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Normalize TPUSH/TPOP usage and add interim onboard lane-offset bridge
Converge MIX GM FIFO tile-pipe kernels to pto-isa default semantics: - Remove redundant manual prod.record() and setRecordStatus(false) / setAllocateStatus(false) / setFreeStatus(false) from spmd_paged_attention - Rely on built-in TPUSH/TPOP/TFREE record and back-pressure; keep existing set_flag/wait_flag pipeline sync unchanged - Fix bgemm AIV GM accumulator row addressing via get_sub_block_id(args) instead of stale CCE get_subblockid() Work around a known pinned pto-isa bug on 1C2V MIX where get_subblockid() returns 0 for both AIV lanes, breaking TILE_UP_DOWN lane offsets inside the library. Until pto-isa/dispatch fixes sub-block identity, inject GlobalContext.sub_block_id through intrinsic.h tpipe_lane_byte_offset() + setEntryOffset as an interim bridge. Docs and validation: - Add docs/tpush-tpop.md; update aicore-kernel-programming.md - Drop spmd_paged_attention pytest skip - Onboard SmallCase1 / Case2 / Case1 golden checks pass Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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docs/aicore-kernel-programming.md

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@@ -184,18 +184,25 @@ down from `kernel_entry` into `UnpadAttentionDecoderAic::SetArgs` and
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The porting checklist above assumes you own every `get_subblockid()` call
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site. You do **not** when the kernel drives the pto-isa tile-pipe library
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(`TPUSH` / `TPOP` / `TFREE` with `TileSplitAxis::TILE_UP_DOWN` or
187-
`TILE_LEFT_RIGHT`): those templates compute their per-AIV FIFO offset from the
187+
`TILE_LEFT_RIGHT`): those templates compute per-AIV FIFO offset from the
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**no-arg** `get_subblockid()` internally
189-
(`TPush.hpp::pushVec2GMFiFo` / `popVecTileFromGMFiFo`
190-
`subAIVOffset = get_subblockid() * rows * cols * sizeof(T)`), and you cannot
189+
(`TPush.hpp::pushVec2GMFiFo` / `popVecTileFromGMFiFo`), and you cannot
191190
thread `args` into a third-party library template.
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Under simpler's MIX dispatch that library call returns 0 for both lanes, so its
194-
auto-split contributes nothing and **both AIV lanes read/write the same FIFO
195-
half**. The other half is never produced; attention then reads uninitialised GM
196-
and the output is wrong/partial (observed as `NaN` in the qwen3 case here).
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**Recommended usage** (see [`docs/tpush-tpop.md`](tpush-tpop.md)):
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198-
**Do not** bridge it with a file-scope cache:
194+
- Call `TPUSH` / `TPOP` / `TFREE` directly — record, back-pressure, and
195+
`TILE_UP_DOWN` lane offset are already implemented inside those templates.
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- Do **not** add manual `pipe.prod.record()` or batch `setRecordStatus(false)` /
197+
`setAllocateStatus(false)` / `setFreeStatus(false)` unless a reviewed pipeline
198+
analysis requires it.
199+
- Do **not** `setEntryOffset(get_sub_block_id(args) * …)` for lane split when
200+
`get_subblockid()` is correct — the library already adds
201+
`get_subblockid() * tile_bytes_per_lane`.
202+
- For **non-tile-pipe** GM addressing (output rows, head partitioning), keep
203+
using `get_sub_block_id(args)` from this header.
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**Do not** bridge `get_subblockid()` with a file-scope cache:
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```cpp
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// WRONG — the .o will not load. See §4.
@@ -205,25 +212,11 @@ and the output is wrong/partial (observed as `NaN` in the qwen3 case here).
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```
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A `[[block_local]]` (or any non-const) static is read via a `.text` relocation
208-
that the AICore loader rejects (§4), and AICore forbids ordinary global/static
209-
data, so there is no relocation-free global to redirect into either.
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The working pattern (as in `spmd_paged_attention`) leaves the library's
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`get_subblockid()` at its native 0 and adds the per-lane offset **explicitly**
213-
on the tile-pipe, computed from `get_sub_block_id(args)`:
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```cpp
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int32_t lane = get_sub_block_id(args); // 0 or 1, real lane
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// TILE_UP_DOWN splits an M×N tile by rows; AIV1 starts one sub-tile in.
218-
pipe.cons.setEntryOffset(lane * Rows * Cols * sizeof(ConsT)); // C2V pop side
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pipe.prod.setEntryOffset(lane * Rows * Cols * sizeof(ProdT)); // V2C push side
220-
```
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The library adds `get_subblockid() * bytes` (= 0) **plus** your `entryOffset`,
223-
so the explicit offset now carries the entire lane split. Set it once after the
224-
pipe is constructed; `entryOffset` persists across `TPUSH` / `TPOP`. See
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`examples/a2a3/tensormap_and_ringbuffer/qwen3_14b_decode/kernels/aiv/fa_fused_aiv.cpp`
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for a worked example.
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that the AICore loader rejects (§4). If onboard `get_subblockid()` does not
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match `get_sub_block_id(args)`, prefer fixing platform/launch identity; until
217+
then add the lane split explicitly with `setEntryOffset` computed inline from
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`get_sub_block_id(args)` (see the `run_aiv` `setEntryOffset` call sites in
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[`spmd_paged_attention/kernels/mix/paged_attention_parallel.cpp`](../tests/st/a2a3/tensormap_and_ringbuffer/spmd_paged_attention/kernels/mix/paged_attention_parallel.cpp)).
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---
229222

@@ -258,9 +251,9 @@ readelf -SW kernel.o | grep -E '\.text' # want only ".text"; ".text._Z*" or ".r
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readelf -r kernel.o # want: no relocation entries
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```
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This is exactly why §3's sub-block-id fix uses an explicit `setEntryOffset`
262-
argument rather than a cached `[[block_local]]` static: the static would
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reintroduce a `.rela.text` the loader rejects.
254+
This is exactly why §3 rejects a cached `[[block_local]]` static to redirect
255+
`get_subblockid()`: the static would reintroduce a `.rela.text` the loader
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rejects.
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---
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docs/tpush-tpop.md

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# TPUSH/TPOP Usage Guidelines (Advisory)
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Recommended patterns for MIX kernels that use GM FIFO tile-pipe (`TPipe` +
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`TPUSH` / `TPOP` / `TFREE`, commonly with `TileSplitAxis::TILE_UP_DOWN`).
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New kernels and refactors should follow these by default; special pipelines
6+
may deviate after review. This is not a hard lint.
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Implementation reference: `pto-isa/include/pto/npu/*/TPush.hpp`, `TPop.hpp`.
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## Why (overview)
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pto-isa's `TPUSH` / `TPOP` / `TFREE` already embed record handling,
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allocate/back-pressure, and lane offset computation under
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`TILE_UP_DOWN`. Re-implementing the same logic in kernel code is usually
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redundant and can diverge from the built-in path. Prefer calling TPUSH/TPOP
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directly and leave the cross-core FIFO protocol to the library.
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## 1. Prefer TPUSH/TPOP directly — do not manual-record
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**Why**: `TPUSH_IMPL` / `TPOP_IMPL` call `prod.record()` / consumer wait
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after push/pop when `getRecordStatus()` is true (the default). Cross-core
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handshake is already inside TPUSH/TPOP.
23+
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- Default `TPUSH_IMPL` flow: `allocate``push` (TSTORE to GM FIFO) →
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`tileIndex++``record()`.
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- **Prefer**: call `TPUSH(...)` / `TPOP(...)` only; do not also call
27+
`pipe.prod.record()`.
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- **Prefer**: do not call `setRecordStatus(false)` to disable built-in
29+
record; combining with manual record is usually redundant and easy to
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miss a signal.
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- Pipeline `set_flag` / `wait_flag` and TPUSH record are **independent**:
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the former synchronizes MTE/M/V pipeline stages; the latter handles
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cross-core FIFO handshake. Keep each where needed — this rule does not
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constrain flag usage.
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- If C2V AccTile still has record timing issues on a specific pto-isa
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version, prefer upgrading pto-isa or the platform bridge over keeping
37+
manual record long-term.
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## 2. Prefer default back-pressure — do not bulk-disable status flags
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**Why**: TPUSH already calls `prod.allocate()` when needed via
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`getAllocateStatus()` (default true). The consumer path with `TFREE` uses
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consumer free sync. That back-pressure lives in TPUSH/TPOP/TFREE; turning
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it off requires the kernel to guarantee slots never overflow.
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- Producer default `isAllocate=true`: when the FIFO is full, `allocate()`
47+
waits for consumer `TFREE`.
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- Consumer default enables free sync: after consume, the slot is released
49+
to the producer.
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- **Prefer**: do not batch `setAllocateStatus(false)` / `setFreeStatus(false)`
51+
at kernel entry unless pipeline analysis proves `FIFO_DEPTH` and scheduling
52+
order already guarantee safe slot reuse — and document the rationale in a
53+
comment.
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55+
## 3. Rely on TILE_UP_DOWN auto lane offset — do not manual setEntryOffset
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**Why**: under `TileSplitAxis::TILE_UP_DOWN`, `TPUSH` / `TPOP` / `TFREE`
58+
compute `subAIVOffset` via `get_subblockid()` inside
59+
`pushVec2GMFiFo` / `popVecTileFromGMFiFo` and related paths. Calling
60+
`setEntryOffset(get_sub_block_id(args) * …)` on top duplicates or stacks
61+
with the library offset.
62+
63+
- Library path: `subAIVOffset = get_subblockid() * tile_bytes_per_lane`
64+
(expanded by split axis and tile shape).
65+
- **Prefer**: do not use
66+
`pipe.cons/prod.setEntryOffset(get_sub_block_id(args) * …)` for lane
67+
splitting; ensure the platform provides a correct `get_subblockid()`.
68+
- **Known issue (current pinned pto-isa)**: on 1C2V (1 Cube + 2 Vector)
69+
MIX, CCE `get_subblockid()` returns 0 for both AIVs, so library
70+
`subAIVOffset` cannot distinguish lanes — a pto-isa / launch identity
71+
bug, not kernel misuse.
72+
- **Onboard bridge (interim)**: when that applies (or simpler dispatch has
73+
not yet programmed sub-block registers), add the lane split explicitly on
74+
the tile-pipe with `setEntryOffset(get_sub_block_id(args) * sub_rows * cols *
75+
elem_bytes)` (`GlobalContext.sub_block_id`) — see the `run_aiv`
76+
`setEntryOffset` call sites in
77+
[`paged_attention_parallel.cpp`](../tests/st/a2a3/tensormap_and_ringbuffer/spmd_paged_attention/kernels/mix/paged_attention_parallel.cpp).
78+
Remove once pto-isa / dispatch fixes `get_subblockid()`.
79+
80+
## Reference examples
81+
82+
- [`tests/st/a2a3/tensormap_and_ringbuffer/spmd_paged_attention/kernels/mix/paged_attention_parallel.cpp`](../tests/st/a2a3/tensormap_and_ringbuffer/spmd_paged_attention/kernels/mix/paged_attention_parallel.cpp)
83+
- [`examples/a5/tensormap_and_ringbuffer/bgemm/kernels/mix/kernel_bgemm.cpp`](../examples/a5/tensormap_and_ringbuffer/bgemm/kernels/mix/kernel_bgemm.cpp)

examples/a2a3/tensormap_and_ringbuffer/qwen3_14b_decode/README.md

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@@ -44,9 +44,11 @@ per-layer KV pools.
4444
The kernels are used essentially as generated, with **one hand-edit** to
4545
`fa_fused_aiv`: the codegen emitted the AIV sub-block id as a `[[block_local]]
4646
static` (`pypto_runtime_subblock_id`) whose **non-branch** `.text` relocation
47-
simpler's strict `.text`-only loader rejects. The fix swaps it for the pto-isa
48-
explicit-offset pattern (`setEntryOffset(get_sub_block_id(args) * …)`) — no
49-
per-core static, no relocation. See Status below.
47+
simpler's strict `.text`-only loader rejects. The fix swaps it for
48+
`setEntryOffset(get_sub_block_id(args) * …)` (legacy workaround). New MIX
49+
kernels should prefer direct `TPUSH`/`TPOP` per
50+
[docs/tpush-tpop.md](../../../docs/tpush-tpop.md). See
51+
Status below.
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5153
To regenerate: in pypto-lib, set `_CHUNK_NLAYERS=2`, `PTO2_MANUAL_MAX_SEQ=5500`,
5254
build the ×2-stacked inputs, and `decode_fwd_layers.compile_for_test(...)`; then
@@ -99,6 +101,6 @@ static and macro, and apply the per-lane split explicitly on the tile-pipe in
99101
nothing) and the explicit offset carries the lane separation. No per-core static,
100102
no relocation — loads under the strict loader and computes correctly.
101103

102-
The cleaner long-term fix is upstream codegen: have pto-isa emit the explicit
103-
`sub_block_id` offset directly, or have the runtime program the FFTS sub-block
104-
register so native `get_subblockid()` returns 0/1.
104+
The cleaner long-term fix is direct `TPUSH`/`TPOP` with platform-correct
105+
`get_subblockid()` (see [docs/tpush-tpop.md](../../../docs/tpush-tpop.md)
106+
and [`spmd_paged_attention`](../../../../tests/st/a2a3/tensormap_and_ringbuffer/spmd_paged_attention/kernels/mix/paged_attention_parallel.cpp)).

examples/a5/tensormap_and_ringbuffer/bgemm/kernels/mix/kernel_bgemm.cpp

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@@ -50,9 +50,11 @@ using pto::TPipe;
5050
#endif
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5252
#ifndef __aicore__
53-
#define __aicore__
53+
#define __aicore__ [aicore]
5454
#endif
5555

56+
#include "intrinsic.h"
57+
5658
#ifdef __DAV_CUBE__
5759
constexpr bool DAV_CUBE = true;
5860
#else
@@ -159,7 +161,8 @@ extern "C" __aicore__ void kernel_entry(__gm__ int64_t *args) {
159161
// Vector side: TPOP result from cube → TLOAD C from GM → TADD → TSTORE
160162
// =========================================================================
161163
if constexpr (DAV_VEC) {
162-
uint32_t subBlockIdx = get_subblockid();
164+
int32_t sub_id = get_sub_block_id(args);
165+
uint32_t subBlockIdx = (sub_id >= 0) ? static_cast<uint32_t>(sub_id) : 0U;
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164167
__gm__ float *c_ptr = reinterpret_cast<__gm__ float *>(c_tensor->buffer.addr) + c_tensor->start_offset;
165168
// Each vector sub-core handles its half: sub-core 0 → rows [0, VEC_M),

tests/st/a2a3/tensormap_and_ringbuffer/spmd_paged_attention/kernels/mix/paged_attention_parallel.cpp

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@@ -198,12 +198,9 @@ static __aicore__ void aic_qk_step(
198198
set_flag(PIPE_M, PIPE_FIX, EVENT_ID0);
199199
wait_flag(PIPE_M, PIPE_FIX, EVENT_ID0);
200200

201-
// TPUSH sij (C2V): AccTile L0C -> GM. Ensure prior MTE3 is done,
202-
// then push, then wait for MTE3 DMA to complete before signaling consumer.
203201
TPUSH<SijPipeT, AccTile_QK, TileSplitAxis::TILE_UP_DOWN>(sij_pipe, cTile_QK);
204202
set_flag(PIPE_FIX, PIPE_S, EVENT_ID7);
205203
wait_flag(PIPE_FIX, PIPE_S, EVENT_ID7);
206-
sij_pipe.prod.record();
207204
}
208205

209206
// Helper: PV matmul for block i — TPOP pij, load value, move to L0, matmul, TPUSH oi
@@ -255,11 +252,9 @@ static __aicore__ void aic_pv_step(
255252
set_flag(PIPE_M, PIPE_FIX, EVENT_ID1);
256253
wait_flag(PIPE_M, PIPE_FIX, EVENT_ID1);
257254

258-
// TPUSH oi (C2V): AccTile L0C -> GM. Same manual record pattern as sij.
259255
TPUSH<OiPipeT, AccTile_PV, TileSplitAxis::TILE_UP_DOWN>(oi_pipe, cTile_PV);
260256
set_flag(PIPE_FIX, PIPE_S, EVENT_ID7);
261257
wait_flag(PIPE_FIX, PIPE_S, EVENT_ID7);
262-
oi_pipe.prod.record();
263258
}
264259

265260
template <typename Cfg, int K, int N>
@@ -642,30 +637,6 @@ static __aicore__ void run_aic(
642637
typename Cfg::PijPipeT pij_pipe(pij_fifo_base, 0U, Cfg::PIJ_L1_BASE);
643638
typename Cfg::OiPipeT oi_pipe(oi_fifo_base, Cfg::OI_UB_BASE, 0U);
644639

645-
// Disable auto-record on C2V pipes: AccTile TSTORE goes through FIX → MTE3,
646-
// but auto-record fires on PIPE_FIX which may complete before MTE3 DMA writes
647-
// to GM. Manual pipe_barrier(PIPE_MTE3) + record() in each step ensures the
648-
// cross-core signal fires only after the GM write is visible.
649-
sij_pipe.prod.setRecordStatus(false);
650-
oi_pipe.prod.setRecordStatus(false);
651-
652-
// Disable reverse-dependency sync (back-pressure). Forward dependency chain
653-
// (AIC: QK-first; AIV: SF-first; FIFO_DEPTH=2) guarantees producer is at
654-
// most SLOT_NUM=2 tiles ahead of consumer:
655-
// sij: AIC pushes sij[i+1] only after TPOP(pij[i-1]), which requires
656-
// AIV TPOP(sij[i-1]) — slot reuse safe.
657-
// oi : AIC pushes oi[i+1] only after TPOP(pij[i+1]), which requires
658-
// AIV's iter i+1 SF, by which time AIV iter i finished UP[i-1]
659-
// i.e. TPOP(oi[i-1]) — slot reuse safe.
660-
// pij: AIV pushes pij[i+1] only after TPOP(sij[i+1]), which fires after
661-
// AIC iter i+1 starts and AIC iter i has finished TPOP(pij[i-1])
662-
// — slot reuse safe.
663-
// If the QK-first/SF-first interleaving or FIFO_DEPTH changes, restore
664-
// these flags.
665-
sij_pipe.prod.setAllocateStatus(false);
666-
oi_pipe.prod.setAllocateStatus(false);
667-
pij_pipe.cons.setFreeStatus(false);
668-
669640
__gm__ Tensor *query_t = reinterpret_cast<__gm__ Tensor *>(args[0]);
670641
__gm__ Tensor *key_cache_t = reinterpret_cast<__gm__ Tensor *>(args[1]);
671642
__gm__ Tensor *value_cache_t = reinterpret_cast<__gm__ Tensor *>(args[2]);
@@ -718,22 +689,16 @@ static __aicore__ void run_aiv(
718689
int32_t sub_block_id = get_sub_block_id(args);
719690
int64_t row_offset = sub_block_id * Cfg::SUB_QT;
720691

721-
// Entry offsets depend on the actual tile width (block_size for sij/pij, HEAD_DIM for oi).
722-
// TILE_UP_DOWN splits Q_TILE rows into two SUB_QT halves; AIV1's data starts at
723-
// SUB_QT * tile_width * sizeof(element) within the contiguous TPUSH'd tile.
724-
int sij_sub_offset = sub_block_id * Cfg::SUB_QT * static_cast<int>(block_size) * static_cast<int>(sizeof(float));
725-
int pij_sub_offset =
726-
sub_block_id * Cfg::SUB_QT * static_cast<int>(block_size) * static_cast<int>(sizeof(bfloat16_t));
727-
int oi_sub_offset = sub_block_id * Cfg::SUB_QT * HEAD_DIM * static_cast<int>(sizeof(float));
728-
sij_pipe.cons.setEntryOffset(sij_sub_offset);
729-
pij_pipe.prod.setEntryOffset(pij_sub_offset);
730-
oi_pipe.cons.setEntryOffset(oi_sub_offset);
731-
732-
// Mirror reverse-dependency disable on the AIV side (see run_aic for
733-
// the full forward-chain argument).
734-
pij_pipe.prod.setAllocateStatus(false);
735-
sij_pipe.cons.setFreeStatus(false);
736-
oi_pipe.cons.setFreeStatus(false);
692+
// pto-isa TPUSH/TPOP add `get_subblockid() * sub_rows * cols * elem_bytes` internally, but the CCE
693+
// `get_subblockid()` register is 0 for both lanes under simpler onboard MIX dispatch; add the lane split
694+
// explicitly from GlobalContext.sub_block_id (block_size wide for sij/pij, HEAD_DIM for oi).
695+
sij_pipe.cons.setEntryOffset(
696+
sub_block_id * Cfg::SUB_QT * static_cast<int>(block_size) * static_cast<int>(sizeof(float))
697+
);
698+
pij_pipe.prod.setEntryOffset(
699+
sub_block_id * Cfg::SUB_QT * static_cast<int>(block_size) * static_cast<int>(sizeof(bfloat16_t))
700+
);
701+
oi_pipe.cons.setEntryOffset(sub_block_id * Cfg::SUB_QT * HEAD_DIM * static_cast<int>(sizeof(float)));
737702

738703
__gm__ float *out_base = reinterpret_cast<__gm__ float *>(out_t->buffer.addr) + out_t->start_offset;
739704

tests/st/a2a3/tensormap_and_ringbuffer/spmd_paged_attention/test_spmd_paged_attention.py

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@@ -9,19 +9,13 @@
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# -----------------------------------------------------------------------------------------------------------
1010
"""Paged attention unroll with TPUSH/TPOP: MIX kernel AIC+AIV cooperative pipeline."""
1111

12-
import pytest
1312
import torch
1413
from simpler.task_interface import ArgDirection as D
1514

1615
from simpler_setup import Scalar, SceneTestCase, TaskArgsBuilder, Tensor, scene_test
1716
from simpler_setup.goldens.paged_attention import compute_golden as _pa_compute_golden
1817
from simpler_setup.goldens.paged_attention import generate_inputs as _pa_generate_inputs
1918

20-
# Case1 flakily aborts with AICore error 507018 on a2a3 (the st-onboard-a2a3 job
21-
# also flakes on main, independent of the pinned pto-isa). Skipped to keep the
22-
# pto-isa pin bump green; re-enable once the 507018 paged-attention flake is fixed.
23-
pytestmark = pytest.mark.skip(reason="paged-attention flakily aborts with AICore 507018 on a2a3 (known flake)")
24-
2519

2620
@scene_test(level=2, runtime="tensormap_and_ringbuffer")
2721
class TestPagedAttentionUnrollTpushPop(SceneTestCase):

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