Module job 

Structs

AbstractedWaiter 🔒

This abstracts over non-resumable waiters which are found in QueryJob’s parent field and resumable waiters are in latch field.

QueryJobInfo 🔒

QueryJobMap

Map from query job IDs to job information collected by collect_active_query_jobs.

Functions

abstracted_waiters_of 🔒

Returns all the non-resumable and resumable waiters of a query. This is used so we can uniformly loop over both non-resumable and resumable waiters.

break_query_cycles

Detects query cycles by using depth first search over all active query jobs. If a query cycle is found it will break the cycle by finding an edge which uses a query latch and then resuming that waiter. There may be multiple cycles involved in a deadlock, so this searches all active queries for cycles before finally resuming all the waiters at once.

connected_to_root 🔒

Finds out if there’s a path to the compiler root (aka. code which isn’t in a query) from query without going through any of the queries in visited. This is achieved with a depth first search.

create_cycle_error 🔒

find_cycle 🔒

Looks for a query cycle by doing a depth first search starting at query. span is the reason for the query to execute. This is initially DUMMY_SP. If a cycle is detected, this initial value is replaced with the span causing the cycle. stack will contain just the cycle on return if detected.

find_cycle_in_stack 🔒

find_dep_kind_root 🔒

Finds the query job closest to the root that is for the same query method as id (but not necessarily the same query key), and returns information about it.

print_query_stack

remove_cycle 🔒

Looks for a query cycle using the last query in jobs. If a cycle is found, all queries in the cycle is removed from jobs and the function return true. If a cycle was not found, the starting query is removed from jobs and the function returns false.

Type Aliases

ResumableWaiterLocation 🔒

The locaton of a resumable waiter. The usize is the index into waiters in the query’s latch. We’ll use this to remove the waiter using QueryLatch::extract_waiter if we’re waking it up.