jc211
/
tractor
forked from goodboy/tractor
1
0
Fork 0
Code Pull Requests Activity

Move all module vars into a `Lock` type

sigintsaviour_citesthackin
Tyler Goodlet 2022-07-29 16:03:26 -04:00
parent 4366873582
commit e6ad7a117b
2 changed files with 82 additions and 91 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
tractor/_actor.py
View File

@ -967,7 +967,7 @@ class Actor:
# don't start entire actor runtime
# cancellation if this actor is in debug
# mode
pdb_complete = _debug._local_pdb_complete
pdb_complete = _debug.Lock.local_pdb_complete
if pdb_complete:
await pdb_complete.wait()
@ -1413,7 +1413,7 @@ class Actor:
# kill any debugger request task to avoid deadlock
# with the root actor in this tree
dbcs = _debug._debugger_request_cs
dbcs = _debug.Lock._debugger_request_cs
if dbcs is not None:
log.cancel("Cancelling active debugger request")
dbcs.cancel()

151
tractor/_debug.py
View File

@ -33,6 +33,7 @@ from typing import (
)
from types import FrameType
from msgspec import Struct
import tractor
import trio
from trio_typing import TaskStatus
@ -60,27 +61,39 @@ log = get_logger(__name__)
__all__ = ['breakpoint', 'post_mortem']
# TODO: wrap all these in a static global class: ``DebugLock`` maybe?
class Lock:
'''
Actor global debug lock state.
Mostly to avoid a lot of ``global`` declarations for now XD.
'''
# placeholder for function to set a ``trio.Event`` on debugger exit
_pdb_release_hook: Optional[Callable] = None
pdb_release_hook: Optional[Callable] = None
# actor-wide variable pointing to current task name using debugger
_local_task_in_debug: Optional[str] = None
local_task_in_debug: Optional[str] = None
# actor tree-wide actor uid that supposedly has the tty lock
_global_actor_in_debug: Optional[Tuple[str, str]] = None
global_actor_in_debug: Optional[Tuple[str, str]] = None
local_pdb_complete: Optional[trio.Event] = None
no_remote_has_tty: Optional[trio.Event] = None
# lock in root actor preventing multi-access to local tty
_debug_lock: trio.StrictFIFOLock = trio.StrictFIFOLock()
_local_pdb_complete: Optional[trio.Event] = None
_no_remote_has_tty: Optional[trio.Event] = None
# XXX: set by the current task waiting on the root tty lock
# and must be cancelled if this actor is cancelled via message
# otherwise deadlocks with the parent actor may ensure
_debugger_request_cs: Optional[trio.CancelScope] = None
@classmethod
def maybe_release(cls):
cls.local_task_in_debug = None
if cls.pdb_release_hook:
cls.pdb_release_hook()
class TractorConfig(pdbpp.DefaultConfig):
"""Custom ``pdbpp`` goodness.
@ -108,13 +121,13 @@ class MultiActorPdb(pdbpp.Pdb):
try:
super().set_continue()
finally:
maybe_release()
Lock.maybe_release()
def set_quit(self):
try:
super().set_quit()
finally:
maybe_release()
Lock.maybe_release()
# TODO: will be needed whenever we get to true remote debugging.
@ -153,14 +166,6 @@ class MultiActorPdb(pdbpp.Pdb):
# log.info("Closing stdin hijack")
# break
# TODO: make this method on a global lock type!
def maybe_release():
global _local_task_in_debug, _pdb_release_hook
_local_task_in_debug = None
if _pdb_release_hook:
_pdb_release_hook()
@acm
async def _acquire_debug_lock(
uid: Tuple[str, str]
@ -175,8 +180,6 @@ async def _acquire_debug_lock(
to the ``pdb`` repl.
'''
global _debug_lock, _global_actor_in_debug, _no_remote_has_tty
task_name = trio.lowlevel.current_task().name
log.runtime(
@ -190,15 +193,15 @@ async def _acquire_debug_lock(
f"entering lock checkpoint, remote task: {task_name}:{uid}"
)
we_acquired = True
await _debug_lock.acquire()
await Lock._debug_lock.acquire()
if _no_remote_has_tty is None:
if Lock.no_remote_has_tty is None:
# mark the tty lock as being in use so that the runtime
# can try to avoid clobbering any connection from a child
# that's currently relying on it.
_no_remote_has_tty = trio.Event()
Lock.no_remote_has_tty = trio.Event()
_global_actor_in_debug = uid
Lock.global_actor_in_debug = uid
log.runtime(f"TTY lock acquired, remote task: {task_name}:{uid}")
# NOTE: critical section: this yield is unshielded!
@ -211,32 +214,32 @@ async def _acquire_debug_lock(
# surrounding caller side context should cancel normally
# relaying back to the caller.
yield _debug_lock
yield Lock._debug_lock
finally:
# if _global_actor_in_debug == uid:
# if Lock.global_actor_in_debug == uid:
if (
we_acquired
and _debug_lock.locked()
and Lock._debug_lock.locked()
):
_debug_lock.release()
Lock._debug_lock.release()
# IFF there are no more requesting tasks queued up fire, the
# "tty-unlocked" event thereby alerting any monitors of the lock that
# we are now back in the "tty unlocked" state. This is basically
# and edge triggered signal around an empty queue of sub-actor
# tasks that may have tried to acquire the lock.
stats = _debug_lock.statistics()
stats = Lock._debug_lock.statistics()
if (
not stats.owner
):
log.runtime(f"No more tasks waiting on tty lock! says {uid}")
if _no_remote_has_tty is not None:
_no_remote_has_tty.set()
_no_remote_has_tty = None
if Lock.no_remote_has_tty is not None:
Lock.no_remote_has_tty.set()
Lock.no_remote_has_tty = None
_global_actor_in_debug = None
Lock.global_actor_in_debug = None
log.runtime(
f"TTY lock released, remote task: {task_name}:{uid}"
@ -348,10 +351,8 @@ async def wait_for_parent_stdin_hijack(
debug (see below inside ``maybe_wait_for_debugger()``).
'''
global _debugger_request_cs
with trio.CancelScope(shield=True) as cs:
_debugger_request_cs = cs
Lock._debugger_request_cs = cs
try:
async with get_root() as portal:
@ -371,9 +372,9 @@ async def wait_for_parent_stdin_hijack(
# unblock local caller
try:
assert _local_pdb_complete
assert Lock.local_pdb_complete
task_status.started(cs)
await _local_pdb_complete.wait()
await Lock.local_pdb_complete.wait()
finally:
# TODO: shielding currently can cause hangs...
@ -390,8 +391,7 @@ async def wait_for_parent_stdin_hijack(
finally:
log.pdb(f"Exiting debugger for actor {actor_uid}")
global _local_task_in_debug
_local_task_in_debug = None
Lock.local_task_in_debug = None
log.pdb(f"Child {actor_uid} released parent stdio lock")
@ -440,9 +440,6 @@ async def _breakpoint(
actor = tractor.current_actor()
task_name = trio.lowlevel.current_task().name
global _local_pdb_complete, _pdb_release_hook
global _local_task_in_debug, _global_actor_in_debug
# TODO: is it possible to debug a trio.Cancelled except block?
# right now it seems like we can kinda do with by shielding
# around ``tractor.breakpoint()`` but not if we move the shielded
@ -450,14 +447,14 @@ async def _breakpoint(
# with trio.CancelScope(shield=shield):
# await trio.lowlevel.checkpoint()
if not _local_pdb_complete or _local_pdb_complete.is_set():
_local_pdb_complete = trio.Event()
if not Lock.local_pdb_complete or Lock.local_pdb_complete.is_set():
Lock.local_pdb_complete = trio.Event()
# TODO: need a more robust check for the "root" actor
if actor._parent_chan and not is_root_process():
if _local_task_in_debug:
if _local_task_in_debug == task_name:
if Lock.local_task_in_debug:
if Lock.local_task_in_debug == task_name:
# this task already has the lock and is
# likely recurrently entering a breakpoint
return
@ -467,18 +464,18 @@ async def _breakpoint(
# support for recursive entries to `tractor.breakpoint()`
log.warning(f"{actor.uid} already has a debug lock, waiting...")
await _local_pdb_complete.wait()
await Lock.local_pdb_complete.wait()
await trio.sleep(0.1)
# mark local actor as "in debug mode" to avoid recurrent
# entries/requests to the root process
_local_task_in_debug = task_name
Lock.local_task_in_debug = task_name
def child_release():
try:
# sometimes the ``trio`` might already be termianated in
# which case this call will raise.
_local_pdb_complete.set()
Lock.local_pdb_complete.set()
finally:
# restore original sigint handler
undo_sigint()
@ -486,7 +483,8 @@ async def _breakpoint(
# _local_task_in_debug = None
# assign unlock callback for debugger teardown hooks
_pdb_release_hook = child_release
Lock.pdb_release_hook = child_release
# _pdb_release_hook = child_release
# this **must** be awaited by the caller and is done using the
# root nursery so that the debugger can continue to run without
@ -503,66 +501,63 @@ async def _breakpoint(
actor.uid,
)
except RuntimeError:
_pdb_release_hook()
Lock.pdb_release_hook()
# _pdb_release_hook()
raise
elif is_root_process():
# we also wait in the root-parent for any child that
# may have the tty locked prior
global _debug_lock
# TODO: wait, what about multiple root tasks acquiring it though?
# root process (us) already has it; ignore
if _global_actor_in_debug == actor.uid:
if Lock.global_actor_in_debug == actor.uid:
return
# XXX: since we need to enter pdb synchronously below,
# we have to release the lock manually from pdb completion
# callbacks. Can't think of a nicer way then this atm.
if _debug_lock.locked():
if Lock._debug_lock.locked():
log.warning(
'Root actor attempting to shield-acquire active tty lock'
f' owned by {_global_actor_in_debug}')
f' owned by {Lock.global_actor_in_debug}')
# must shield here to avoid hitting a ``Cancelled`` and
# a child getting stuck bc we clobbered the tty
with trio.CancelScope(shield=True):
await _debug_lock.acquire()
await Lock._debug_lock.acquire()
else:
# may be cancelled
await _debug_lock.acquire()
await Lock._debug_lock.acquire()
_global_actor_in_debug = actor.uid
_local_task_in_debug = task_name
Lock.global_actor_in_debug = actor.uid
Lock.local_task_in_debug = task_name
# the lock must be released on pdb completion
def root_release():
global _local_pdb_complete, _debug_lock
global _global_actor_in_debug, _local_task_in_debug
try:
_debug_lock.release()
Lock._debug_lock.release()
except RuntimeError:
# uhhh makes no sense but been seeing the non-owner
# release error even though this is definitely the task
# that locked?
owner = _debug_lock.statistics().owner
owner = Lock._debug_lock.statistics().owner
if owner:
raise
_global_actor_in_debug = None
_local_task_in_debug = None
Lock.global_actor_in_debug = None
Lock.local_task_in_debug = None
try:
# sometimes the ``trio`` might already be termianated in
# which case this call will raise.
_local_pdb_complete.set()
Lock.local_pdb_complete.set()
finally:
# restore original sigint handler
undo_sigint()
_pdb_release_hook = root_release
# _pdb_release_hook = root_release
Lock.pdb_release_hook = root_release
try:
# block here one (at the appropriate frame *up*) where
@ -571,7 +566,7 @@ async def _breakpoint(
debug_func(actor, pdb)
except bdb.BdbQuit:
maybe_release()
Lock.maybe_release()
raise
# XXX: apparently we can't do this without showing this frame
@ -607,8 +602,7 @@ def shield_sigint(
'''
__tracebackhide__ = True
global _local_task_in_debug, _global_actor_in_debug
uid_in_debug = _global_actor_in_debug
uid_in_debug = Lock.global_actor_in_debug
actor = tractor.current_actor()
@ -681,7 +675,7 @@ def shield_sigint(
)
return do_cancel()
task = _local_task_in_debug
task = Lock.local_task_in_debug
if task:
log.pdb(
f"Ignoring SIGINT while task in debug mode: `{task}`"
@ -754,8 +748,7 @@ def _set_trace(
pdb, undo_sigint = mk_mpdb()
# we entered the global ``breakpoint()`` built-in from sync code?
global _local_task_in_debug, _pdb_release_hook
_local_task_in_debug = 'sync'
Lock.local_task_in_debug = 'sync'
pdb.set_trace(frame=frame)
@ -830,7 +823,7 @@ async def _maybe_enter_pm(err):
):
log.debug("Actor crashed, entering debug mode")
await post_mortem()
maybe_release()
Lock.maybe_release()
return True
else:
@ -875,8 +868,6 @@ async def maybe_wait_for_debugger(
if (
is_root_process()
):
global _no_remote_has_tty, _global_actor_in_debug, _wait_all_tasks_lock
# If we error in the root but the debugger is
# engaged we don't want to prematurely kill (and
# thus clobber access to) the local tty since it
@ -888,8 +879,8 @@ async def maybe_wait_for_debugger(
for _ in range(poll_steps):
if _global_actor_in_debug:
sub_in_debug = tuple(_global_actor_in_debug)
if Lock.global_actor_in_debug:
sub_in_debug = tuple(Lock.global_actor_in_debug)
# alive = tractor.current_actor().child_alive(sub_in_debug)
# if not alive:
# break
@ -905,7 +896,7 @@ async def maybe_wait_for_debugger(
# XXX: doesn't seem to work
# await trio.testing.wait_all_tasks_blocked(cushion=0)
debug_complete = _no_remote_has_tty
debug_complete = Lock.no_remote_has_tty
if (
(debug_complete and
not debug_complete.is_set())