fix(kad): compute jobs_query_capacity accurately

protocols/kad/CHANGELOG.md

@@ -5,6 +5,8 @@
 - Make it mandatory to provide protocol names when creating a `kad::Config`.
  Deprecate `kad::Config::default()`, replaced by `kad::Config::new(StreamProtocol)`.
  See [PR 5122](https://github.com/libp2p/rust-libp2p/pull/5122).
+- Compute `jobs_query_capacity` accurately.
+ See [PR 5148](https://github.com/libp2p/rust-libp2p/pull/5148).
 
 ## 0.45.3
 

protocols/kad/src/behaviour.rs

@@ -2502,14 +2502,14 @@ where
  // Run the periodic provider announcement job.
  if let Some(mut job) = self.add_provider_job.take() {
  let num = usize::min(JOBS_MAX_NEW_QUERIES, jobs_query_capacity);
- for _ in 0..num {
+ for i in 0..num {
  if let Poll::Ready(r) = job.poll(cx, &mut self.store, now) {
  self.start_add_provider(r.key, AddProviderContext::Republish)
  } else {
+ jobs_query_capacity -= i;
  break;
  }
  }
- jobs_query_capacity -= num;
  self.add_provider_job = Some(job);
  }