#!/bin/bash
# SPDX-License-Identifier: BSD-3-Clause
# Copyright (c) 2026 Open-IOV contributors
# pin_miss_pages.sh - adaptive tracker-sem pinner.
#
# Watches the host journal for "release miss va=0x..." lines, resolves those
# pages for the *live* cdt pid via the guest's pagemap (pmapall.py) and injects
# the translation with sema_map_add (which also rewinds the pump by 8 entries,
# so releases already consumed under a stale pin are re-read). Re-pins when a
# new cdt pid appears: pins are per-process pages and survive across cdt runs,
# which is exactly the stale-pin poisoning the rewind fixes - but the *new*
# process's pages must still be injected.
#
# Usage: tools/guest-diag/pin_miss_pages.sh [minutes]   (default 30)
set -u
cd "$(dirname "$(readlink -f "$0")")/../.."
EXEC() { timeout 40 ./scripts/vgpu_vm.py exec --timeout 35 "$1" 2>/dev/null; }

B64=$(base64 -w0 tools/guest-diag/guest_pmap_all.py)
EXEC "echo '$B64' | base64 -d > /tmp/pmapall.py" >/dev/null

MAXMIN=${1:-30}
START=$(date '+%Y-%m-%d %H:%M:%S')
seen=""
last_pid=""

for ((i = 1; i <= MAXMIN * 4; i++)); do
    sleep 15
    pid=$(EXEC 'pgrep -x cdt | head -1' | tail -1)
    if [ -z "$pid" ]; then
        echo "[$((i * 15))s] no cdt"
        continue
    fi
    if [ "$pid" != "$last_pid" ]; then
        seen=""
        last_pid="$pid"
        echo "[$((i * 15))s] new cdt pid $pid"
    fi
    vas=$(sudo journalctl -k --since "$START" --no-pager 2>/dev/null |
        grep -aoE 'release miss va=0x[0-9a-f]+' | grep -oE '0x[0-9a-f]+$' | sort -u)
    vas=$(printf '%s\n0x20400f000\n' "$vas" | sort -u)
    for va in $vas; do
        page=$(printf '0x%x' $((va & -4096)))
        case " $seen " in
        *" $page "*) continue ;;
        esac
        line=$(EXEC "sudo python3 /tmp/pmapall.py $pid $page 1" |
            grep -aE "^$page,0x[0-9a-f]+$" | head -1)
        if [ -n "$line" ]; then
            echo "$line,0x1000,1" | sudo tee /sys/module/vgsp/parameters/sema_map_add >/dev/null
            echo "[$((i * 15))s] pinned $line (pid $pid)"
            seen="$seen $page"
        fi
    done
    st=$(EXEC 'sudo tail -1 /tmp/cdt.out' | tail -1)
    case "$st" in
    *FAILED* | *"ALL OK"*) echo "[$((i * 15))s] cdt finished: $st" ;;
    esac
done
echo "=== final cdt.out ==="
EXEC 'sudo cat /tmp/cdt.out'