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Merged
awolverp merged 1 commit into from
Aug 9, 2026
+175 −53
Merged

Call the setdefault_with factory without holding the lock #68

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49 changes: 28 additions & 21 deletions cachebox/_core.pyi
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Original file line number Diff line number Diff line change
Expand Up @@ -384,16 +384,17 @@ class Cache(BaseCacheImpl[KT, VT]):
"""
Get `key`s value, or automatically create and insert one via `factory`.
If `key` exists, its current value is returned and `factory` is not called.
Otherwise `factory` is called exactly once under an internal lock, its
Otherwise `factory` is called with the internal lock released, its
result is inserted and returned.

Args:
key: The key to look up or insert.
factory: The factory to call and get default value from if ``key`` is not in the cache.

Warning:
`factory` must not call back into this cache (deadlock risk) or block
for long. If `factory` raises, nothing is inserted and the exception
if two threads miss the same key at once, `factory` can run
more than once; the value inserted first wins and is returned to
both. If `factory` raises, nothing is inserted and the exception
propagates.
"""
...
Expand Down Expand Up @@ -565,16 +566,17 @@ class FIFOCache(BaseCacheImpl[KT, VT]):
"""
Get `key`s value, or automatically create and insert one via `factory`.
If `key` exists, its current value is returned and `factory` is not called.
Otherwise `factory` is called exactly once under an internal lock, its
Otherwise `factory` is called with the internal lock released, its
result is inserted and returned.

Args:
key: The key to look up or insert.
factory: The factory to call and get default value from if ``key`` is not in the cache.

Warning:
`factory` must not call back into this cache (deadlock risk) or block
for long. If `factory` raises, nothing is inserted and the exception
if two threads miss the same key at once, `factory` can run
more than once; the value inserted first wins and is returned to
both. If `factory` raises, nothing is inserted and the exception
propagates.
"""
...
Expand Down Expand Up @@ -779,16 +781,17 @@ class RRCache(BaseCacheImpl[KT, VT]):
"""
Get `key`s value, or automatically create and insert one via `factory`.
If `key` exists, its current value is returned and `factory` is not called.
Otherwise `factory` is called exactly once under an internal lock, its
Otherwise `factory` is called with the internal lock released, its
result is inserted and returned.

Args:
key: The key to look up or insert.
factory: The factory to call and get default value from if ``key`` is not in the cache.

Warning:
`factory` must not call back into this cache (deadlock risk) or block
for long. If `factory` raises, nothing is inserted and the exception
if two threads miss the same key at once, `factory` can run
more than once; the value inserted first wins and is returned to
both. If `factory` raises, nothing is inserted and the exception
propagates.
"""
...
Expand Down Expand Up @@ -986,16 +989,17 @@ class LRUCache(BaseCacheImpl[KT, VT]):
"""
Get `key`s value, or automatically create and insert one via `factory`.
If `key` exists, its current value is returned and `factory` is not called.
Otherwise `factory` is called exactly once under an internal lock, its
Otherwise `factory` is called with the internal lock released, its
result is inserted and returned.

Args:
key: The key to look up or insert.
factory: The factory to call and get default value from if ``key`` is not in the cache.

Warning:
`factory` must not call back into this cache (deadlock risk) or block
for long. If `factory` raises, nothing is inserted and the exception
if two threads miss the same key at once, `factory` can run
more than once; the value inserted first wins and is returned to
both. If `factory` raises, nothing is inserted and the exception
propagates.
"""
...
Expand Down Expand Up @@ -1234,16 +1238,17 @@ class LFUCache(BaseCacheImpl[KT, VT]):
"""
Get `key`s value, or automatically create and insert one via `factory`.
If `key` exists, its current value is returned and `factory` is not called.
Otherwise `factory` is called exactly once under an internal lock, its
Otherwise `factory` is called with the internal lock released, its
result is inserted and returned.

Args:
key: The key to look up or insert.
factory: The factory to call and get default value from if ``key`` is not in the cache.

Warning:
`factory` must not call back into this cache (deadlock risk) or block
for long. If `factory` raises, nothing is inserted and the exception
if two threads miss the same key at once, `factory` can run
more than once; the value inserted first wins and is returned to
both. If `factory` raises, nothing is inserted and the exception
propagates.
"""
...
Expand Down Expand Up @@ -1441,16 +1446,17 @@ class TTLCache(BaseCacheImpl[KT, VT]):
"""
Get `key`s value, or automatically create and insert one via `factory`.
If `key` exists, its current value is returned and `factory` is not called.
Otherwise `factory` is called exactly once under an internal lock, its
Otherwise `factory` is called with the internal lock released, its
result is inserted and returned.

Args:
key: The key to look up or insert.
factory: The factory to call and get default value from if ``key`` is not in the cache.

Warning:
`factory` must not call back into this cache (deadlock risk) or block
for long. If `factory` raises, nothing is inserted and the exception
if two threads miss the same key at once, `factory` can run
more than once; the value inserted first wins and is returned to
both. If `factory` raises, nothing is inserted and the exception
propagates.
"""
...
Expand Down Expand Up @@ -1708,7 +1714,7 @@ class VTTLCache(BaseCacheImpl[KT, VT]):
"""
Get `key`s value, or automatically create and insert one via `factory`.
If `key` exists, its current value is returned and `factory` is not called.
Otherwise `factory` is called exactly once under an internal lock, its
Otherwise `factory` is called with the internal lock released, its
result is inserted and returned.

Args:
Expand All @@ -1717,8 +1723,9 @@ class VTTLCache(BaseCacheImpl[KT, VT]):
ttl: An optional time-to-live duration for item.

Warning:
`factory` must not call back into this cache (deadlock risk) or block
for long. If `factory` raises, nothing is inserted and the exception
if two threads miss the same key at once, `factory` can run
more than once; the value inserted first wins and is returned to
both. If `factory` raises, nothing is inserted and the exception
propagates.
"""
...
Expand Down
21 changes: 16 additions & 5 deletions src/pyclasses/cache.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -359,11 +359,12 @@ impl PyCache {
/// Get `key`s value, or automatically create and insert one via `factory`.
///
/// If `key` exists, its current value is returned and `factory` is not called.
/// Otherwise `factory` is called exactly once under an internal lock, its
/// Otherwise `factory` is called with the internal lock released, its
/// result is inserted and returned.
///
/// Warning: `factory` must not call back into this cache (deadlock risk) or block
/// for long. If `factory` raises, nothing is inserted and the exception
/// Warning: if two threads miss the same key at once, `factory` can run
/// more than once; the value inserted first wins and is returned to
/// both. If `factory` raises, nothing is inserted and the exception
/// propagates.
fn setdefault_with(
&self,
Expand All @@ -378,14 +379,24 @@ impl PyCache {

let inner = self.0.get();
let shared = inner.shared();

{
let mut policy = inner.policy();

if let Some(x) = policy.get(py, &key)? {
return Ok(x.value().clone_ref(py));
}
}

// `factory` is Python code: a GC pass inside it would deadlock on `__traverse__`
let default_object = factory.call0(py)?;

let mut policy = inner.policy();

if let Some(x) = policy.get(py, &key)? {
return Ok(x.value().clone_ref(py));
}

let default_object = factory.call0(py)?;

let handle = nopolicy::Handle::with_precomputed_hash_key(
py,
shared.getsizeof(),
Expand Down
21 changes: 16 additions & 5 deletions src/pyclasses/fifocache.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -365,11 +365,12 @@ impl PyFIFOCache {
/// Get `key`s value, or automatically create and insert one via `factory`.
///
/// If `key` exists, its current value is returned and `factory` is not called.
/// Otherwise `factory` is called exactly once under an internal lock, its
/// Otherwise `factory` is called with the internal lock released, its
/// result is inserted and returned.
///
/// Warning: `factory` must not call back into this cache (deadlock risk) or block
/// for long. If `factory` raises, nothing is inserted and the exception
/// Warning: if two threads miss the same key at once, `factory` can run
/// more than once; the value inserted first wins and is returned to
/// both. If `factory` raises, nothing is inserted and the exception
/// propagates.
fn setdefault_with(
&self,
Expand All @@ -384,14 +385,24 @@ impl PyFIFOCache {

let inner = self.0.get();
let shared = inner.shared();

{
let mut policy = inner.policy();

if let Some(x) = policy.get(py, &key)? {
return Ok(x.value().clone_ref(py));
}
}

// `factory` is Python code: a GC pass inside it would deadlock on `__traverse__`
let default_object = factory.call0(py)?;

let mut policy = inner.policy();

if let Some(x) = policy.get(py, &key)? {
return Ok(x.value().clone_ref(py));
}

let default_object = factory.call0(py)?;

let handle = fifopolicy::Handle::with_precomputed_hash_key(
py,
shared.getsizeof(),
Expand Down
21 changes: 16 additions & 5 deletions src/pyclasses/lfucache.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -384,11 +384,12 @@ impl PyLFUCache {
/// Get `key`s value, or automatically create and insert one via `factory`.
///
/// If `key` exists, its current value is returned and `factory` is not called.
/// Otherwise, `factory` is called exactly once under an internal lock, its
/// Otherwise, `factory` is called with the internal lock released, its
/// result is inserted and returned.
///
/// Warning: `factory` must not call back into this cache (deadlock risk) or block
/// for long. If `factory` raises, nothing is inserted and the exception
/// Warning: if two threads miss the same key at once, `factory` can run
/// more than once; the value inserted first wins and is returned to
/// both. If `factory` raises, nothing is inserted and the exception
/// propagates.
fn setdefault_with(
&self,
Expand All @@ -403,14 +404,24 @@ impl PyLFUCache {

let inner = self.0.get();
let shared = inner.shared();

{
let mut policy = inner.policy();

if let Some(x) = policy.get(py, &key)? {
return Ok(x.value().clone_ref(py));
}
}

// `factory` is Python code: a GC pass inside it would deadlock on `__traverse__`
let default_object = factory.call0(py)?;

let mut policy = inner.policy();

if let Some(x) = policy.get(py, &key)? {
return Ok(x.value().clone_ref(py));
}

let default_object = factory.call0(py)?;

let handle = lfupolicy::FrequencyHandle::with_precomputed_hash_key(
py,
shared.getsizeof(),
Expand Down
21 changes: 16 additions & 5 deletions src/pyclasses/lrucache.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -392,11 +392,12 @@ impl PyLRUCache {
/// Get `key`s value, or automatically create and insert one via `factory`.
///
/// If `key` exists, its current value is returned and `factory` is not called.
/// Otherwise `factory` is called exactly once under an internal lock, its
/// Otherwise `factory` is called with the internal lock released, its
/// result is inserted and returned.
///
/// Warning: `factory` must not call back into this cache (deadlock risk) or block
/// for long. If `factory` raises, nothing is inserted and the exception
/// Warning: if two threads miss the same key at once, `factory` can run
/// more than once; the value inserted first wins and is returned to
/// both. If `factory` raises, nothing is inserted and the exception
/// propagates.
fn setdefault_with(
&self,
Expand All @@ -411,14 +412,24 @@ impl PyLRUCache {

let inner = self.0.get();
let shared = inner.shared();

{
let mut policy = inner.policy();

if let Some(x) = policy.get(py, &key)? {
return Ok(x.value().clone_ref(py));
}
}

// `factory` is Python code: a GC pass inside it would deadlock on `__traverse__`
let default_object = factory.call0(py)?;

let mut policy = inner.policy();

if let Some(x) = policy.get(py, &key)? {
return Ok(x.value().clone_ref(py));
}

let default_object = factory.call0(py)?;

let handle = lrupolicy::Handle::with_precomputed_hash_key(
py,
shared.getsizeof(),
Expand Down
21 changes: 16 additions & 5 deletions src/pyclasses/rrcache.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -363,11 +363,12 @@ impl PyRRCache {
/// Get `key`s value, or automatically create and insert one via `factory`.
///
/// If `key` exists, its current value is returned and `factory` is not called.
/// Otherwise `factory` is called exactly once under an internal lock, its
/// Otherwise `factory` is called with the internal lock released, its
/// result is inserted and returned.
///
/// Warning: `factory` must not call back into this cache (deadlock risk) or block
/// for long. If `factory` raises, nothing is inserted and the exception
/// Warning: if two threads miss the same key at once, `factory` can run
/// more than once; the value inserted first wins and is returned to
/// both. If `factory` raises, nothing is inserted and the exception
/// propagates.
fn setdefault_with(
&self,
Expand All @@ -382,14 +383,24 @@ impl PyRRCache {

let inner = self.0.get();
let shared = inner.shared();

{
let mut policy = inner.policy();

if let Some(x) = policy.get(py, &key)? {
return Ok(x.value().clone_ref(py));
}
}

// `factory` is Python code: a GC pass inside it would deadlock on `__traverse__`
let default_object = factory.call0(py)?;

let mut policy = inner.policy();

if let Some(x) = policy.get(py, &key)? {
return Ok(x.value().clone_ref(py));
}

let default_object = factory.call0(py)?;

let handle = rrpolicy::Handle::with_precomputed_hash_key(
py,
shared.getsizeof(),
Expand Down
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