diff options
Diffstat (limited to 'tools/guest-diag/guest_pin_stream.py')
| -rw-r--r-- | tools/guest-diag/guest_pin_stream.py | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/tools/guest-diag/guest_pin_stream.py b/tools/guest-diag/guest_pin_stream.py index e80751a..ce98d5b 100644 --- a/tools/guest-diag/guest_pin_stream.py +++ b/tools/guest-diag/guest_pin_stream.py @@ -266,6 +266,80 @@ def _vmalloc_pages_for(kc, va): return 0 +def _nv_vmap_areas(kc): + """nv_vm_map_pages vmalloc areas: [(lo, hi, pages)] (5 s cache). + + Every CE push-buffer rm_mem is a vmap created by nv_vm_map_pages; the + demand pinner walks these areas to find the page holding a stalled + push VA by content, without needing any kprobe event or object chain. + """ + now = time.time() + if getattr(_nv_vmap_areas, "ts", 0) > now - 5.0: + return _nv_vmap_areas.areas + areas = [] + try: + for line in open("/proc/vmallocinfo"): + if "nv_vm_map_pages" not in line: + continue + p = line.split() + if len(p) < 2: + continue + try: + lo, hi = p[0].split("-") + lo = int(lo, 16) + hi = int(hi, 16) + except ValueError: + continue + pages = (hi - lo) >> 12 + if pages > 0: + areas.append((lo, hi, pages)) + except OSError: + pass + _nv_vmap_areas.areas = areas + _nv_vmap_areas.ts = now + return areas + + +def resolve_va_by_content(kc, va, out): + """Demand pin: find the page carrying GPU VA 'va' by content match. + + The host reports the CE push-buffer VAs whose GPFIFO entries it cannot + read (dmesg 'stalled VA #N: 0x...'). The guest walks every + nv_vm_map_pages vmap area and tests the candidate leaf page at the VA's + in-window offset (plus one neighbour on either side, for the per-mem + header-page offset ambiguity) against the host's method-stream prefix + check. On a match it emits the exact pair, so the host can translate + and consume the entry - no kprobe event, no object-chain discovery, no + resolution lottery. Only the requested VA is pinned, so a wrong + candidate cannot poison other VAs. + """ + if not (PB_CE_LO <= va < PB_CE_HI): + return False + off = (va - PB_CE_LO) & 0xFFFFF + k = off >> 12 + for (lo, _hi, pages) in _nv_vmap_areas(kc): + for adj in (0, 1, -1): + idx = k + adj + if idx < 0 or idx >= pages: + continue + cpu = lo + idx * 0x1000 + d = kc.read(cpu, 64) + if not d or not any(d[:32]): + continue + if not _push_prefix_ok(d): + continue + pa = kc.va_to_pa(cpu) + if pa is None: + continue + out.append("0x%x,0x%x,1\n" % (va & ~0xFFF, pa)) + dbg("demand-va: 0x%x -> pa=0x%x (area off=%d adj=%+d)" + % (va & ~0xFFF, pa, idx, adj)) + return True + dbg("demand-va: 0x%x not found by content (%d areas)" + % (va & ~0xFFF, len(_nv_vmap_areas(kc)))) + return False + + def resolve_mem_pins(kc, mem, out, default_pages=16, va_lo=0, va_hi=0, page_off=0): """uvm_rm_mem kptr -> GPU-VA/GPA runs (direct map or page-table walk). @@ -1471,6 +1545,8 @@ def main(): last_pid = None last_log = 0.0 scrub_next = 0.0 + demand_next = 0.0 + _want_state = {"mtime": None, "done": set()} loop = 0 while True: pid = cdt_pid() @@ -1549,6 +1625,37 @@ def main(): new = [(va, pa) for va, pa in cur.items() if seen.get(va) != pa] pending_cur = cur lines = [] + # Demand pins (host -> this scanner): the host appends the CE + # push-buffer VAs of GPFIFO entries it cannot read to + # /tmp/guest_want_vas.txt (written via the guest agent by + # pin_gr_stream); resolve each by content against the + # nv_vm_map_pages areas and emit the pair. This is the + # event-independent hole filler for the stall class where the + # one-shot #sem kprobe event was lost and the object-chain + # resolver never learns the client. + if kc_ok and time.time() >= demand_next: + demand_next = time.time() + 1.0 + try: + st_d = os.stat("/tmp/guest_want_vas.txt") + if st_d.st_mtime != _want_state.get("mtime"): + with open("/tmp/guest_want_vas.txt") as fw: + wvas = [int(t, 16) for t in fw.read().split() + if t.startswith("0x")] + _want_state["mtime"] = st_d.st_mtime + for wv in wvas[-64:]: + if wv in _want_state["done"]: + continue + got = [] + try: + ok = resolve_va_by_content(kc, wv, got) + except Exception: + ok = False + got = [] + if ok and got: + lines.extend(got) + _want_state["done"].add(wv) + except OSError: + pass # PMA scrubber buffer discovery (throttled): resolve the finish/host- # semaphore word PAs and stream them for host registration. if kc_ok and time.time() >= scrub_next: |