Willy Tarreau ddedc16624 MEDIUM: fd: make fd_insert/fd_delete atomically update fd.tgid ... These functions need to set/reset the FD's tgid but when they're called there may still be wakeups on other threads that discover late updates and have to touch the tgid at the same time. As such, it is not possible to just read/write the tgid there. It must only be done using operations that are compatible with what other threads may be doing. As we're using inc/dec on the refcount, it's safe to AND the area to zero the lower part when resetting the value. However, in order to set the value, there's no other choice but fd_claim_tgid() which will assign it only if possible (via a CAS). This is convenient in the end because it protects the FD's masks from being modified by late threads, so while we hold this refcount we can safely reset the thread_mask and a few other elements. A debug test for non-null masks was added to fd_insert() as it must not be possible to face this situation thanks to the protection offered by the tgid.		2022-07-15 20:16:30 +02:00
..
haproxy	MEDIUM: fd: make fd_insert/fd_delete atomically update fd.tgid	2022-07-15 20:16:30 +02:00
import	CLEANUP: tree-wide: remove a few rare non-ASCII chars	2022-03-04 08:58:32 +01:00