This CL implements MemoryAllocator::LookupChunkContainingAddress, which
will be used for conservative stack scanning. The method determines
whether an address that may be an inner pointer is contained in some
allocated (normal or large) page. To achieve this, the CL introduces a
page database in the memory allocator.
Bug: v8:12851
Change-Id: I8b719a5f1b6e6b374ccf0666c91c2341c5f9856a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3784986
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Nikolaos Papaspyrou <nikolaos@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82004}
This CL refactors the mechanism for testing the implementation of inner
pointer resolution using the marking bitmap. It allows for more than one
page, where objects can be allocated. It also keeps a list of allocated
objects that are automatically tested.
Bug: v8:12851
Change-Id: I470dc1154aca1ebc3d8526872717747829f83396
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3784605
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Nikolaos Papaspyrou <nikolaos@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81952}
We will provide a replacement for raw pointers in future which should
only be used by backing stores. Any other callsite must go through
Trace(BasicMember<>).
Bug: v8:13089
Change-Id: Ibdae439b44ad94bd7af2532855be941c5334db99
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3772328
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81833}
Thread through compressed pointer into write barrier to allow to delay
compression after checking whether a write barrier is actually needed.
Change-Id: If7e6cbb69a57cc9aeeb551c11f685bace4e56c4c
Bug: chromium:1325007
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3769826
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81816}
This CL fixes a bug in the units of the reported metrics for
V8.GC.Cycle.MainThread.Full.Incremental.Mark (ms instead of us).
It also reports incremental marking/sweeping metrics (both for the
unified heap and the C++ managed heap) only when incremental
marking/sweeping were used; otherwise, no zero values are reported.
Bug: chromium:1154636
Bug: chromium:1343507
Change-Id: Ibc0103ea62fa0eeb5f7184280c8514e99a5c21a3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3768502
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Nikolaos Papaspyrou <nikolaos@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81803}
- Avoid adding an Invalid type that can never be reached during
traversal;
- Expose class names as object names;
Bug: chromium:1321620
Change-Id: Ie3d9f78d97703535ecf67d56235d564ab6a9a7e8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3763866
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81758}
This CL refactors the implementation of inner pointer resolution, based
on the marking bitmap. MarkCompactCollector::FindBasePtrForMarking has
most of its code that processes the marking bitmap moved to a utility
function FindPreviousObjectForConservativeMarking, which iterates
backwards to find the closest previous object on the page that has been
marked.
Bug: v8:12851
Change-Id: I980ac5712d8b1df792196d77edb9526ca2e13e2c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3758227
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Nikolaos Papaspyrou <nikolaos@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81750}
As sandboxed pointers are now default-enabled when the sandbox is
enabled, it is no longer possible to deactivate the sandbox at runtime.
This CL therefore removes all the logic that was required to support a
sandbox that could be disabled at runtime, moves the initialization of
the sandbox into V8::Initialize, and deprecates V8::InitializeSandbox.
This change also makes the sandbox initialization deterministic if
FLAG_random_seed is supplied.
Bug: v8:10391
Change-Id: Ibd49f7c251b7c58c642f18a551ecc2c391740970
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3762583
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81746}
The operator with raw pointer allows us to avoid Member decompression,
which is more expensive than compression. It's also quite frequently
called (e.g. in HeapHashSet::find()).
The existing operator
template <...>
bool operator==(const Member<T1>&, const Member<T2>&);
was not called for
GCed* raw = ...;
member == raw;
because the compiler wouldn't deduce `T2` in `const Member<T2>` as
`GCed` when the initializer expression `raw` is of different type
(`GCed*`).
Bug: chromium:1325007
Change-Id: Ie1ee12bad28081c66f4e08a146467fd7c040bb70
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3757344
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81702}
GCInfoTable is a process-global table storing Oilpan type information.
Table operations may fail in OOM scenarios which were previously just
caught in regular CHECKs. Change to use a global OOM handler that is set
up to use V8's handler.
Bug: chromium:1283199
Change-Id: Id33263ef7cd4028d60a071f5ab3b165e59ac9593
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3745368
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81540}
MinorMC maintained a separate marking state to support interleaved GCs.
Since MinorMC now assumes that interleaving is not possible, MinorMC can
use the same marking state as the full GC.
Bug: v8:12612
Change-Id: Ibeb7df2eb24e448f811b497c9d16b3b132f87ec2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3735163
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81468}
Fix some final gcc warnings:
* Manually roll googletest to get the fix in:
https://crrev.com/d5ad28dbe14fca51038fb8c7610f11602b98f682
* Remove some anonymous namespaces in tests because the types in those
anonymous namespaces ended up being visible in non-anonymous
classes.
* Fix a RVO breaking std::move.
* Change some known-too-short strncpys into memcpys
Bug: chromium:1307180
Change-Id: I0f64512f77655f3740fc297bbb2087e6c039f7f3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3735122
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81436}
This reverts commit 543acf345a.
Reason for revert: https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Mac%20-%20arm64%20-%20release/10365/overview
Original change's description:
> cppgc: Minor fix in cppgc efficiency calculation
>
> Efficiency calculation (freed bytes over GC duration) assumes that the
> duration of the GC is non zero. However, if the clock resolution is
> not small enough and the entire GC is very short, the timed value
> appears to be zero. This leads to NaN values showing in metrics and
> CHECKs failing. This CL fixes the issue.
>
> Bug: chromium:1338256
> Change-Id: I1dbc52072fcde3411aa38fa0c11da25afd107ca8
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3714356
> Reviewed-by: Omer Katz <omerkatz@chromium.org>
> Commit-Queue: Nikolaos Papaspyrou <nikolaos@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#81329}
Bug: chromium:1338256
Change-Id: Ie9a23651494fc28a11bb59485a9812ee1a7cff48
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3721697
Commit-Queue: Nico Hartmann <nicohartmann@chromium.org>
Owners-Override: Nico Hartmann <nicohartmann@chromium.org>
Auto-Submit: Nico Hartmann <nicohartmann@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#81331}
Efficiency calculation (freed bytes over GC duration) assumes that the
duration of the GC is non zero. However, if the clock resolution is
not small enough and the entire GC is very short, the timed value
appears to be zero. This leads to NaN values showing in metrics and
CHECKs failing. This CL fixes the issue.
Bug: chromium:1338256
Change-Id: I1dbc52072fcde3411aa38fa0c11da25afd107ca8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3714356
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Nikolaos Papaspyrou <nikolaos@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81329}
Creates a feature (flag): transition from Done -> Wait
schedules a timer after 30s instead of 8s.
In local benchmark, this reduces by 50% cpu time spent doing
incremental marking and sweeping.
Bug: chromium:1330940
Change-Id: Iff9121243b88d0ed87d0b921e285ece52a83eaa9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3696168
Commit-Queue: Etienne Pierre-Doray <etiennep@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81283}
Remove finalization step of incremental marking. The step was
historically used to process embedder/weak work on the main thread
before invoking the atomic pause. Remove the infrastructure as the
step is not needed anymore and actually required a safepoint.
Change-Id: I208767bbac3d9a06a0b3c67aa9779f8a5fa07328
Bug: v8:12775
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3702801
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81234}
This reverts commit 8325f86df3.
Reason for revert: Speculative revert for chromium:1336850.
Original change's description:
> [heap] Sweep code pages on the background thread
>
> We already make code pages writable & executable for concurrent
> Sparkplug. We can use the same mechanism for sweeping of code pages on
> the background thread, instead of scheduling incremental tasks on the
> main thread. This allows us to remove almost all special
> handling for code pages in the sweeper and allows us to off-load more
> work from the main thread.
>
> Bug: v8:12967
> Change-Id: Idb8e9f8e2eadbec26a386f2de683a80087f671f3
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695557
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#81139}
Bug: v8:12967, chromium:1336850
Change-Id: I1fb775892c2679984221efa7ceb682800c88cb2f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3707274
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81213}
The CL fixes PMF regressions that happend after increasing
the AgeTable size.
Bug: chromium:1336529
Change-Id: If1f099b43bfcb3a8c7dd4a1c229fcb08735eb744
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3707098
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81180}
We already make code pages writable & executable for concurrent
Sparkplug. We can use the same mechanism for sweeping of code pages on
the background thread, instead of scheduling incremental tasks on the
main thread. This allows us to remove almost all special
handling for code pages in the sweeper and allows us to off-load more
work from the main thread.
Bug: v8:12967
Change-Id: Idb8e9f8e2eadbec26a386f2de683a80087f671f3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695557
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81139}
We don't need to reset the entire age table, but merely the pages that
are known to contain young objects. This must improve memory use with
generational GC enabled.
The CL is a prerequisite for another CL that'll increase the size of
the age-table.
Bug: chromium:1029379
Change-Id: Ibb5b607af20380c3936b7396b3d9767f6f17c44b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695268
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81106}
Currently, PageAllocator assumes that FreePages(start, size) will always
be called on the same region that was passed to AllocatePages(start,
size). This assumption is made in:
1) leak-sanitizer (LsanPageAllocator) that checks it explicitly,
2) on Windows, FreePages() calls VirtualFree() with zero-size and
MEM_RELEASE, which causes the entire reservation to be freed.
The CL temporarily fixes the bot failures just by holding the unneeded
half and adds a TODO to return the unneded part back to the OS.
Bug: chromium:1325007
Change-Id: I2bd878876d43d693cf2138020f410ffe1615b4e9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695363
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81059}
Compaction currently considers only backing store pointers as slots and
those are uncompressed. The CL fixes the tests to use raw pointers
instead of Members.
Bug: chromium:1325007
Change-Id: I2ddfffeeab396552bb7cf31b2bd8502ebc2921fb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695590
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81056}
The CL does the following:
1) Globalizes CagedHeap for all HeapBases;
2) Adds the global variable representing the cage base;
3) Changes all write-barriers to use this global variable for value/slot
checks;
4) Removes no longer needed functionality introduced in previous CLs.
Bug: v8:12231
Change-Id: I281a7b0bf67e349c988486fc2d43ec6d703fd292
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3688050
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81027}
The CL splits the Oilpan giga-cage in two 2GB reservations: one for
normal pages and the other for large ones. The split enables fast
page-header lookup (assuming most objects reside on normal pages), which
is needed for:
1) the young generation project, where the remembered set will move to
pages;
2) the shared-cage project, to find HeapBase* from page-headers.
Bug: v8:12231, chromium:1029379
Change-Id: I4ae9e8a75a307ed0dff9a2ec4f1247b80e17ebd9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3688519
Auto-Submit: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80950}
This CL introduces the following changes to the experimental
implementation of the object start bitmap, that is evaluated as
a mechanism for resolving inner pointers (behind the flag
v8_enable_conservative_stack_scanning):
- Manually iterate through page objects, instead of using the
PagedSpaceObjectIterator, for performance (avoid calling
MakeHeapIterable all the time) and to simplify the handling
of filler objects.
- Clear bits when reusing evacuated pages of the new space.
- Use the cage base to iterate correctly through code objects.
- Introduce a method for verifying the validity of the object
start bitmap.
- Minor fixes, additional checks and cleanup.
Bug: v8:12851
Change-Id: I245937ffe6f4b53c4c2dcf5126e8836aec4dc79e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3675099
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Commit-Queue: Nikolaos Papaspyrou <nikolaos@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80869}
Due to collections with inlined storage, Oilpan still supports on-stack
Members, which are always compressed if pointer compression is enabled.
This CL scans halfwords (together with full words) on stack to find
potential pointers. Since on-heap pointers can only be compressed and
in-construction objects always reside on heap, only halfwords need to be
scanned for them.
The alternative potential followup approaches:
1) Use a separate uncompressed type for pointer in inlined collections;
2) Dynamically register regions of stack containing compressed pointers.
Bug: chromium:1325007
Change-Id: Ia706fd8e7383d30aff11f4014faa9edd3d289a55
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644959
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80747}
This CL adds to the existing experimental implementation of the
object start bitmap, that is evaluated as a mechanism for resolving
inner pointers (behind the flag v8_enable_conservative_stack_scanning).
It fixes method ObjectStartBitmap::FindBasePtr to ensure that the
correct base pointer is returned, even if the bitmap is not fully
populated (e.g., with object evacuation or inline object allocation).
This method now recalculates the part of the bitmap that is
required for returning the correct result, by iterating through
objects of the page. A special constructor has been introduced to the
PagedSpaceObjectIterator for this purpose.
It also moves the existing inline methods of ObjectStartBitmap to a
new -inl.h header file, to avoid circular dependencies.
Bug: v8:12851
Change-Id: Iabd0df020bee3bb63ef9d4888591b25d24d79dd9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3641179
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Nikolaos Papaspyrou <nikolaos@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80538}
This is more consistent with similar features, for example
V8_ENABLE_WEBASSEMBLY or V8_ENABLE_MAGLEV.
Drive-by: remove V8_SANDBOX_IS_AVAILABLE as it's no longer needed.
Bug: v8:10391
Change-Id: I8658c5b0c331a4c73892737083b2c2f9b8f84056
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647355
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Auto-Submit: Samuel Groß <saelo@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80530}
Now that we require C++17 support, we can just use the standard
static_assert without message, instead of our STATIC_ASSERT macro.
R=leszeks@chromium.org
Bug: v8:12425
Change-Id: I1d4e39c310b533bcd3a4af33d027827e6c083afe
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647353
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80524}
With this CL, the decompression simply becomes:
movsxd rax, edi
add rax, rax
and rax, qword ptr fs:[base@TPOFF]
Bug: chromium:1325007
Change-Id: I931e4e667a9b9697671bccf14575420f8cb705e8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3629871
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80521}
With caged heap enabled, we can halve Member<> by storing only the least
significant half. The base of the heap is stored in a thread local
variable. The feature has therefore an implication that only single heap
is allowed per thread.
The feature is gated by the new GN arg:
cppgc_enable_pointer_compression.
Bug: chromium:1325007
Change-Id: Ic7f1ecb7b9ded57caad63d95bbc8e8ad6ad65031
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2739979
Reviewed-by: Almothana Athamneh <almuthanna@chromium.org>
Commit-Queue: Almothana Athamneh <almuthanna@chromium.org>
Commit-Queue: Tamer Tas <tmrts@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Tamer Tas <tmrts@chromium.org>
Auto-Submit: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80518}
Many uses of "volatile" are deprecated in C++20 because they don't
actually do anything. Remove "volatile" in these cases.
Bug: chromium:1284275
Change-Id: I64a3989d73f25e0cd933375dd6fa0b3f2b3acb54
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3630343
Auto-Submit: Peter Kasting <pkasting@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Commit-Queue: Nico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80428}
Allocation granularity (8 bytes on 64bit platforms) is already subsumed
by whatever range size we choose.
Bug: chromium:1029379
Change-Id: Iab95e6f36955c9ffbbe9ea0c98cb9d1f8dd0337b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3629869
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Auto-Submit: Anton Bikineev <bikineev@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80415}
- Repurpose flag `treat_global_objects_as_roots` when taking a heap
snapshot for toggling whether internals should be exposed (to
`hide_internals`).
- Use the toggle in creating heap snapshots for exposing class names
as object names for C++ objects that have not explicitly been given a
name.
Change-Id: I77d71babfdfe53269964fe81ed985037a431c28b
Bug: chromium:1321620
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3623740
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80391}
Before this CL, the heap object name of unnamed objects(those not
inheriting from NameProvider) would be solely determined by whether the
build-time configuration cppgc_enable_object_names is enabled.
This patch adds a way to override that value at runtime. This is
useful for preserving default behavior with custom builds but at the
same time allow them to still enable the feature.
Bug: chromium:1321620
Change-Id: I3aa06db15e58d9ba9773be6797572f17f007e9ee
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3620279
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80338}
This fixes:
runtime error: upcast of misaligned address 0x000000000001
for type 'cppgc::internal::(anonymous namespace)::SimpleGCed<64>', which
requires 8 byte alignment
Bug: chromium:1029379
Change-Id: Id03ce022e72fc07a18c171d4cf5e42f50cb684f1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3622918
Auto-Submit: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80332}
The CL prepares the sources and the tests for enabling
cppgc_enable_young_generation by default. The static initializer
in YoungGenerationEnabler (due to v8::base::Mutex) changed to be lazy.
The tests are now checking the runtime flag.
Bug: chromium:1029379
Change-Id: I1497a3dd2b8d62c1acd48496821f07324b7944d5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3616726
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Auto-Submit: Anton Bikineev <bikineev@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80304}
The CL uses the different scheme to enable the generational barrier. The
separate global counter (is_enabled_) keeps track of the number of heaps
that enable generational GC. If at least one of the heaps enables the
generational GC, the counter will enable the write barrier. Technically,
the counter could be merged with WriteBarrier::is_enabled_, but having a
separate variable allows us to keep DCHECKs if generational barrier is
enabled.
Bug: chromium:1029379
Change-Id: Iafaa76f96acb18a73f8bde7231434e68c04cb683
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3616518
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80281}
The CL introduces a new option --cppgc-young-generation. This option
can't be enabled statically, because V8 options are parsed after heap
initialization. The CL changes minor GC so that it can be enabled
dynamically. The way it works is as follows:
- the user calls YoungGenerationEnabler::Enable();
- a heap checks in the next atomic pause whether the flag was enabled;
- if so, the heap enables young generation for itself.
To avoid barrier regressions without young-generation enabled, the CL changes the meaning of the global flag is-any-incremental-or-concurrent-marking to is-barrier-enabled.
The runtime option would enable us to test young generation on try-
and performance-bots.
Bug: chromium:1029379
Change-Id: I664cccdcd208225ffcbf9901f1284b56d088c5c3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3607993
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80274}
This is a reland of commit 9d31f8663a
There were issues with --future flag implications on M1.
Original change's description:
> [rwx][mac] Support fast W^X permission switching on Apple Silicon (M1)
>
> ... for V8 code space. The feature is currently disabled.
>
> In order to use fast W^X permission switching we must allocate
> executable pages with readable writable executable permissions (RWX).
> However, MacOS on ARM64 ("Apple M1"/Apple Silicon) prohibits further
> permission changing of RWX memory pages. This means that the code page
> headers must be allocated with RWX permissions too because otherwise
> it wouldn't be possible to allocate a large code page over the freed
> regular code page and vice versa.
>
> When enabled, the new machinery works as follows:
>
> 1) when memory region is reserved for allocating executable pages, the
> whole region is committed with RWX permissions and then decommitted,
> 2) since reconfiguration of RWX page permissions is not allowed on
> MacOS on ARM64 ("Apple M1"/Apple Silicon), there must be no attempts
> to change them,
> 3) the request to set RWX permissions in the executable page region
> just recommits the pages without changing permissions (see (1), they
> were already allocated as RWX and then discarded),
> 4) in order to make executable pages inaccessible one must use
> OS::DiscardSystemPages() instead of OS::DecommitPages() or
> setting permissions to kNoAccess because the latter two are not
> allowed by the MacOS (see (2)).
> 5) since code space page headers are allocated as RWX pages it's also
> necessary to switch between W^X modes when updating the data in the
> page headers (i.e. when marking, updating stats, wiring pages in
> lists, etc.). The new CodePageHeaderModificationScope class is used
> in the respective places. On unrelated configurations it's a no-op.
>
> The fast permission switching can't be used for V8 configuration with
> enabled pointer compression and disabled external code space because
> a) the pointer compression cage has to be reserved with MAP_JIT flag
> which is too expensive,
> b) in case of shared pointer compression cage if the code range will
> be deleted while the cage is still alive then attempt to configure
> permissions of pages that were previously set to RWX will fail.
>
> This also CL extends the unmapper unit tests with permissions tracking
> for discarded pages.
>
> Bug: v8:12797
> Change-Id: Idb28cbc481306477589eee9962d2e75167d87c61
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3579303
> Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
> Reviewed-by: Clemens Backes <clemensb@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#80238}
Bug: v8:12797
Change-Id: I0fe86666f31bad37d7074e217555c95900d2afba
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3610433
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80259}
For some reason the compiler was optimizing away the reference to the
object in WeakContainerTest.ConservativeGCTracesWeakContainer and thus
not finding it conservatively.
This CL revises the tests such that the compiler is no longer able to
optimize references away.
Bug: v8:12824
Change-Id: Ie598a1cf1124c2983a6c61fd4e990734d36f5832
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3610627
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80257}
This reverts commit 9d31f8663a.
Reason for revert: crashes on Mac/arm64 bots:
https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Mac%20-%20arm64%20-%20debug/5923/overview
Original change's description:
> [rwx][mac] Support fast W^X permission switching on Apple Silicon (M1)
>
> ... for V8 code space. The feature is currently disabled.
>
> In order to use fast W^X permission switching we must allocate
> executable pages with readable writable executable permissions (RWX).
> However, MacOS on ARM64 ("Apple M1"/Apple Silicon) prohibits further
> permission changing of RWX memory pages. This means that the code page
> headers must be allocated with RWX permissions too because otherwise
> it wouldn't be possible to allocate a large code page over the freed
> regular code page and vice versa.
>
> When enabled, the new machinery works as follows:
>
> 1) when memory region is reserved for allocating executable pages, the
> whole region is committed with RWX permissions and then decommitted,
> 2) since reconfiguration of RWX page permissions is not allowed on
> MacOS on ARM64 ("Apple M1"/Apple Silicon), there must be no attempts
> to change them,
> 3) the request to set RWX permissions in the executable page region
> just recommits the pages without changing permissions (see (1), they
> were already allocated as RWX and then discarded),
> 4) in order to make executable pages inaccessible one must use
> OS::DiscardSystemPages() instead of OS::DecommitPages() or
> setting permissions to kNoAccess because the latter two are not
> allowed by the MacOS (see (2)).
> 5) since code space page headers are allocated as RWX pages it's also
> necessary to switch between W^X modes when updating the data in the
> page headers (i.e. when marking, updating stats, wiring pages in
> lists, etc.). The new CodePageHeaderModificationScope class is used
> in the respective places. On unrelated configurations it's a no-op.
>
> The fast permission switching can't be used for V8 configuration with
> enabled pointer compression and disabled external code space because
> a) the pointer compression cage has to be reserved with MAP_JIT flag
> which is too expensive,
> b) in case of shared pointer compression cage if the code range will
> be deleted while the cage is still alive then attempt to configure
> permissions of pages that were previously set to RWX will fail.
>
> This also CL extends the unmapper unit tests with permissions tracking
> for discarded pages.
>
> Bug: v8:12797
> Change-Id: Idb28cbc481306477589eee9962d2e75167d87c61
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3579303
> Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
> Reviewed-by: Clemens Backes <clemensb@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#80238}
Bug: v8:12797
Change-Id: Ic07948e036db36326d464a2a901d052aa060a406
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3611665
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Auto-Submit: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80239}
... for V8 code space. The feature is currently disabled.
In order to use fast W^X permission switching we must allocate
executable pages with readable writable executable permissions (RWX).
However, MacOS on ARM64 ("Apple M1"/Apple Silicon) prohibits further
permission changing of RWX memory pages. This means that the code page
headers must be allocated with RWX permissions too because otherwise
it wouldn't be possible to allocate a large code page over the freed
regular code page and vice versa.
When enabled, the new machinery works as follows:
1) when memory region is reserved for allocating executable pages, the
whole region is committed with RWX permissions and then decommitted,
2) since reconfiguration of RWX page permissions is not allowed on
MacOS on ARM64 ("Apple M1"/Apple Silicon), there must be no attempts
to change them,
3) the request to set RWX permissions in the executable page region
just recommits the pages without changing permissions (see (1), they
were already allocated as RWX and then discarded),
4) in order to make executable pages inaccessible one must use
OS::DiscardSystemPages() instead of OS::DecommitPages() or
setting permissions to kNoAccess because the latter two are not
allowed by the MacOS (see (2)).
5) since code space page headers are allocated as RWX pages it's also
necessary to switch between W^X modes when updating the data in the
page headers (i.e. when marking, updating stats, wiring pages in
lists, etc.). The new CodePageHeaderModificationScope class is used
in the respective places. On unrelated configurations it's a no-op.
The fast permission switching can't be used for V8 configuration with
enabled pointer compression and disabled external code space because
a) the pointer compression cage has to be reserved with MAP_JIT flag
which is too expensive,
b) in case of shared pointer compression cage if the code range will
be deleted while the cage is still alive then attempt to configure
permissions of pages that were previously set to RWX will fail.
This also CL extends the unmapper unit tests with permissions tracking
for discarded pages.
Bug: v8:12797
Change-Id: Idb28cbc481306477589eee9962d2e75167d87c61
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3579303
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80238}
