This adds support for visiting abandoned pages in mimalloc and improves
the performance of the page visiting code. Abandoned pages contain
memory blocks from threads that have exited. At some point, they may be
later reclaimed by other threads. We still need to visit those pages in
the free-threaded GC because they contain live objects.
This also reduces the overhead of visiting mimalloc pages:
* Special cases for full, empty, and pages containing only a single
block.
* Fix free_map to use one bit instead of one byte per block.
* Use fast integer division by a constant algorithm when computing
block offset from block size and index.
Always set a _MainThread as a main thread after os.fork() is called from
a thread started not by the threading module.
A new _MainThread was already set as a new main thread after fork if
threading.current_thread() was not called for a foreign thread before fork.
Now, if it was called before fork, the implicitly created _DummyThread will
be turned into _MainThread after fork.
It fixes, in particularly, an incompatibility of _DummyThread with
the threading shutdown logic which relies on the main thread
having tstate_lock.
Co-authored-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
The terminal CR -> NL mapping setting should be inherited in cbreak mode as OSes do not specify altering it as part of their stty cbreak mode definition.
* Fix writing the retrieved binary file to stdout.
* Add a newline after writing warnings to stderr.
* Fix a TypeError if the netrc file doesn't contain a host/default entry.
* Improve the usage message.
Some socket tests related to sending file descriptors cause a file descriptor leak on macOS, all of them tests that send one or more descriptors than cannot be received on the read end. This appears to be a platform bug.
This PR skips those tests when doing a refleak test run to avoid hiding other problems.
I believe I added this while chasing some performance of hash functions
when I first created hashlib. It hasn't been used since, is frankly
trivial, and not a test.
* gh-112529: Use GC heaps for GC allocations in free-threaded builds
The free-threaded build's garbage collector implementation will need to
find GC objects by traversing mimalloc heaps. This hooks up the
allocation calls with the correct heaps by using a thread-local
"current_obj_heap" variable.
* Refactor out setting heap based on type
The GH-93000 change set inadvertently caused a sentence in re.compile()
documentation to refer to details that no longer followed. Correct this
with a link to the Flags sub-subsection.
Co-authored-by: Adam Turner <9087854+aa-turner@users.noreply.github.com>
Use `_make_child_entry()` rather than `_make_child_relpath()` to retrieve
path objects for directories to visit. This saves the allocation of one
path object per directory in user subclasses of `PathBase`, and avoids a
second loop.
This trick does not apply when walking top-down, because users can affect
the walk by modifying *dirnames* in-place.
A side effect of this change is that, in bottom-up mode, subdirectories of
each directory are visited in reverse order, and that this order doesn't
match that of the names in *dirnames*. I suspect this is fine as the
order is arbitrary anyway.
Allow `os.PathLike` objects to be passed as patterns to `pathlib.Path.glob()` and `rglob()`. (It's already possible to use them in `PurePath.match()`)
While we're in the area:
- Allow empty glob patterns in `PathBase` (but not `Path`)
- Speed up globbing in `PathBase` by generating paths with trailing slashes only as a final step, rather than for every intermediate directory.
- Simplify and speed up handling of rare patterns involving both `**` and `..` segments.
Use a ring buffer instead of a Python list in order to simplify the
process of making queue.SimpleQueue thread-safe in free-threaded
builds. The ring buffer implementation has no places where critical
sections may be released.
