Mercurial > cpython-lru_cache-weakref
diff Python/thread.c @ 48217:eefe4450f773 2.5
Backport r60148 and r65481: sanity checks to avoid infinite loops.
| author | Georg Brandl <georg@python.org> |
|---|---|
| date | Tue, 12 Aug 2008 08:46:02 +0000 |
| parents | 7c09b66f04bd |
| children | 8d902c513ba0 |
line wrap: on
line diff
--- a/Python/thread.c Tue Aug 12 08:39:33 2008 +0000 +++ b/Python/thread.c Tue Aug 12 08:46:02 2008 +0000 @@ -264,15 +264,25 @@ static struct key * find_key(int key, void *value) { - struct key *p; + struct key *p, *prev_p; long id = PyThread_get_thread_ident(); if (!keymutex) return NULL; PyThread_acquire_lock(keymutex, 1); + prev_p = NULL; for (p = keyhead; p != NULL; p = p->next) { if (p->id == id && p->key == key) goto Done; + /* Sanity check. These states should never happen but if + * they do we must abort. Otherwise we'll end up spinning in + * in a tight loop with the lock held. A similar check is done + * in pystate.c tstate_delete_common(). */ + if (p == prev_p) + Py_FatalError("tls find_key: small circular list(!)"); + prev_p = p; + if (p->next == keyhead) + Py_FatalError("tls find_key: circular list(!)"); } if (value == NULL) { assert(p == NULL);