- New CMake option MOBILEGL_BUILD_DISAGGREGATED (default OFF, plan B appendix B). ON appends the MG_Remote sources to SOURCE_FILES, puts 3rdparty/flatbuffers/include on the include path and defines MOBILEGL_BUILD_DISAGGREGATED=1. OFF compiles nothing from MG_Remote and adds no include path and no library, which is one of the two byte-level equalities plan B section 10.3 keeps: measured `nm --defined-only build-linux/libMobileGL.so | grep -ic MG_Remote` = 0 with the option OFF and 93 with it ON, with an identical ldd set in both configurations.
- The option forces itself OFF with message(WARNING) when 3rdparty/flatbuffers/include/flatbuffers/flatbuffers.h is missing, so a checkout without the submodule still configures and builds rather than failing a hundred lines later on a missing header.
- ITransport.h: SendFrame / ReceiveFrame / PeekFrameSize / ShareFd / ReceiveFd / Shutdown. ReceiveFrame's contract is the fix for a defect of the earlier branch: a destination buffer smaller than the pending message returns MOBILEGL_ERR_BUFFER_TOO_SMALL with the required size and KEEPS the message queued. The earlier transport failed the call and popped the message anyway, which wedges the stream permanently the first time a reader guesses a size wrong.
- Framing.h: [u32 'MGLF'][u32 len][payload], 64 MiB cap, validated on read. A bad magic or an oversized length latches the reader dead, is logged at ERROR and makes every later call return MOBILEGL_ERR_PROTOCOL_MISMATCH. This is the second inherited defect: Feat/CS-Delta-IPC's Framing.h:41-45 Feed() always returned OK and its header peek merely returned false, so a desynchronized stream became a silent permanent hang; its LocalSocketTransport.cpp:232-236 then allocated on the peer-supplied length with no cap. The magic is also byte-ordered so it reads "MGLF" on the wire, where the earlier constant spelled "FLGM".
- Ring.h/.cpp: RingControl exactly as the inherited design (plan B section 8.1 -> earlier section 6.2): two independent cursor triples (cmd and stage, each {head, appliedTail, retiredTail}), appliedSeq / submittedSeq / retiredSeq / completedFrameSerial / presentAckSerial, serverEpoch, ringGeneration, consumerParked, producerParked, eventRingFull, eventDropped. One 4096-byte page with each contended group on its own cache line, pinned by static_assert on size and alignment and by an offset test.
- The SPSC pair uses monotonic byte cursors and a power-of-two mask, so a torn read can never look like a valid earlier position. A record never straddles the wrap: the producer emits a kPad filler to the boundary, which is always a multiple of 8 and therefore always has room for a header. The producer reclaims against retiredTail rather than appliedTail, so the day the server borrows a ring slot into the GPU timeline (kRecBorrowSlot) it does not silently degrade to early recycling. HardDrainRing bumps ringGeneration only when the ring is quiesced, and leaves the cursors monotonic so cached offsets are recognisably stale.
- The consumer bounds-checks every record header before dispatch (8-aligned, at least a header, no larger than what the producer published, contiguous inside the mapping) and reports corruption to the caller instead of dispatching into undefined behaviour. That is the runtime half of the earlier section 6.3 discipline: SEG_CMD is written by another process, so a compile-time static_assert on record sizes proves nothing about what is in the mapping.
- Doorbell.h/.cpp: spin then park, both directions (earlier section 6.2a). CondVarDoorbell for inproc, SocketDoorbell for spawn (one byte, codes 0x01 ring-advanced and 0x02 watermark-advanced) - no futex, eventfd or named event anywhere. The lost-wakeup window is closed by ordering: the waiter stores its park flag seq_cst and then re-tests the condition, NotifyIfParked loads the same flag seq_cst after the watermark is published, so one of the two always sees the other. kDefaultSpinUs is 50, the MOBILEGL_IPC_SPIN_US default.
- ShmSegment.{h,cpp} + ShmSegmentPosix.cpp: memfd_create by raw syscall on desktop Linux (the glibc wrapper is too recent to rely on), ASharedMemory_create on Android (API 26; libc's memfd_create wrapper is API 30, above MobileGL's floor), shm_open + immediate shm_unlink as the fallback. Adopt() refuses a descriptor whose fstat size is smaller than the size the peer announced, so a short segment cannot turn every later offset into an out-of-bounds map. ShmSegmentWin32.cpp (CreateFileMappingW in Local\) is compile-guarded and untested - this project's Windows machine is not a correctness gate.
- The Android path is compile-verified, not just written: an arm64-v8a NDK build with the option ON links, ShmSegmentPosix.cpp.o carries an undefined ASharedMemory_create, and ShmSegmentWin32.cpp.o is empty there. That build is also what caught the missing <cstddef> in ShmSegment.h and Framing.h, where std::size_t / std::ptrdiff_t only resolved through a transitive include on the host sysroot.
- FdPassing.{h,cpp}: SCM_RIGHTS in the FIRST transport commit, as plan B section 8.1 demands, over a dedicated AF_UNIX SOCK_DGRAM socketpair rather than the control byte stream (message boundaries survive on every POSIX - SOCK_SEQPACKET does not exist on macOS - and ancillary data can never be split from its payload). The third inherited defect this replaces: Feat/CS-Delta-IPC deferred fd passing and hardcoded `out->fd = -1` in LocalSocketTransport.cpp:296, so on the only platform that matters its data plane could not move one byte between processes. MSG_CTRUNC, an unexpected descriptor count and a malformed sideband header all close every descriptor received before failing, and a too-small sideband buffer is refused before the recvmsg so a datagram is never half-consumed.
- InProcessTransport.{h,cpp}: two in-memory queues plus the condvar doorbell pair. It keeps the frame size cap so nothing that passes in inproc becomes illegal after the switch to spawn, hands descriptors over with dup() under the same ownership rule as SCM_RIGHTS, and lets a peer's queued messages be drained after Shutdown - usually the last one says why it is going away.
- Not done here on purpose: the MOBILEGL_IPC_* environment variables are parsed in ConfigLoader.cpp, which belongs to another P0 work package running in parallel; this commit only exposes the constants (kDefaultSpinUs, kMaxFramePayloadSize, FdPassing::kMaxSidebandBytes) so that plumbing has something to set.
- 3rdparty/flatbuffers submodule pinned to the latest release tag v25.12.19 (7e163021). The runtime is header-only, so only 3rdparty/flatbuffers/include is ever used and no library is linked; CMake never calls add_subdirectory on it and flatc is not in the build graph (plan B section 8.1, inheriting the earlier plan's section 7.1).
- MobileGL/MG_Remote/Protocol/protocol.fbs carries the CONTROL PLANE only: SegmentRef, Hello, Welcome, CapsSnapshot, DefaultFramebufferInfo, SurfaceOp, SurfaceReply, ResyncRequest, ResyncDone, AuxRequest, Fatal, LogLine, union CtrlMsg and the CtrlEnvelope root with a file_identifier. Hot-path records are FlatBuffers structs generated from MG_Pipe/PipeCalls.def in a later package and are deliberately absent here, so record numbering never churns.
- Two deviations from the earlier plan's section 7.1 sketch, both deliberate: (a) ProgramReflection is not a union member - plan B ships program artifacts inside the create_shader_state CSO blob (section 8.2), and union tags are wire values that may only ever be appended, so reserving a tag for a message that may never exist is worse than appending one later; (b) maxComputeWorkGroupCount/Size are vectors, not [int:3] - fixed-size arrays are legal only in FlatBuffers structs, never in tables.
- scripts/gen_protocol.py resolves flatc as MOBILEGL_FLATC_EXECUTABLE, otherwise builds the pinned flatc ONCE into <repo>/../flatc-build (override with MOBILEGL_FLATC_BUILD_DIR), outside the project build graph. A flatc found on PATH is deliberately refused and a version mismatch against the pinned runtime is a hard error: the generated header static_asserts FLATBUFFERS_VERSION, so a stray flatc either fails to compile or churns the committed file on every machine. The earlier branch did the opposite - Protocol/CMakeLists.txt:22-38 add_subdirectory'd the FlatBuffers tree with FLATBUFFERS_BUILD_FLATC=ON whenever MOBILEGL_FLATC_EXECUTABLE was unset, which is exactly the NDK trap it claimed to avoid (cross-compile an arm64 flatc, then run it on the host).
- protocol_generated.h is committed with the project source header prepended by the generator, so regeneration is byte-identical: verified by running gen_protocol.py twice and by perturbing the file and regenerating it back.
- Reuse from Feat/CS-Delta-IPC: MobileGL/Protocol/mg_protocol_base.h, kept as the shared C vocabulary (result codes, byte spans, shm region, id typedefs) and keeping the structSize-first versioning discipline that section 14.2 calls the answer to risk B-R10. Dropped from it: MobileGLObjectKind / MobileGLObjectScope / MobileGLObjectHandle - plan B never puts GL object identity on the wire (the frontend allocates {slot, generation} handles in MG_Pipe, section 4.2.1), so a second identity vocabulary would be a drift surface with no reader. Added MOBILEGL_ERR_BUFFER_TOO_SMALL as an append-only code for the receive contract.
- VulkanRenderer::CurrentXfbCounterSlot keyed m_xfbCounterSlotByObject on
GetBoundTransformFeedbackName(). glGenTransformFeedbacks hands a deleted name
straight back (IndexGenerator is LIFO) and nothing ever removed a map entry, so
a transform feedback object created on a recycled name was served the DEAD
object's counter group - and with it that group's m_xfbCountersValid and
m_xfbLastSeenGeneration entries, which are the resume/fresh decision for
vkCmdBeginTransformFeedbackEXT. This is D21 in plan B v2 4.7.3, the one entry
in that table whose today-key "guards nothing", and 10.4-5 asks for it to land
on dev on its own - hence this separate commit, kept in files no other commit
on this branch touches so the cherry-pick applies unaided.
- Frontend: TransformFeedbackObjectState gains a never-reused `lifetimeId`
through a default member initialiser, so every route into existence
(operator[] materialisation, `= {}` in GenTransformFeedbackNames and
CreateTransformFeedbackObject) mints a fresh one and a recycled name cannot
carry the dead object's id back. The allocator is the same shape as
BufferObject::AllocateLifetimeId (atomic, starts at 1 so a zeroed backend slot
is never a live object).
- The bound object's id is mirrored in m_boundTransformFeedbackLifetimeId,
refreshed by RestoreBoundTransformFeedbackState - which every bind, and the
revert that deleting the bound object performs, goes through - and seeded for
the default object by the GLContext constructor. GetBoundTransformFeedback
LifetimeId is therefore a const load. Reading it through operator[] instead
would have been an INSERT on the per-draw path, and UnorderedMap is
ska::flat_hash_map, whose rehash invalidates every reference into the
container, not just its iterators.
- Backend: the UnorderedMap is replaced by a fixed 16-entry owner table, which
fixes the second half of the same defect - the map was keyed on a value that
recycles yet was never pruned, so it grew for the life of the context. With
lifetime ids as keys a map would have grown without bound instead, so the
bounded table is required, not cosmetic.
- Slot exhaustion: past sixteen owners a group has to be taken over, and the
victim is chosen among owners with NO OPEN SPAN, which
GLContext::HasOpenTransformFeedbackSpan answers; an identity no live object
carries any more answers false, and that is what lets a dead owner's group
come back. Least-recently-used ALONE would have been exactly the wrong rule:
GL only permits another object to capture while this one is PAUSED, so the
paused span these groups exist to protect is by construction the least
recently used entry, and an LRU takeover would reset the one resume offset
that still matters. LRU is now only the tie-break among reclaimable groups.
Sixteen genuinely open spans at once is reported (MGLOG_E_ONCE) rather than
resolved silently, because whatever is taken then restarts at offset 0.
- Not done, and why: the natural place to hand a group back is
glEndTransformFeedback, but registering DirectVulkan's EndTransformFeedback
table entry would flip the test FixupGsStripCaptureOrder makes of that same
pointer (GL_Drawing.cpp:1255) to decide whether the backend already captured
in GL's vertex order, silently disabling the geometry-stage strip fixup for
DirectVulkan. Giving that discriminator a name of its own is a separate
change; until then the no-open-span rule is what keeps the table honest.
- CurrentXfbCounterSlot asserts the identity is never 0. Zero is the free-slot
sentinel, so an identity of 0 would match every free slot as "mine" without
ever claiming one - this bug reintroduced, with no symptom at the call site.
- TransformFeedbackLifetimeIdTest, in its own translation unit, pins the
frontend halves: an object created on a recycled name must not report the dead
object's id, the default object has an identity before anything binds it, and
a PAUSED span still reads as open while another object is bound and capturing
- which is the whole correctness argument for the eviction rule. The name
reuse is not simulated: the test asks the real generator and skips (loudly) if
it never recycled. Still untested: the >16-owners path itself, which needs a
backend scenario with seventeen capturing objects and there is none.
- Negative controls, each applied then reverted: making a non-bound object's
span read as closed reddens APausedSpanStaysOpenWhileAnotherObjectCaptures;
making a vanished identity read as open reddens the same case on its delete
assertion; dropping the constructor's seeding reddens
AnObjectAtARecycledNameCarriesAFreshLifetimeId.
- Tested: cmake --build build-linux -j 24 (clean, 166 targets); ctest -L unit
-j 12 -> 1386/1386 passed; ctest -L integration-gpu -> 866/866 passed
serially, and 866/866 on one of two -j 8 runs. The other -j 8 run failed
DirectGLES.PointSizeDemotionScenario.TheDemotionIsActuallyArmedWhenTheEnviron
mentPinsItOn, a member of the pre-existing parallel-ctest flake family: it
passes in isolation here, and the unmodified parent tree
(~/w7/p0-noop-wins-base) reproduces the same family under -j 8.
- RenderbufferObject was the last state object a backend twin registry keys on
that could only be identified by its heap address or its GL name - both of
which recycle. BufferObject, VertexArrayObject and ProgramObject all carry a
process-wide, never-reused id for exactly this; the renderbuffer's absence is
named in plan B §10.4-5 as one of the two latent problems P0 closes.
- Mirrors BufferObject.h:202-208 / BufferObject.cpp:19-24 verbatim in shape: a
private static AllocateLifetimeId() over a namespace-scope
std::atomic<Uint64> starting at 1 (so a zero-initialised memo slot can never
carry a live object's id), a const member initialised from it at construction,
and an inline const getter. The doc comment is the buffer one restated for the
renderbuffer's own recycling sources.
- Deliberately NO GetVersion(): plan B §11 P0 says the id only. A mutation
counter would be a second, independent invalidation surface to keep correct,
and nothing needs one yet - the renderbuffer's mutable content already reaches
the backends through AllocateStorage / SetInternalFormat / SetSamples.
- No caller yet, by design: the id exists so §4.7.3's D1 rekey (and the
DirectGLES renderbuffer twin registry at Managers.h:1858) has something to key
on. It is a pure addition - no existing field, signature or answer changes.
- ObjectLifetimeIdTest gains the two cases the other two object types already
have, so the renderbuffer is covered by the same allocator-reuse probe: an
object rebuilt at a freed address must not answer to the dead one's id, and
two live ones must differ.
- Tested: cmake --build build-linux -j 24 (clean); ctest -R ObjectLifetimeId ->
6/6 passed (4 pre-existing + 2 new).
- GLFunctionsTable had three entries that are frontend queries wearing a
backend interface (plan B v2 §2.1(a)): GetIntegeri_v, GetInteger64i_v and
GetProgramiv. Two of them have NO caller at all - `grep -o
'gBackendFunctionsTable\.GL\.[A-Za-z_0-9]*'` outside MG_Backend/ lists 69
distinct entries and neither GetInteger64i_v nor GetProgramiv is among them -
so both table slots, both backends' implementations and both registrations are
deleted here. This is plan B §11 P0's first "strictly no-op free win".
- Nothing was moved into MG_Impl, because MG_Impl already answers all of it.
glGetInteger64i_v is served by GL_Getter.cpp:1240-1314, which handles the
indexed buffer queries itself and derives every other pname from its own
GetIntegeri_v ("Handing the leftovers straight to the backend instead made
glGetInteger64i_v disagree with glGetIntegeri_v on the very same pname").
glGetProgramiv is served by GL_Program.cpp, whose GL_COMPUTE_WORK_GROUP_SIZE
arm (:928-946) reads ProgramObject::GetComputeLocalSize - a link artifact of
the program the APPLICATION wrote, which is the only program in the
application's namespace. §4.7.1 class B.
- GetIntegeri_v stays, but only for what a backend genuinely owns. Its pure
frontend arms were unreachable: GL_Getter::GetIntegeri_v answers
GL_SHADER_STORAGE_BUFFER_{BINDING,START,SIZE} through
TryDecodeIndexedBufferQuery (:991-1029) and the six GL_IMAGE_BINDING_* pnames
at :1115-1153, and returns before touching the table. That left 9 dead cases
in DirectGLES.cpp and 9 in DirectVulkan.cpp - the plan's "15" undercounts the
two files separately. What still arrives is GL_MAX_COMPUTE_WORK_GROUP_COUNT /
_SIZE (GL_Getter.cpp:1161-1177, and MG_Util/ShaderTranspiler/CompileEnv.cpp
:134-138 asks the table directly), so DirectVulkan keeps exactly those two and
DirectGLES becomes a plain driver passthrough.
- The dead arms were also WRONG, which is why deleting rather than reconciling
them is the strict no-op: they clamped a bound range's size to the buffer's
current storage, while the frontend reports the size glBindBufferRange was
asked for verbatim (GL 4.6 core tables 23.4/23.5 - the clamp answered 0 for
KHR-GL43.shader_storage_buffer_object.basic-binding's shape). Had a later
refactor made the table the answer, the regression would have been silent.
- ProgramResourceCache::computeWorkGroupSize and the spirv-reflect entry-point
loop that filled it go with DirectVulkan's GetProgramiv; nothing else read it.
- Three cases added to AdvertisedLimitsScenario pin what the frontend answers,
on both lanes: the indexed SSBO binding/start/size on the 32- and 64-bit
widths INCLUDING a shrink of the store underneath the binding (the arm that
actually separates verbatim from clamped), the six image-unit pnames on both
widths, and the compute local size plus the INVALID_OPERATION a program with
no compute stage must give.
- Both new gates were shown to go red for their reason: making
GL_COMPUTE_WORK_GROUP_SIZE answer a defaulted (1,1,1) fails
ComputeLocalSizeComesFromTheLinkedProgram on both lanes, and re-introducing
the deleted store clamp in GL_Getter fails
IndexedBufferBindingsAreReportedVerbatimOnBothWidths on both lanes.
- Tested: cmake --build build-linux -j 24 (clean); ctest -L unit -j 12 ->
1382/1382 passed; ctest -R AdvertisedLimits -> 18/18 passed (6 pre-existing +
3 new, x DirectGLES and DirectVulkan).
- A window with no Present divided by a faked 1 and printed the window TOTALS under
"bytes/f[...]": the *MultiDraw* slice (47 draws, no present) reported 1,404,550 bytes as a
PER-FRAME figure, a 47x overstatement of exactly the SEG_STAGE sizing input plan B section
8.2 / section 11 P0 asks this package to produce. FormatWindowLine now relabels the bracket
to "bytes[...]" and prints draws/f=n/a when the window holds no frame; acc/draw=n/a follows
the same rule, because "0.00" beside a non-zero acc= is the same lie. Pinned by
PipeStatsTest.SummaryLineSurvivesZeroFrames and the reworked SummaryLineSurvivesZeroDraws.
- Every per-frame and per-draw field now goes through one FormatFixed2 helper. draws/f read 1
for 26 draws over 14 frames (1.86) and buf read 97 for 1360 bytes (97.14): a systematic
downward truncation of up to a whole unit on the figures the package exists to produce.
Pinned by PipeStatsTest.PerFrameFieldsKeepTwoDecimals.
- FormatSummaryLine rewrote the window bases as a side effect of formatting, so any second
reader silently zeroed the next window. Split into a pure FormatWindowLine() and an explicit
AdvanceSummaryWindow(); EmitSummaryLine calls both. Pinned by
PipeStatsTest.FormattingTwiceDoesNotConsumeTheWindow.
- Init() called ResetForTesting(), against the header's own "not used by any shipping path".
Both now forward to an internal ResetCounters().
- TracyPlot published only the MISS half of each gate under the gate's unqualified name, so
the headline output channel of section 11 P0 carried no denominator. Two series per gate now
("...-hit" / "...-miss") from static literal arrays. The payload histogram stays unplotted
and says why: it is a run-total distribution over draws (section 4.5.7), not a per-frame
scalar, and it reaches the operator through the JSON dump.
- GetOrCreatePipeline's 15-call tally sat ABOVE the list-topology primitive-restart refusal,
so a declined draw added ten reads it never made - an OVER-count, which breaks the lower
bound contract every other tally keeps. Moved to immediately before the payload build, and
the enumeration reconciled with the constant: the excluded read is the sample-shading
capability, short-circuited by m_sampleRateShadingFeatureEnabled.
- Six real staging paths were uncounted while the inventory claimed coverage. The inventory
claim "DirectVulkan's own buffer staging ... has no second copy to count" was simply false.
Now wired: MultiDraw.cpp's UploadScratch/UploadScratchRing (indirect commands, the compute
tier's draw-info array, the rebased index stream - the class is passed in, so a new tier
cannot forget it); Managers.cpp's pool-recycle reseed and the VBO-backed Float64 narrowing;
VkBufferManager's eight host->device copies of buffer contents plus UploadTransient, the
single chokepoint for Magma's per-draw vertex/index/indirect staging; VkTextureManager's
packed staging slice, with the same box/rect SHAPE split Espryt already reported.
- New byte class stage-indirect-cmd, for draw PARAMETER bytes a backend synthesises and
stages. Kept out of stage-index-client because these are the population that becomes MGPipe
command-record payload (section 4.5.7), not resource bytes. A name addition, not a rename:
no recorded baseline is invalidated.
- stage-ubo-named moved past the zero-copy direct-bind decision in ResolveUniformBufferPayload
(a direct bind repacks nothing, so counting it there reported a copy that never happened),
and Magma's default-uniform-block image now feeds stage-ubo-global the way Espryt's does,
counted after the per-frame slice memo.
- The site inventory in PipeStats.cpp is rewritten to name every unwired path by file and
function. An inventory that overstates coverage is worse than a missing counter, because
the zero is then read as an answer.
- Evidence, lavapipe/llvmpipe, MOBILEGL_PIPE_STATS=1: the MultiDraw slice now prints
"window=0 draws/f=n/a bytes[buf=1404550 ...]"; the indirect tiers
(MOBILEGL_ESPRYT_MULTIDRAW_MODE=indirect|multiindirect) move icmd 0 -> 660; Magma's GuiBatch
line moves from buf=0 tex=0 ubog=0 to buf=685.71 tex=41.14 ubog=157.71 with tex[emit=9
box=9 rect=0 jobs=9]. Off-path A/B against the base tree with the env unset, 9 runs each of
a 40-scenario draw slice, sorted totals in ms: Espryt base 389..794 (median 399) vs branch
384..403 (median 394); Magma base 406..472 (median 410) vs branch 408..761 (median 414) -
the always-compiled guard is below this harness's noise on both backends.
- 1410 unit tests green (15 PipeStatsTest). integration-gpu 860/860, 860/860, 859/860; the one
failure is DirectVulkan.PointSizeDemotion...TheDemotionIsActuallyArmedWhenTheEnvironmentPins-
ItOn, a member of the load-dependent *IsActuallyArmed* flake family already present in the
untouched base tree, and it passes 8/8 standalone here. stdio gate and gen_pipe check green.
- The sites of plan B section 2.3.1, verified against dev@81b17c0b (the plan's own line
numbers for DirectGLES drift by 4-9 lines; the DirectVulkan ones are exact):
SyncRenderState is DirectGLES.cpp:1994 with the version read at :1998 and the
early-out at :2007-2010 (plan says 2003 / 2007 / 2016-2018); SyncNeccessaryTextures
at :1511 (plan :1520); CurrentUnitBindingsEpoch at :1412-1435 (plan :1418-1436);
PrepareForDraw at :2907-2968 (plan :2916-2976); the global-UBO upload at :3355-3397
(plan :3369-3392); TrySetupDrawFastPath :5994, GetOrCreatePipeline :4948-4993,
ApplyDynamicDrawStateTail :5871-5893 and UniformManager ResolveUniformBufferPayload
:2022/:2052 all as cited.
- Accessor counting is STATIC TALLIES at ten hot entry points, not a wrapper around the
293 pGLContext-> sites: each instrumented function adds the number of accessor calls
its own body made on the path taken. Reads inside callees, and every conditional read
(the sRGB capability in SyncRenderState, the XFB probe and the version-gated parameter
fetch in TrySetupDrawFastPath, the cull-mode/logic-op/tessellation reads in the
pipeline payload builder) are excluded, so the number is a consistent LOWER bound. The
full inventory of what is and is not counted is the header comment of PipeStats.cpp.
- The Magma fast-path gate is counted from SetupDraw, not from inside
TrySetupDrawFastPath: that function has 27 decline returns and one success return, and
counting at the caller is the only shape that cannot miss one.
- The texture upload counts the SHAPE (union box vs N-rect list) separately from the
bytes, because SSIM is blind to the shape and the +6 ms/frame Mali regression of
section 7.3 was a shape regression, not a byte one.
- Frame boundary: DirectGLES::Present after the ring upkeep, and DirectVulkan's backend
Present rather than VulkanRenderer::Present - the latter has an early return for the
no-usable-swapchain case, and a suspended frame is still a frame the counters close.
- Measured on lavapipe/llvmpipe with MOBILEGL_PIPE_STATS=1, GuiBatchScenario, 14 frames
and 26 draws: Espryt 20.65 accessor calls per draw (gates ers 22/18, etl 71/9, eub
71/9), Magma 15.54 (mfp 12/14, mpm 0/14, mdt 12/14). Both land inside the 10-25 band
section 2.3.1 predicted and far below the 124/169 static counts, which is the
correction that section was written to force.
- Plan B section 11 P0 asks for TracyPlot per-frame counters on both sides of the
boundary, and section 2.3.1 adds the deliverable v1 did not have: DYNAMIC call
counters. The static call-site counts everyone quotes (Espryt 124 / Magma 169) are
not the per-draw cost, because every one of those paths is memo-gated; without a
dynamic counter P2's verdict stays a guess. The tree had no per-frame byte or call
measurement at all - MG_Util/Metrics is format arithmetic, and Tracy has zones but
no plots.
- Cost when off: g_pipeStatsEnabled is a plain global Bool latched once in
Initialize() right after MG_ConfigLoader::Init(), and every counting site is
`if (PipeStats::Enabled()) ...` - one load of a hot global and one never-taken
branch. The counters are relaxed atomics because buffer and texture staging are
reachable from more than one thread; the off path never touches them.
- Eight byte classes (stage-buffer, stage-texture, stage-ubo-global, stage-ubo-named,
stage-vertex-client, stage-index-client, persistent-map-push and the
residual-value-block placeholder of section 6.3), six call classes and the six memo
gates of section 2.3.1, each as a hit/miss pair. Names are minted now, including the
two that stay 0 in P0, so no recorded baseline is invalidated by a later rename -
which is why the name set is pinned by a test.
- Reporting: TracyPlot per counter per frame when TRACY_ENABLE; with
MOBILEGL_PIPE_STATS=1 one MGLOG_I summary line every 120 frames and at teardown, plus
a JSON dump to MOBILEGL_PIPE_STATS_FILE when that is set. MGLOG_I against the usual
"MGLOG_D for non-critical" rule on purpose: the line has to survive an INFO build -
the only build a device runs - it is at most one line per 120 frames, and it exists
only when the operator asked for it.
- Summary lines report disjoint WINDOWS, not run totals: a run total over a workload
that changes shape (load, then steady state) averages away the very number section
2.3.1 wants an absolute value for.
- MOBILEGL_PIPE_STATS_FILE joins the six switches parsed in e48a3582; like them it
needs no allow-list entry because InitializeAcceptedEnvVariables accepts every
MOBILEGL_-prefixed variable by construction.
- Three P0 gates from plan B section 11, in one job that needs no build: a broken build
must not be able to hide a drifted interface.
- pipe-gen-check regenerates G1-G7 and runs git diff --exit-code over
MobileGL/MG_Pipe/generated. Since all seven generators read the same .def files, this is
what makes drift between them impossible rather than merely unlikely.
- The stdio gate refuses fprintf(stderr and printf( under MG_Backend and MG_State. Nothing
there matches today, so it lands with NO whitelist - verified with a negative control
that fprintf(stderr and std::printf both trip it while snprintf does not. Per-draw
instrumentation has been committed by accident before, once inside a mutex critical
section, and MGLOG_D is the channel these trees are allowed to use because it compiles
out in INFO builds.
- scripts/gen_pipe_dirty_surface.py reports the frontend mutation surface corollary 4
needs covered: 926 mutator calls under MG_Impl/GLImpl over 73 distinct mutators, of
which only 92 sit in a function that also reaches the backend. The other 834 are
published by the NEXT verb, which is precisely the population that needs an aggregate
generation. Informational in P0; it becomes a gate in P1 when there is a mapping file to
diff against.
- scripts/check_doc_citations.py resolves every `path:line` citation against a git
revision. It reproduces the failure that motivated it - the plan's first draft cited
SamplerObject.h:468-492 in a 160-line file - and reports 84 unresolved citations out of
1028 in docs/Disaggregated today, which is why CI runs it warning-only until those
documents settle. --strict exits 1, verified in both directions.
- Appendix B of plan B. All six default to today's behaviour: PipePush 0 is "pull
everything", verify and stats off, legacy memos ON so the first handle waves keep a real
old-versus-new arm (B-R16), texel retain 0 because MipmapStorage already holds a complete
CPU shadow so that cache buys latency and never correctness (section 7.5c), index mirror
64 MiB.
- No allow-list edit is needed and the header says why: InitializeAcceptedEnvVariables
accepts every MOBILEGL_ / LIBGL_ prefixed variable found in the environment, so a name
with that prefix is visible to these queries by construction - the failure mode of a
hand-maintained accepted list does not exist here.
- PipeLegacyMemos defaults ON, so it is read as a tri-state (QueryEnvQuirkOverride !=
ForceOff) rather than as a plain truthy flag: unset must keep the memos and only an
explicitly falsy value may drop them. Reading it with QueryEnvFlag would have inverted
the default silently.
- QueryEnvUint64 is added alongside QueryEnvUint32 for the subsystem bitmask, accepting a
0x prefix - a bitmask written in decimal is unreadable - and warning and falling back to
the default on anything unparseable, exactly like its 32-bit sibling.
- Thirteen cases that need no GL context and no driver, so the fact that PipeCalls.def and
the seven generated files agree is checked on every unit run rather than at review time.
- The catalogue count is one fact stated three times - the macro expansion,
MGP_CALL_LIST_DOCUMENTED_COUNT and the two generated tables - and the per-class counts
documented in the .def header are asserted individually, which is what caught kCtxState
being 17 rather than 18 (set_texture_params carries kCtxObject, per the plan's own
example in section 4.1).
- An uninstalled pipe must be all-null: that is what "this subsystem has not been migrated,
keep pulling" means (section 4.1), so it is asserted rather than assumed.
- The comparator test pins the two properties the verify harness depends on: the FIRST
differing field is named, and padding is not a field - two payloads that differ only in
padding compare equal, while a nested array element does not.
- The poison test pins the per-verb behaviour a bitmap cannot express: a field filled for
verb N is stale at verb N+1.
- Plan B section 4 makes the frontend/backend boundary explicit and gives the backend its
own state machine. This is the P0 deliverable of section 11: the whole catalogue exists
from day one, placeholders included, because the wire opcode is a call's position in
PipeCalls.def and record numbering must never churn.
- MG_Pipe/PipeCalls.def is the single source of truth: 68 unique calls as
X(Name, Payload, Class, Flags). Its header reconciles that number with the plan's
headline counts (section 4.4, appendix A), which double count - "CSO 15" names
bind_sampler_states and set_sampler_views that the "set_* 17" list also names, "screen
14" tabulates the query family that section 4.3 assigns to the context, and the
"transfer 12" row enumerates 11 calls. Each reconciliation is written down next to the
count rather than resolved silently.
- MGPipeHandles.h: the 8-byte {slot, gen} pair, dense per-kind slots, the reserved null
and default-framebuffer handles, and the ShaderCso composite band (sections 4.2, 5.6.3).
The two generations are documented as strictly separate, with the interface rule that no
call may require the client to know MGGen.
- MGPipeTypes.h: every payload of section 4.5 as a flat POD with explicit padding, a
trivial-copyability assertion and an exact sizeof assertion, because the wire records are
memcpy'd and a field silently changing width is a protocol break no test would see.
MGPCaps embeds DynamicBackendParameters by inclusion so a caps field added there needs no
second edit here; its assertion is stated as a composition because that struct still
carries SizeT. ResidualValueBlock is pinned at MGL_RESIDUAL_BLOCK_SIZE 1248, the ratchet
that only ever goes down and reaches static_assert(... == 0) in P13 (section 6.3).
- MGPipeHostSpan.h keeps the one shape that changes with the transport isolated behind one
predictable branch, with the kFromServerIndexMirror sentinel D-B7 needs.
- MGPipeCallbacks.h names the reverse channel as ten callbacks plus the forward terminator
in the context table, replacing 95 poke sites across 17 methods (section 7.1).
- scripts/gen_pipe.py runs G1-G7 off those .def files. G1 asserts each table is EXACTLY its
call count of function pointers; G3 pads every wire record to the stream's 8-byte
granularity and checks size >= sizeof && size <= remaining && size % 8 == 0 before
dispatch, fatally; G4 compares field by field (padding excluded, floats by bits) because
a comparator with false positives is one nobody reads - DirectGLES.cpp says the same
thing about its own memcmp of RenderStateParameters; G5 turns the accessor list into
per-verb poison generations rather than a written-once bitmap, which is the only version
that can see a field left over from the previous draw (section 6.2.2); G6 joins the 477
read points of the vendored backend_read_inventory.md against Coverage.def and reports
0 UNMAPPED (299 to a call, 167 signatures that become handle parameters, 6 reverse
channel, 5 client-resolved); G7 pins the pipeline subset BY MEMBER NAME from what
VulkanRenderer::ComputePipelineStateHash hashes today, computing no offsets in python.
- The generated files are committed so the build never depends on python; CI regenerates
and diffs them.
- docs/Disaggregated/PLAN.md is now the one plan: the MGPipe design with the transport, control-plane, present, threading, EGL/process, monolith/build chapters inlined as real chapters (7-13) instead of references, sections renumbered 0-17 + appendices, every internal citation updated
- the replica-GLContext plan and its review record are removed at the user's request; REVIEW.md is the MGPipe design-competition and adversarial-review record only, with the comparison verdicts dropped and the remaining finding text reworded to the new section numbers
- day-43 GO/NO-GO now names its two outcomes (continue / shrink to headless tooling or re-evaluate) without any rollback path
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