tree e478048e5ecb5c8d78f9821c4dcd133232cb78b7
parent f94aa6e329b946d983755ce7abe69c8c6434aa12
author Liam Appelbe <liama@google.com> 1545157870 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> 1545157870 +0000

Make capacity check and usage increase atomic.

The fiddly part of this is that the current flow is: check
capacity, allocate page, increase usage (but only if page
allocation was successful). So the idea of this CL is to
increase the usage optimistically, then decrease it if the
page allocation fails.

Closes https://github.com/dart-lang/sdk/issues/27413

Bug: https://github.com/dart-lang/sdk/issues/27413
Change-Id: I97ccf3c5a449dc377b8748a73ff4fcffe6d07f2b
Reviewed-on: https://dart-review.googlesource.com/c/86943
Commit-Queue: Liam Appelbe <liama@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>