mirror of
https://github.com/MobileGL-Dev/MobileGL
synced 2026-11-07 01:53:24 +09:00
BZLZHH
33e02f4bcf
- MGPipeSubDataWantsItsReply is the ONE place that decides whether a resource_subdata record waits
for its answer (WireTables.cpp:370 and PipeRoute.h:328 both read it, and the comment beside it
says that a second spelling is how the client comes to wait for an answer the emitter told the
server not to bother with). The buffer half has answered "no" since P5e; the texture half now
does too, ON THE WIRE ARM ONLY.
- THE ANSWER IS DERIVABLE THERE, which is the argument - not that nobody reads it:
* The emission is already gated on the answer's content. A texture record is produced only where
FamilyIsLive(kMGPipeSubsystemTextureResources, ...) holds, and under split that gate IS
CapsMirrorInstance().ServerConsumes(bit 10) (PipeFill.cpp:1719-1740) - the same published fact
the applier's own acceptance belt reads (PipeApply.cpp:1408-1419, NoP4aConsumer). So the one
refusal this acceptance exists to carry, "no consumer" (ID-39 / D-D5 / ID-18 M3, which is why
the texture half ever asked), cannot be the answer to a record this client emitted.
* What remains is a bug class, and it is loud already: a record that names no texture, declares
no texels or carries no bytes is an MGP_TRIP_WIRE_REPORT (PipeApply.cpp:1201-1218, :2245-2252),
and a handle the applier does not hold is counted and named (ResolveResourceIn, :721-728) with
the client's own tracker preventing it from arising (PipeFill.cpp:1045-1051).
* Every answer the client can still get for free, it still gets: the emitter reads this route's
Bool exactly as before, so a record the CLIENT cancelled (the device-lost latch, an exhausted
stage) still answers "not accepted" and the level stays dirty and is retried - D-D5's safe
direction, unchanged.
- THE WAIT MOVES TO THE STAGE. A run that does not fit SEG_STAGE reclaims retired bytes and parks
on the stage doorbell (PipeWireCodec.cpp StageAllocate / ReclaimStagedBytes) - the one wait a
run-ahead client owes, and it is proportional to the WINDOW rather than to the call count. On
Minecraft 26.2's atlas frame that is the handoff's 55,428 reply waits at ~4.4 ms each: 96 MiB of
uploads through a 32 MiB window.
- THE GATE IS THE NUMBER ITSELF. LinkMetricsReplyWaits is added so a case can read back the same
`wait_replies` the per-frame P65LinkMetrics line prints - LinkMetrics.cpp:76-80 counts exactly
the records that own a reply slot. TextureUploadsStopOwningAReplyOnTheWireArm asserts that a pure
glTexSubImage2D crosses the wire and moves it by ZERO, while a resource_create row - kWaitReply,
and it always was - still moves it, so the zero cannot be "nothing was counted". Red-once run:
with the arm test removed the child exits 142.
- Monolith and every non-wire arm are untouched, and that is pinned twice: the existing
RemoteRunAhead.OnlyTheTextureHalfOfResourceSubDataWantsItsReply still reads true with no arm
installed, and the new test sits inside MOBILEGL_BUILD_DISAGGREGATED with the original expression
as its fall-through, so a pull build preprocesses to the line it had (G1).
- Verification debt, stated rather than implied: the host gate is the COUNT, not a wall clock.
In-process control sessions run lockstep (the caps peer publishes no kCapRunAheadApply), so the
verb barrier still waits there; the end-to-end wall-clock win is the device measurement the
handoff describes and it has not been taken yet.