0 ]]; then + pass "Update: ${UPDATE} region updates" + else + fail "Update" "matched but never updated" + fi +else + skip "Match/Update" "no matches (no valid samples reached region matching)" +fi + +# Drain tracepoint: kdamond fires damon_perf_drain whenever it drained +# at least one report. The drain tracepoint is only expected when the +# ring actually produced entries. +DRAIN_COUNT=$(grep -c "damon_perf_drain" "$TRACE_OUT" 2>/dev/null || true) +DRAIN_COUNT=${DRAIN_COUNT:-0} +echo " Drain tracepoint: ${DRAIN_COUNT} records" +if [[ "$MATCH" -gt 0 ]]; then + if [[ "$DRAIN_COUNT" -gt 0 ]]; then + pass "Drain tracepoint fired (${DRAIN_COUNT} records)" + else + fail "Drain tracepoint" "matches occurred but damon_perf_drain never fired" + fi +else + skip "Drain tracepoint" "no drained reports to summarize" +fi + +# Context verification +if grep -q 'context=' "$TRACE_OUT" 2>/dev/null; then + NMI_COUNT=$(grep -c 'context=3' "$TRACE_OUT" 2>/dev/null || true) + PROC_COUNT=$(grep -c 'context=0' "$TRACE_OUT" 2>/dev/null || true) + NMI_COUNT=${NMI_COUNT:-0} + PROC_COUNT=${PROC_COUNT:-0} + echo " Context: NMI=${NMI_COUNT} process=${PROC_COUNT}" + pass "Context field in trace output" +else + skip "Context" "no trace output to analyze" +fi + +# Show a few sample records as raw evidence (they are the per-sample +# view of the pipeline; useful for PMU support evaluation). +echo "" +echo " First damon_perf_sample record(s) this run:" +if grep -q "damon_perf_sample" "$TRACE_OUT" 2>/dev/null; then + grep -m 3 "damon_perf_sample" "$TRACE_OUT" | sed 's/^/ /' +else + echo " (none — no samples captured in the ${TRACE_WINDOW}s window)" +fi +echo " First damon_perf_drain record(s) this run:" +if grep -q "damon_perf_drain" "$TRACE_OUT" 2>/dev/null; then + grep -m 3 "damon_perf_drain" "$TRACE_OUT" | sed 's/^/ /' +else + echo " (none)" +fi + +# ---- PMU support verdict ---- +echo "" +echo "--- PMU support verdict ---" +if [[ "$CALLBACK" -eq 0 ]]; then + echo " UNUSABLE: the PMU never delivered a sample to DAMON" + echo " (e.g. ARM SPE requires an AUX ring buffer that kernel" + echo " counters do not provide; see arm_spe_pmu.c)" +elif [[ "$VALID" -eq 0 ]]; then + echo " PLUMBING-ONLY: callbacks flow but no data addresses" + echo " (address-less PMU, e.g. cpu-clock / task-clock)" +elif [[ "$ENQUEUE" -gt 0 && "$MATCH" -gt 0 ]]; then + echo " FULLY INTEGRATED: samples carry addresses and reach" + echo " DAMON region matching/update" +else + echo " PARTIAL: callbacks with addresses, but the drain/match" + echo " pipeline did not complete (see counters above)" +fi + +# ---- Summary ---- +echo "" +echo "==========================================" +echo " SUMMARY: $PASSED passed, $FAILED failed, $SKIPPED skipped" +echo "==========================================" +echo "" +echo "Results retained in: $RESULTS_DIR (set KEEP_RESULTS=0 to remove)" + +if [[ "$FAILED" -gt 0 ]]; then + echo "Overall: FAIL ($FAILED checks failed)" + exit 1 +else + echo "Overall: PASS" + exit 0 +fi -- 2.43.0