An internal do_insert_with_hash method gets the current Instant too early when eviction listener is enabled

[tatsuya6502]

Relates to:

• wasm compatibility - change Expiry to avoid needing std::time::Instant::now() #321

As of moka v0.12.0-beta.2, an internal method do_insert_with_hash gets the ts (the base Instant, or the time that upsert is about to be performed at) before acquiring the key-level lock for notifying to the eviction listener. This could make the base instant much earlier than the actual time that the entry was upserted at, because it can take some time until the lock becomes available.

Therefore, we should change it to get the base instant after acquiring the lock.

Later, the base instant is passed to an Expiry method as the current_time, and when the expiry method returns, it is used to calculate the expiration time from the returned expiry duration. (expires_at = current_time + returned_duration). The base instant is also used by the time-to-live and time-to-idle that can be set at the cache creation time.

moka/src/sync_base/base_cache.rs

Lines 483 to 492 in a03488b

	let ts = self.current_time_from_expiration_clock();
	let weight = self.inner.weigh(&key, &value);
	let op_cnt1 = Rc::new(AtomicU8::new(0));
	let op_cnt2 = Rc::clone(&op_cnt1);
	let mut op1 = None;
	let mut op2 = None;
	// Lock the key for update if blocking removal notification is enabled.
	let kl = self.maybe_key_lock(&key);
	let _klg = &kl.as_ref().map(|kl| kl.lock());

moka/src/future/base_cache.rs

Lines 477 to 490 in a03488b

	let ts = self.current_time_from_expiration_clock();
	let weight = self.inner.weigh(&key, &value);
	let op_cnt1 = Arc::new(AtomicU8::new(0));
	let op_cnt2 = Arc::clone(&op_cnt1);
	let mut op1 = None;
	let mut op2 = None;
	// Lock the key for update if blocking removal notification is enabled.
	let kl = self.maybe_key_lock(&key);
	let _klg = if let Some(lock) = &kl {
	Some(lock.lock().await)
	} else {
	None
	};

Action Items

• Fix v0.12.x via Get the last modified time for upsert after acquiring key level lock #324.
• Release v0.12.0.
• Fix v0.11.x.
• Release v0.11.4.

[tatsuya6502]

Reopen for back-porting #324 to v0.11.x.