src: introduce custom smart pointers for BaseObjects
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Referring to `BaseObject` instances using standard C++ smart pointers can interfere with BaseObject’s own cleanup mechanisms (explicit delete, delete-on-GC and delete-on-cleanup). Introducing custom smart pointers allows referring to `BaseObject`s safely while keeping those mechanisms intact. Refs: nodejs/quic#141 Refs: nodejs/quic#149 Reviewed-By: James M Snell <jasnell@gmail.com>
Refs: nodejs/quic#141 Reviewed-By: James M Snell <jasnell@gmail.com>
This is no longer necessary now that the copyable `BaseObjectPtr` is available (as opposed to the only-movable `v8::Global`).
This allows keeping `BaseObjectPtr`s to `HandleWrap` instances. Previously, the pointer kept the `HandleWrap` object alive, leaving the Environment cleanup code that waits for the handle list to drain in a busy loop, because only the `HandleWrap` destructor removed the item from the list. Refs: nodejs/quic#165 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
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Referring to `BaseObject` instances using standard C++ smart pointers can interfere with BaseObject’s own cleanup mechanisms (explicit delete, delete-on-GC and delete-on-cleanup). Introducing custom smart pointers allows referring to `BaseObject`s safely while keeping those mechanisms intact. Refs: nodejs/quic#141 Refs: nodejs/quic#149 Reviewed-By: James M Snell <jasnell@gmail.com> PR-URL: #30374 Refs: nodejs/quic#165 Reviewed-By: David Carlier <devnexen@gmail.com>
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Refs: nodejs/quic#141 Reviewed-By: James M Snell <jasnell@gmail.com> PR-URL: #30374 Refs: nodejs/quic#149 Refs: nodejs/quic#165 Reviewed-By: David Carlier <devnexen@gmail.com>
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PR-URL: #30374 Refs: nodejs/quic#141 Refs: nodejs/quic#149 Refs: nodejs/quic#141 Refs: nodejs/quic#165 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: David Carlier <devnexen@gmail.com>
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This is no longer necessary now that the copyable `BaseObjectPtr` is available (as opposed to the only-movable `v8::Global`). PR-URL: #30374 Refs: nodejs/quic#141 Refs: nodejs/quic#149 Refs: nodejs/quic#141 Refs: nodejs/quic#165 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: David Carlier <devnexen@gmail.com>
addaleax
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This allows keeping `BaseObjectPtr`s to `HandleWrap` instances. Previously, the pointer kept the `HandleWrap` object alive, leaving the Environment cleanup code that waits for the handle list to drain in a busy loop, because only the `HandleWrap` destructor removed the item from the list. Refs: nodejs/quic#165 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com> PR-URL: #30374 Refs: nodejs/quic#141 Refs: nodejs/quic#149 Refs: nodejs/quic#141 Reviewed-By: David Carlier <devnexen@gmail.com>
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Landed in efce655...1317ac6 |
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@addaleax should this be backported or is this blocked on another PR that should be backported first? It does not land cleanly on our v13.x-staging currently. Please either update the labels accordingly or open a manual backport, thanks! |
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I think this should have an easier time landing after the V8 7.9 backport. |
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Referring to `BaseObject` instances using standard C++ smart pointers can interfere with BaseObject’s own cleanup mechanisms (explicit delete, delete-on-GC and delete-on-cleanup). Introducing custom smart pointers allows referring to `BaseObject`s safely while keeping those mechanisms intact. Refs: nodejs/quic#141 Refs: nodejs/quic#149 Reviewed-By: James M Snell <jasnell@gmail.com> PR-URL: #30374 Refs: nodejs/quic#165 Reviewed-By: David Carlier <devnexen@gmail.com>
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PR-URL: nodejs#30374 Refs: nodejs/quic#141 Refs: nodejs/quic#149 Refs: nodejs/quic#141 Refs: nodejs/quic#165 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: David Carlier <devnexen@gmail.com>
MylesBorins
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This is no longer necessary now that the copyable `BaseObjectPtr` is available (as opposed to the only-movable `v8::Global`). PR-URL: nodejs#30374 Refs: nodejs/quic#141 Refs: nodejs/quic#149 Refs: nodejs/quic#141 Refs: nodejs/quic#165 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: David Carlier <devnexen@gmail.com>
MylesBorins
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Apr 1, 2020
This allows keeping `BaseObjectPtr`s to `HandleWrap` instances. Previously, the pointer kept the `HandleWrap` object alive, leaving the Environment cleanup code that waits for the handle list to drain in a busy loop, because only the `HandleWrap` destructor removed the item from the list. Refs: nodejs/quic#165 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com> PR-URL: nodejs#30374 Refs: nodejs/quic#141 Refs: nodejs/quic#149 Refs: nodejs/quic#141 Reviewed-By: David Carlier <devnexen@gmail.com>
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This was overlooked in a489583. Refs: nodejs#30374 PR-URL: nodejs#30666 Fixes: nodejs#30643 Reviewed-By: Rich Trott <rtrott@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>
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This is in preparation for running native `SetImmediate()` callbacks during shutdown. PR-URL: nodejs#30666 Fixes: nodejs#30643 Refs: nodejs#30374 Reviewed-By: Rich Trott <rtrott@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>
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Guard against running `SetImmediate()` from the destructor. The object will not be alive or usable in the callback, so it does not make sense to attempt to schedule the `SetImmediate()`. PR-URL: nodejs#30666 Fixes: nodejs#30643 Refs: nodejs#30374 Reviewed-By: Rich Trott <rtrott@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>
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This can be necessary, because some parts of the Node.js code base perform cleanup operations in the Immediate callbacks, e.g. HTTP/2. This resolves flakiness in an HTTP/2 test that failed when a `SetImmediate()` callback was not run or destroyed before the `Environment` destructor started, because that callback held a strong reference to the `Http2Session` object and the expectation was that no such objects exist once the `Environment` constructor starts. Another, slightly more direct, alternative would have been to clear the immediate queue rather than to run it. However, this approach seems to make more sense as code generally assumes that the `SetImmediate()` callback will always run; For example, N-API uses an immediate callback to call buffer finalization callbacks. Unref’ed immediates are skipped, as the expectation is generally that they may not run anyway. Fixes: nodejs#30643 PR-URL: nodejs#30666 Refs: nodejs#30374 Reviewed-By: Rich Trott <rtrott@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>
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Apr 1, 2020
Fix the condition for deleting the underlying data pointed to by a `BaseObjectWeakPtr`, which erroneously skipped that deletion when `ptr->get()` was `nullptr`. This fixes a memory leak reported by some of the tests. Refs: nodejs#30374 (comment) PR-URL: nodejs#32393 Reviewed-By: Matheus Marchini <mat@mmarchini.me> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
MylesBorins
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Apr 1, 2020
Referring to `BaseObject` instances using standard C++ smart pointers can interfere with BaseObject’s own cleanup mechanisms (explicit delete, delete-on-GC and delete-on-cleanup). Introducing custom smart pointers allows referring to `BaseObject`s safely while keeping those mechanisms intact. Refs: nodejs/quic#141 Refs: nodejs/quic#149 Reviewed-By: James M Snell <jasnell@gmail.com> Backport-PR-URL: #32301 PR-URL: #30374 Refs: nodejs/quic#165 Reviewed-By: David Carlier <devnexen@gmail.com>
MylesBorins
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Refs: nodejs/quic#141 Reviewed-By: James M Snell <jasnell@gmail.com> Backport-PR-URL: #32301 PR-URL: #30374 Refs: nodejs/quic#149 Refs: nodejs/quic#165 Reviewed-By: David Carlier <devnexen@gmail.com>
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Backport-PR-URL: #32301 PR-URL: #30374 Refs: nodejs/quic#141 Refs: nodejs/quic#149 Refs: nodejs/quic#141 Refs: nodejs/quic#165 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: David Carlier <devnexen@gmail.com>
MylesBorins
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Apr 1, 2020
This is no longer necessary now that the copyable `BaseObjectPtr` is available (as opposed to the only-movable `v8::Global`). Backport-PR-URL: #32301 PR-URL: #30374 Refs: nodejs/quic#141 Refs: nodejs/quic#149 Refs: nodejs/quic#141 Refs: nodejs/quic#165 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: David Carlier <devnexen@gmail.com>
MylesBorins
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that referenced
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Apr 1, 2020
This allows keeping `BaseObjectPtr`s to `HandleWrap` instances. Previously, the pointer kept the `HandleWrap` object alive, leaving the Environment cleanup code that waits for the handle list to drain in a busy loop, because only the `HandleWrap` destructor removed the item from the list. Refs: nodejs/quic#165 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com> Backport-PR-URL: #32301 PR-URL: #30374 Refs: nodejs/quic#141 Refs: nodejs/quic#149 Refs: nodejs/quic#141 Reviewed-By: David Carlier <devnexen@gmail.com>
MylesBorins
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Apr 1, 2020
MylesBorins
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Apr 1, 2020
MylesBorins
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Apr 1, 2020
Guard against running `SetImmediate()` from the destructor. The object will not be alive or usable in the callback, so it does not make sense to attempt to schedule the `SetImmediate()`. Backport-PR-URL: #32301 PR-URL: #30666 Fixes: #30643 Refs: #30374 Reviewed-By: Rich Trott <rtrott@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>
MylesBorins
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that referenced
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Apr 1, 2020
This can be necessary, because some parts of the Node.js code base perform cleanup operations in the Immediate callbacks, e.g. HTTP/2. This resolves flakiness in an HTTP/2 test that failed when a `SetImmediate()` callback was not run or destroyed before the `Environment` destructor started, because that callback held a strong reference to the `Http2Session` object and the expectation was that no such objects exist once the `Environment` constructor starts. Another, slightly more direct, alternative would have been to clear the immediate queue rather than to run it. However, this approach seems to make more sense as code generally assumes that the `SetImmediate()` callback will always run; For example, N-API uses an immediate callback to call buffer finalization callbacks. Unref’ed immediates are skipped, as the expectation is generally that they may not run anyway. Fixes: #30643 Backport-PR-URL: #32301 PR-URL: #30666 Refs: #30374 Reviewed-By: Rich Trott <rtrott@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>
MylesBorins
pushed a commit
that referenced
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Apr 1, 2020
Fix the condition for deleting the underlying data pointed to by a `BaseObjectWeakPtr`, which erroneously skipped that deletion when `ptr->get()` was `nullptr`. This fixes a memory leak reported by some of the tests. Refs: #30374 (comment) Backport-PR-URL: #32301 PR-URL: #32393 Reviewed-By: Matheus Marchini <mat@mmarchini.me> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
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Note: Some of the commits here are from https://github.com/nodejs/quic/, where this concept has proven useful so far.
src: introduce custom smart pointers for
BaseObjectsReferring to
BaseObjectinstances using standard C++ smart pointerscan interfere with BaseObject’s own cleanup mechanisms
(explicit delete, delete-on-GC and delete-on-cleanup).
Introducing custom smart pointers allows referring to
BaseObjectssafely while keeping those mechanisms intact.
Refs: nodejs/quic#141
Refs: nodejs/quic#149
Reviewed-By: James M Snell jasnell@gmail.com
http2: use custom BaseObject smart pointers
Refs: nodejs/quic#141
Reviewed-By: James M Snell jasnell@gmail.com
src: use BaseObjectPtr for keeping channel alive in dns bindings
src: remove keep alive option from SetImmediate()
This is no longer necessary now that the copyable
BaseObjectPtris available (as opposed to the only-movable
v8::Global).src: remove HandleWrap instances from list once closed
This allows keeping
BaseObjectPtrs toHandleWrapinstances.Previously, the pointer kept the
HandleWrapobject alive, leavingthe Environment cleanup code that waits for the handle list to drain
in a busy loop, because only the
HandleWrapdestructor removedthe item from the list.
Refs: nodejs/quic#165
Reviewed-By: James M Snell jasnell@gmail.com
Reviewed-By: Daniel Bevenius daniel.bevenius@gmail.com
Checklist
make -j4 test(UNIX), orvcbuild test(Windows) passes