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AgeCommit message (Collapse)Author
2023-04-04More efficient IO loop event execution to avoid long loopsMaria Matejka
If there are lots of loops in a single thread and only some of the loops are actually active, the other loops are now kept aside and not checked until they actually get some timers, events or active sockets. This should help with extreme loads like 100k tables and protocols. Also ping and loop pickup mechanism was allowing subtle race conditions. Now properly handling collisions between loop ping and pickup.
2023-01-19Decoupling loops from threads to allow fixed thread countMaria Matejka
On large configurations, too many threads would spawn with one thread per loop. Therefore, threads may now run multiple loops at once. The thread count is configurable and may be changed during run. All threads are spawned on startup. This change helps with memory bloating. BIRD filters need large temporary memory blocks to store their stack and also memory management keeps its hot page storage per-thread. Known bugs: * Thread autobalancing is not yet implemented. * Low latency loops are executed together with standard loops.
2022-09-18Routing tables have their own service loops.Maria Matejka
2022-08-02Merge commit 'f0507f05ce57398e135651896dace4cb68eeed54' into thread-nextMaria Matejka
2022-08-02Introducing basic RCU primitives for lock-less shared data structuresMaria Matejka
2022-07-18Event lists rewritten to a single linked listMaria Matejka
In multithreaded environment, we need to pass messages between workers. This is done by queuing events to their respective queues. The double-linked list is not really useful for that as it needs locking everywhere. This commit rewrites the event subsystem to use a single-linked list where events are enqueued by a single atomic instruction and the queue is processed after atomically moving the whole queue aside.
2021-11-22Route sources have an explicit ownerMaria Matejka
This commit prevents use-after-free of routes belonging to protocols which have been already destroyed, delaying also all the protocols' shutdown until all of their routes have been finally propagated through all the pipes down to the appropriate exports. The use-after-free was somehow hypothetic yet theoretically possible in rare conditions, when one BGP protocol authors a lot of routes and the user deletes that protocol by reconfiguring in the same time as next hop update is requested, causing rte_better() to be called on a not-yet-pruned network prefix while the owner protocol has been already freed. In parallel execution environments, this would happen an inter-thread use-after-free, causing possible heisenbugs or other nasty problems.
2021-11-22Converting the former BFD loop to a universal IO loop and protocol loop.Maria Matejka
There is a simple universal IO loop, taking care of events, timers and sockets. Primarily, one instance of a protocol should use exactly one IO loop to do all its work, as is now done in BFD. Contrary to previous versions, the loop is now launched and cleaned by the nest/proto.c code, allowing for a protocol to just request its own loop by setting the loop's lock order in config higher than the_bird. It is not supported nor checked if any protocol changed the requested lock order in reconfigure. No protocol should do it at all.
2021-11-22Adding a generic cork mechanism for eventsMaria Matejka
2021-11-22Lock position checking allows for safe lock unionsMaria Matejka
2021-11-22Locking subsystem: Just a global BIRD lock to begin with.Maria Matejka