> The methods `load()`, `unload()`, `isLoaded()`, and `force()` in 
> `MemorySegment` currently delegate to `ScopedMemoryAccess` through a set of 
> `@Scoped` methods, after which the implementation calls into 
> `java.nio.MappedMemoryUtils`. This means that, when a shared scope is closed 
> during a call to one of these methods, an exception can be installed at any 
> point during the execution of the util method.
> 
> The problem is that some parts of these methods are not able to handle such 
> exceptions being installed.
> 
> We've had some previous discussion about these methods not really needing to 
> be `@Scoped` in the first place, but instead being able to rely on paired 
> acquire/release of the session being accessed. This code is not as 
> performance critical compared to a scoped memory access, since we're doing a 
> native call any way.
> 
> To avoid issues with exceptions being installed in surprising places, this 
> patch switches the named methods to use acquire/release instead of being 
> `@Scoped`. This changes the behavior of these methods slightly: they now keep 
> the scope alive during the execution of the method. I've updated the doc, 
> borrowing from existing text in the `Linked::downcallHandle` docs, to explain 
> that a scope closure may now fail during the execution of one of these 
> methods.
> 
> Does this seem like the right tradeoff?
> 
> ---------
> - [x] I confirm that I make this contribution in accordance with the [OpenJDK 
> Interim AI Policy](https://openjdk.org/legal/ai).

Jorn Vernee has updated the pull request incrementally with two additional 
commits since the last revision:

 - tweak comment
 - Fix issue where release is called even when acquire completes abnormally

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/31918/files
  - new: https://git.openjdk.org/jdk/pull/31918/files/a72213fb..5ee9830b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=31918&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=31918&range=00-01

  Stats: 110 lines in 2 files changed: 98 ins; 12 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/31918.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/31918/head:pull/31918

PR: https://git.openjdk.org/jdk/pull/31918

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