• Dominik Inführ's avatar
    [heap] Support multiple clients in shared GC · 90a9d6cb
    Dominik Inführ authored
    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: 's avatarJakob Gruber <jgruber@chromium.org>
    Reviewed-by: 's avatarMichael Lippautz <mlippautz@chromium.org>
    Cr-Commit-Position: refs/heads/main@{#77812}
    90a9d6cb
safepoint.cc 9.3 KB