• Dominik Inführ's avatar
    Reland "[heap] Support multiple clients in shared GC" · 2c88cec4
    Dominik Inführ authored
    This is a reland of 90a9d6cb
    
    The original CL got reverted because of two different issues:
    
    * The DCHECK failure on AllowGarbageCollection::IsAllowed() got fixed
      in https://crrev.com/c/3289625.
    * The crash with the incremental marking job were because of a nested
      GC started from a SafepointScope. This CL adds IgnoreLocalGCRequests
      scopes to SafepointScopes in src/heap.
    
    In addition this CL prevents shared GCs during isolate deserialization
    by locking the clients_mutex_ until the isolate is fully deserialized.
    The original GC used a DisallowSafepoints scope to prevent shared GCs
    from interrupting isolate deserialization.
    
    Original change's description:
    > [heap] Support multiple clients in shared GC
    >
    > Add support for safepointing multiple isolates as described in the
    > design doc (link is below). A safepoint across multiple isolates is
    > considered a global safepoint to distinguish it from regular safepoints.
    >
    > The basic idea behind the implementation is that we reach a
    > safepoint for each client. What's new is that now also main threads
    > need to participate in the safepointing protocol and need to give up
    > control in time. The slow paths of Park(), Unpark() and Safepoint() on
    > the main thread need to be adjusted for this reason as well.
    >
    > This CL introduces GlobalSafepoint and GlobalSafepointScope to mirror
    > IsolateSafepoint and IsolateSafepointScope.
    >
    > This CL adds the type IgnoreLocalGCRequests, it is used to prevent
    > Park() and Unpark() from honoring the request from background threads
    > to perform a local GC. This is used heap-internally to not have GCs
    > (or even nested GCs) in certain locations. E.g. when initiating a
    > safepoint to perform a GC we don't want a "recursive" GC to occur.
    >
    > Design doc: https://docs.google.com/document/d/1y6C9zAACEr0sBYMIYk3YpXosnkF3Ak4CEuWJu1-3zXs/edit?usp=sharing
    >
    > Bug: v8:11708
    > Change-Id: I5aca8f5f24873279271a53be3bb093fc92a1a1eb
    > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3009224
    > Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
    > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
    > Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
    > Cr-Commit-Position: refs/heads/main@{#77812}
    
    Bug: v8:11708, v8:12375, v8:12377
    Change-Id: I9d1af6fbc06a3a8b6f216ec5e9027665ad071809
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3283067
    Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
    Reviewed-by: 's avatarMichael Lippautz <mlippautz@chromium.org>
    Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
    Cr-Commit-Position: refs/heads/main@{#78013}
    2c88cec4
safepoint.cc 9.75 KB