diff options
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/guest-diag/guest_pin_stream.py | 62 |
1 files changed, 43 insertions, 19 deletions
diff --git a/tools/guest-diag/guest_pin_stream.py b/tools/guest-diag/guest_pin_stream.py index 169d048..bb3f99a 100644 --- a/tools/guest-diag/guest_pin_stream.py +++ b/tools/guest-diag/guest_pin_stream.py @@ -22,6 +22,8 @@ HI = int(sys.argv[4], 16) if len(sys.argv) > 4 else 0x206000000 PAMAX = int(sys.argv[5], 16) if len(sys.argv) > 5 else 0x180000000 INTERVAL = float(os.environ.get("STREAM_INTERVAL", "0.25")) BATCH = 4096 +REGION = 0x200000 +SPAN = int(os.environ.get("STREAM_SPAN", "0x10000"), 16) def cdt_pid(): @@ -38,28 +40,38 @@ def cdt_pid(): def scan(pid): - """Present pages of the VA range as {va: pa}.""" + """Present pages in the first SPAN bytes of every REGION, as {va: pa}. + + The pushes sit at the start of each per-channel allocation (2/4 MB + aligned); scanning only the allocation heads keeps the per-loop page + table work small, which is what makes the stream fast while the client + is mapping and the guest is loaded. + """ fd = os.open('/proc/%d/pagemap' % pid, os.O_RDONLY) out = {} try: - va = LO & ~0xFFF - while va < HI: - n = min(BATCH, (HI - va) // 0x1000) - if n <= 0: - break - os.lseek(fd, (va // 4096) * 8, 0) - data = os.read(fd, n * 8) - got = len(data) // 8 - for i in range(got): - e = int.from_bytes(data[i * 8:i * 8 + 8], 'little') - if not ((e >> 63) & 1): - continue - pfn = e & ((1 << 55) - 1) - pa = pfn << 12 - if not pa or (PAMAX and pa >= PAMAX): - continue - out[va + i * 0x1000] = pa - va += got * 0x1000 + base = LO & ~(REGION - 1) + while base < HI: + va = max(base, LO) & ~0xFFF + end = min(base + SPAN, HI) + while va < end: + n = min(BATCH, (end - va) // 0x1000) + if n <= 0: + break + os.lseek(fd, (va // 4096) * 8, 0) + data = os.read(fd, n * 8) + got = len(data) // 8 + for i in range(got): + e = int.from_bytes(data[i * 8:i * 8 + 8], 'little') + if not ((e >> 63) & 1): + continue + pfn = e & ((1 << 55) - 1) + pa = pfn << 12 + if not pa or (PAMAX and pa >= PAMAX): + continue + out[va + i * 0x1000] = pa + va += got * 0x1000 + base += REGION finally: os.close(fd) return out @@ -71,6 +83,7 @@ def main(): sock = None seen = {} last_pid = None + last_log = 0.0 while True: pid = cdt_pid() if pid is None: @@ -87,13 +100,24 @@ def main(): except OSError: sock.close() sock = None + t0 = time.time() try: cur = scan(pid) except OSError: time.sleep(INTERVAL) continue + dt = time.time() - t0 new = [(va, pa) for va, pa in cur.items() if seen.get(va) != pa] seen = cur + now = time.time() + if now - last_log > 1.0: + last_log = now + try: + with open('/tmp/guest_pin_stream.log', 'a') as f: + f.write('%s pid=%s present=%d new=%d scan=%.3fs\n' + % (time.strftime('%T'), pid, len(cur), len(new), dt)) + except OSError: + pass if not new: time.sleep(INTERVAL) continue |