[pbs-devel] applied: [PATCH proxmox-backup] pbs-tools: LruCache: implement Drop

[Wolfgang Bumiller <w.bumiller@proxmox.com>]

applied, thanks

On Thu, Jan 20, 2022 at 11:16:08AM +0100, Dominik Csapak wrote:
> this fixes the leaked memory for the cache, as we had only pointers
> in the map/list which were freed, not the underlying chunks
> 
> moves the 'clear' implementation out of the trait bounds so that
> Drop can reuse it
> 
> this is used e.g. for file download from a pxar
> 
> Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
> ---
>  pbs-tools/src/lru_cache.rs | 24 ++++++++++++++++--------
>  1 file changed, 16 insertions(+), 8 deletions(-)
> 
> diff --git a/pbs-tools/src/lru_cache.rs b/pbs-tools/src/lru_cache.rs
> index b1c0c6ac..fbd7673a 100644
> --- a/pbs-tools/src/lru_cache.rs
> +++ b/pbs-tools/src/lru_cache.rs
> @@ -100,9 +100,25 @@ pub struct LruCache<K, V> {
>      _marker: PhantomData<Box<CacheNode<K, V>>>,
>  }
>  
> +impl<K, V> Drop for LruCache<K, V> {
> +    fn drop (&mut self) {
> +        self.clear();
> +    }
> +}
> +
>  // trivial: if our contents are Send, the whole cache is Send
>  unsafe impl<K: Send, V: Send> Send for LruCache<K, V> {}
>  
> +impl<K, V> LruCache<K, V> {
> +    /// Clear all the entries from the cache.
> +    pub fn clear(&mut self) {
> +        // This frees only the HashMap with the node pointers.
> +        self.map.clear();
> +        // This frees the actual nodes and resets the list head and tail.
> +        self.list.clear();
> +    }
> +}
> +
>  impl<K: std::cmp::Eq + std::hash::Hash + Copy, V> LruCache<K, V> {
>      /// Create LRU cache instance which holds up to `capacity` nodes at once.
>      pub fn new(capacity: usize) -> Self {
> @@ -115,14 +131,6 @@ impl<K: std::cmp::Eq + std::hash::Hash + Copy, V> LruCache<K, V> {
>          }
>      }
>  
> -    /// Clear all the entries from the cache.
> -    pub fn clear(&mut self) {
> -        // This frees only the HashMap with the node pointers.
> -        self.map.clear();
> -        // This frees the actual nodes and resets the list head and tail.
> -        self.list.clear();
> -    }
> -
>      /// Insert or update an entry identified by `key` with the given `value`.
>      /// This entry is placed as the most recently used node at the head.
>      pub fn insert(&mut self, key: K, value: V) {
> -- 
> 2.30.2