Isolate the faulthandler Module Between Interpreters

Ninguém assumiu esta issue ainda.

(See gh-100227.)

Currently the faulthandler module has some state in _PyRuntimeState, including objects, which is shared by all interpreters. Interpreters should be isolated from each other, for a variety of reasons (including the possibility of a per-interpreter GIL). Isolating the module will involve moving some of the state to PyInterpreterState (and, under per-interpreter GIL, guarding other state with a global lock).

Code Analysis:

(expand)

Signals

The module installs handlers for various signals.

(expand)

fatal:

SIGBUS - bus error
SIGILL - illegal instruction
SIGFPE - floating point exception
SIGABRT - abort
SIGSEGV - segfault

"user":

the 5 fatal signals
others (up to Py_NSIG)

handlers:

faulthandler_fatal_error(signum)
faulthandler_exc_handler() (on Windows)
faulthandler_user()

State

Fields

https://github.com/python/cpython/blob/main/Include/internal/pycore_faulthandler.h#L49-L86
https://github.com/python/cpython/blob/main/Include/internal/pycore_runtime.h#L146

raw

https://github.com/python/cpython/blob/62251c3da06eb4662502295697f39730565b1717/Include/internal/pycore_faulthandler.h#L49-L86
https://github.com/python/cpython/blob/62251c3da06eb4662502295697f39730565b1717/Include/internal/pycore_faulthandler.h#L36-L46

tables:

name	type	#ifdef	notes
`fatal_error`
. `enabled`	`bool`		"is faulthandler enabled?"
. `file`	*`PyObject `**		only for keeping `.fd` alive
. `fd`	`int`
. `all_threads`	`bool`
. `interp`	*`PyInterpreterState `**		show only its threads the one that enabled faulthandler
. `exc_handler`	`void *`	`MS_WINDOWS`

name	type	#ifdef	notes
`thread`	---
. `file`	`PyObject `*		only for keeping `.fd` alive
. `fd`	`int`		defaults to `sys.stderr`
. `timeout_us`	`PY_TIMEOUT_T`
. `repeat`	`bool`
. `interp`	*`PyInterpreterState `**		show only its threads the one that requested the info
. `exit`	`bool`
. `header`	`char *`
. `header_len`	`size_t`
. `cancel_event`	`PyThread_type_lock`
. `running`	`PyThread_type_lock`
name	type	#ifdef	notes
`user_signals`	*`struct faulthandler_user_signal `**	`FAULTHANDLER_USER`	a dynamically allocated array (`Py_NSIG`)
`user_signals[signum]`	---
. `enabled`	`bool`
. `file`	`PyObject *`
. `fd`	`int`
. `all_threads`	`bool`
. `chain`	`bool`
. `previous`	`_Py_sighandler_t`
. `interp`	*`PyInterpreterState `**		show only its threads the one that added the handler
name	type	#ifdef	notes
`old_stack`	`stack_t`	`FAULTHANDLER_USE_ALT_STACK`
`stack`	`stack_t`	`FAULTHANDLER_USE_ALT_STACK`

Usage

simple:

name	context	get	set
`fatal_error`
. `enabled`	module	`faulthandler_is_enabled()`	`faulthandler_disable_py()`
	signal	`faulthandler_fatal_error()`
	internal	`faulthandler_enable()` `faulthandler_disable()`	`faulthandler_enable()` `faulthandler_disable()`
. `file`	module	`faulthandler_traverse()`	`faulthandler_py_enable()` `faulthandler_traverse()`
	internal	`faulthandler_disable()`	`faulthandler_disable()`
. `fd`		module
	signal	`faulthandler_fatal_error()` `faulthandler_exc_handler()`
. `all_threads`	module		`faulthandler_py_enable()`
	signal	`faulthandler_fatal_error()` `faulthandler_exc_handler()`
. `interp`	module		`faulthandler_py_enable()`
	internal	`faulthandler_fatal_error()` `faulthandler_exc_handler()`
. `exc_handler`	internal	`faulthandler_enable()` `faulthandler_disable()`	`faulthandler_enable()` `faulthandler_disable()`

name	context	get	set
`thread`
. `file`	module	`faulthandler_dump_traceback_later()` `faulthandler_traverse()`	`faulthandler_dump_traceback_later()` `faulthandler_traverse()`
	internal	`cancel_dump_traceback_later()`	`cancel_dump_traceback_later()`
. `fd`
module		`faulthandler_dump_traceback_later()`
	thread	`faulthandler_thread()`
. `timeout_us`	module		`faulthandler_dump_traceback_later()`
	thread	`faulthandler_thread()`
. `repeat`	module		`faulthandler_dump_traceback_later()`
	thread	`faulthandler_thread()`
. `interp`	module		`faulthandler_dump_traceback_later()`
	thread	`faulthandler_thread()`
. `exit`	module		`faulthandler_dump_traceback_later()`
	thread	`faulthandler_thread()`
. `header`	module		`faulthandler_dump_traceback_later()`
	thread	`faulthandler_thread()`
	internal	`cancel_dump_traceback_later()`	`cancel_dump_traceback_later()`
. `header_len`	module		`faulthandler_dump_traceback_later()`
	thread	`faulthandler_thread()`
. `cancel_event`	module	`faulthandler_dump_traceback_later()`	`faulthandler_dump_traceback_later()`
	thread	`faulthandler_thread()`
	internal	`cancel_dump_traceback_later()`
. `running`	module	`faulthandler_dump_traceback_later()`	`faulthandler_dump_traceback_later()`
	thread	`faulthandler_thread()`
	internal	`cancel_dump_traceback_later()`
name	context	get	set
`user_signals`	module	`faulthandler_register_py()` `faulthandler_unregister_py()`	`faulthandler_register_py()` `faulthandler_traverse()`
	C-API	`_PyFaulthandler_Fini()`	`_PyFaulthandler_Fini()`
	signal	`faulthandler_user()`
`user_signals[signum]`
. `enabled`	module	`faulthandler_register_py()`	`faulthandler_register_py()`
	signal	`faulthandler_user()`
	internal	`faulthandler_unregister()`	`faulthandler_unregister()`
. `file`	module	`faulthandler_register_py()` `faulthandler_traverse()`	`faulthandler_register_py()` `faulthandler_traverse()`
	internal	`faulthandler_unregister()`	`faulthandler_unregister()`
. `fd`	module		`faulthandler_register_py()`
	signal	`faulthandler_user()`
	internal		`faulthandler_unregister()`
. `all_threads`	module		`faulthandler_register_py()`
	signal	`faulthandler_user()`
. `chain`	module		`faulthandler_register_py()`
	signal	`faulthandler_user()`
. `previous`	module		`faulthandler_register_py()`
	signal	`faulthandler_user()`
	internal	`faulthandler_unregister()`
. `interp`	module		`faulthandler_register_py()`
	signal	`faulthandler_user()`
name	context	get	set
`stack`	C-API	`_PyFaulthandler_Init()` `_PyFaulthandler_Fini()`
	internal	`faulthandler_enable()` `faulthandler_register()` `faulthandler_allocate_stack()`
`old_stack`	C-API	`_PyFaulthandler_Fini()`

modify data in complex fields:

name	context	calls
`fatal_error .fd`	signal	`faulthandler_fatal_error()` -> `faulthandler_dump_traceback()` `faulthandler_fatal_error()` -> `_Py_DumpExtensionModules()` `faulthandler_exc_handler()` `faulthandler_exc_handler()` -> `_Py_DumpHexadecimal()` `faulthandler_exc_handler()` -> `faulthandler_dump_traceback()`
`thread.fd`	thread	`faulthandler_thread()` -> `_Py_write_noraise()` `faulthandler_thread()` -> `_Py_DumpTracebackThreads()`
`thread .cancel_event`	module	`faulthandler_dump_traceback_later()`
	C-API	`_PyFaulthandler_Fini()`
	thread	`faulthandler_thread()`
	internal	`cancel_dump_traceback_later()`
`thread .running`	module	`faulthandler_dump_traceback_later()`
	thread	`faulthandler_thread()`
	internal	`cancel_dump_traceback_later()`
`user_signals[signum] .fd`	signal	`faulthandler_user()` -> `faulthandler_dump_traceback()`
`stack`	C-API	`_PyFaulthandler_Init()` `_PyFaulthandler_Fini()`
	internal	`faulthandler_allocate_stack()`
`old_stack`	internal	`faulthandler_allocate_stack()` -> `sigaltstack()`

Comece por Include/internal/pycore_faulthandler.h e Include/internal/pycore_runtime.h e, em seguida, rastreie os pontos de entrada listados, como _PyFaulthandler_Init(), _PyFaulthandler_Fini(), faulthandler_enable() e faulthandler_user(). Mapeie cada campo compartilhado das tabelas de estado para sua propriedade no interpretador ou global e verifique se o estado de faulthandler está isolado sem quebrar o comportamento dos manipuladores de sinais.

Escrita pelo modelo de indexação a partir do texto da issue.

Descrição

Signals

State

Fields

Usage

Guia de contribuição

Primeiros passos

Direção de pesquisa

Avaliação

Isolate the faulthandler Module Between Interpreters

Descrição

Signals

State

Fields

Usage

Guia de contribuição

Primeiros passos

Direção de pesquisa

Avaliação

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