diff options
Diffstat (limited to 'tools/guest-diag/semfix_uvmt.py')
| -rwxr-xr-x | tools/guest-diag/semfix_uvmt.py | 70 |
1 files changed, 23 insertions, 47 deletions
diff --git a/tools/guest-diag/semfix_uvmt.py b/tools/guest-diag/semfix_uvmt.py index 812076e..fa3ae01 100755 --- a/tools/guest-diag/semfix_uvmt.py +++ b/tools/guest-diag/semfix_uvmt.py @@ -53,8 +53,7 @@ SKIP_PB = os.environ.get("SEMFIX_SKIP_PB", "0") == "1" # Seconds between counter-page pin attempts (the guest-agent exec blocks for # its full timeout when the client saturates the guest). COUNTER_RETRY_S = float(os.environ.get("SEMFIX_COUNTER_RETRY", "10")) -# Liveness file checked by pin_supervisor.sh (mtime must stay < 75 s; the -# supervisor grants a 120 s startup grace on top). +# Liveness file checked by pin_supervisor.sh (mtime must stay < 30 s). SEMFIX_HB_FILE = os.environ.get("SEMFIX_HEARTBEAT_FILE", "/tmp/opencode/semfix_heartbeat") # Every client pid ever observed. Module-level on purpose: the per-client @@ -240,23 +239,6 @@ def cdt_pid(): return int(pids[-1]) if pids else None -def pid_alive(pid): - """Probe /proc/<pid> in the guest before a blocking exec on it. - - A killed client's pid stays latched in the watcher state; retrying its - counter pin every COUNTER_RETRY_S ran a full 25 s agent exec per attempt - and starved the scanner (the post-kill agent hammering). Assume alive on - a failed probe so a transient agent error cannot drop a live client. - """ - try: - r = subprocess.run( - [VMEXEC, "exec", "test -d /proc/%d && echo ALIVE" % pid], - capture_output=True, text=True, timeout=15) - except Exception: - return True - return "ALIVE" in (r.stdout or "") - - def pin_counter_page(pid, pinned_pids): """Pin the client's completion-counter page from its own pagemap. @@ -300,9 +282,10 @@ def main(): last_seen_t = {} dseen = set() counter_pids = set() - counter_dead = set() counter_next_try = {} last_pid = None + pending_pid = None + pending_count = 0 # Stale-sem tracking: consecutive unreadable reads, first-unreadable time, # and the per-sem read skip deadline once a sem has failed 3 times. unread_count = {} @@ -349,6 +332,7 @@ def main(): if last_pid is None: seen_pids.add(p) last_pid = p + pending_pid = None continue if p == last_pid: seen_pids.add(p) @@ -359,13 +343,20 @@ def main(): log("semfix: pid %d seen before/backwards - no reset" % p) seen_pids.add(p) continue - # Any unseen pid above the current one is a real new client. - # Stream.poll dedupes pids against its own list, so each pid - # arrives in exactly one poll batch and never repeats - the old - # two-poll debounce therefore never fired after the first client - # (the post-kill counter latch bug). seen_pids still guards - # replays of old pids; reset immediately instead. + if pending_pid != p: + pending_pid = p + pending_count = 1 + log("semfix: pid change %d -> %d (debounce; reset if it " + "repeats)" % (last_pid, p)) + continue + pending_count += 1 + if pending_count < 2: + continue + # Same unseen pid reported on two consecutive polls: real new + # client. seen_pids keeps old pids from ever triggering this. seen_pids.add(p) + pending_pid = None + pending_count = 0 stream.reset() known_sems.clear() seen_sem_pin.clear() @@ -375,7 +366,6 @@ def main(): seen_ch.clear() seen_pb.clear() counter_pids.clear() - counter_dead.clear() sem_pin_fail.clear() sem_pin_skip_until.clear() unread_count.clear() @@ -392,7 +382,6 @@ def main(): # as a fallback for channel/pushbuffer discovery and to recover sems # the scanner may have missed. if loop % TRACE_EVERY == 0: - _hb() try: t_sems, t_pbs, t_chans = guest_trace() except Exception: @@ -553,7 +542,6 @@ def main(): log("semfix: pb=0x%x pushbuf miss [%s]" % (pb, diag_str(d))) if DLOG: - _hb() dmesg_releases(dseen) # Retry incomplete push-buffer pins: gva2gpa of the kernel vmalloc @@ -571,32 +559,20 @@ def main(): # block for its whole timeout under client load, so retry on a slow # cadence: hammering the agent here starves it and wedges the run. if last_pid is None and loop % TRACE_EVERY == 0: - _hb() last_pid = cdt_pid() _hb() if last_pid: seen_pids.add(last_pid) log("counter: client pid %d (agent)" % last_pid) - if last_pid and last_pid not in counter_pids \ - and last_pid not in counter_dead: + if last_pid and last_pid not in counter_pids: now = time.time() if now >= counter_next_try.get(last_pid, 0): + try: + pin_counter_page(last_pid, counter_pids) + except Exception as e: + log("counter: pin failed: %s" % e) _hb() - if not pid_alive(last_pid): - # Killed clients stay latched as last_pid forever; probe - # first so the 10 s cadence does not block the agent for a - # full 25 s exec on every retry (the post-kill hammering - # that starved the scanner). A new client's #pid resets - # counter_dead and takes over below. - log("counter: pid %d is gone - dropping" % last_pid) - counter_dead.add(last_pid) - else: - try: - pin_counter_page(last_pid, counter_pids) - except Exception as e: - log("counter: pin failed: %s" % e) - _hb() - counter_next_try[last_pid] = now + COUNTER_RETRY_S + counter_next_try[last_pid] = now + COUNTER_RETRY_S time.sleep(interval) |