René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Make hashlib related modules thread-safe without the GIL","articleBody":"# Feature or enhancement\r\n\r\nThe hashlib based modules already have some locking to make some operations thread-safe (with the GIL), but the logic isn't sufficient if running with the GIL disabled.\r\n\r\nRelevant files:\r\n* Modules/_blake2/blake2b_impl.c\r\n* Modules/_blake2/blake2s_impl.c\r\n* Modules/_hashopenssl.c\r\n* Modules/hashlib.h\r\n* Modules/md5module.c\r\n* Modules/sha1module.c\r\n* Modules/sha2module.c\r\n* Modules/sha3module.c\r\n\r\nBasic idea:\r\n1. Replace `PyThread_type_lock lock` with `PyMutex`. This should be both simpler and faster in general and avoid the need for dynamically assigning a lock, which can pose thread-safety issues without the GIL\r\n2. Add a field `bool use_mutex` to indicate if the code should lock the mutex. This should always be set to `true` in `Py_NOGIL`. In the default build, we should dynamically set it to `true` in places where we previously allocated `self-\u003elock`\r\n3. Update `ENTER_HASHLIB` and `EXIT_HASHLIB` macros.\r\n\r\n\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-111981\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/colesbury","@type":"Person","name":"colesbury"},"datePublished":"2023-11-09T21:09:57.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/111916/cpython/issues/111916"}