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submission 657324

Yufeng98 · python · License unknown

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No package. Vendor the mirrored source: 131 lines, June 9 Researcher Reciprocity License v1.0.

submission.py
curl "https://kernelindex.com/api/v1/implementations/kernelbot-amd-mixed-mla-657324?include=source"
interfacepython
Compatibility
measured onAMD Instinct MI355X
declared hardwareAMD Instinct MI355X
architecturesgfx950
dtypesbf16, int32

Benchmark evidence

1 measurement across 1 GPU, fastest first.

Operation / workload
Hardware
Latency
Rank
Observed
AMD Instinct MI355X
34.8µs
#66 of 766
2026-03-28

Reported · How evidence levels are derived →

Source and license

sourceavailable
revision digestsha256:f096af6127b62ff22627860f39369a4c65aba6ba3238aabe062a5d87afb56131
license declaredunknown
license concludedunknown
authorsYufeng98
imported2026-08-15

Kernel source

submission.py131 lines
#!POPCORN leaderboard amd-mixed-mla
#!POPCORN gpu MI355X
"""
v578: ps=2 for (64,1024)/(256,1024) with eager init ALL shapes.

Same config as v577 but eliminates lazy init — ALL shapes including ps>1
are eagerly initialized at module level to avoid first-call overhead
that caused v577 to timeout in ranked mode (12 min limit).
"""
import weakref
import torch
from task import input_t, output_t
from aiter import dtypes as aiter_dtypes
from aiter import get_mla_metadata_info_v1, get_mla_metadata_v1
from aiter import mla_decode_stage1_asm_fwd, mla_reduce_v1

_USE_STATIC = False
try:
    from aiter.ops.quant import static_per_tensor_quant
    _USE_STATIC = True
except ImportError:
    pass
from aiter.ops.quant import dynamic_per_tensor_quant

FP8_DTYPE = aiter_dtypes.fp8
NUM_HEADS = 16; NUM_KV_HEADS = 1; QK_HEAD_DIM = 576; V_HEAD_DIM = 512
SM_SCALE = 1.0 / (QK_HEAD_DIM ** 0.5)
_STATIC_SCALE = torch.tensor([0.1], dtype=torch.float32, device='cuda')

_CFG = {
    (4,1024): {'ps':1, 'splits':5},
    (32,1024): {'ps':1, 'splits':5},
    (4,8192): {'ps':8, 'splits':12},
    (32,8192): {'ps':8, 'splits':12},
    (64,1024): {'ps':2, 'splits':8},
    (64,8192): {'ps':8, 'splits':12},
    (256,1024): {'ps':2, 'splits':4},
    (256,8192): {'ps':8, 'splits':8},
}

_gqf = {}; _gqs = {}
for (bs, kv) in _CFG:
    _gqf[(bs, kv)] = torch.empty((bs, NUM_HEADS, QK_HEAD_DIM), dtype=FP8_DTYPE, device='cuda')
    _gqs[(bs, kv)] = _STATIC_SCALE.clone()
_go = torch.empty((256, NUM_HEADS, V_HEAD_DIM), dtype=torch.bfloat16, device='cuda')
_gqo = torch.arange(257, dtype=torch.int32, device='cuda')

# Per-shape scratch buffers for direct stage1+reduce
_g_logits = {}
_g_attn_lse = {}

# Eagerly initialize ALL shapes (including ps>1)
_gsw = {}
for (bs, kv), cfg in sorted(_CFG.items()):
    ps = cfg['ps']; splits = cfg['splits']
    total_kv = bs * kv
    info = get_mla_metadata_info_v1(bs, 1, NUM_HEADS, FP8_DTYPE, FP8_DTYPE,
        is_sparse=False, fast_mode=False, num_kv_splits=splits, intra_batch_mode=True)
    work = [torch.zeros(s, dtype=t, device='cuda') for s, t in info]
    wm, wi, wis, ri, rfm, rpm = work
    if ps == 1:
        kip = torch.arange(bs + 1, dtype=torch.int32, device='cuda') * kv
        kvi = torch.arange(total_kv, dtype=torch.int32, device='cuda')
        kvlpl = torch.ones(bs, dtype=torch.int32, device='cuda')
    else:
        kip = torch.arange(bs + 1, dtype=torch.int32, device='cuda') * (kv // ps)
        kvi = torch.arange(total_kv // ps, dtype=torch.int32, device='cuda')
        kvlpl = torch.full((bs,), ps, dtype=torch.int32, device='cuda')
    kl = (kip[1:] - kip[:-1]).to(torch.int32)
    qoi = torch.arange(bs + 1, dtype=torch.int32, device='cuda')
    get_mla_metadata_v1(qoi, kip, kl,
        NUM_HEADS // NUM_KV_HEADS, NUM_KV_HEADS, True,
        wm, wis, wi, ri, rfm, rpm,
        page_size=ps, kv_granularity=max(ps, 16), max_seqlen_qo=1, uni_seqlen_qo=1,
        fast_mode=False, max_split_per_batch=splits,
        intra_batch_mode=True, dtype_q=FP8_DTYPE, dtype_kv=FP8_DTYPE)
    _gsw[(bs, kv)] = (work, kip, kvi, kvlpl, ps, splits)
    n_partial = rpm.size(0)
    _g_logits[(bs, kv)] = torch.empty((n_partial, 1, NUM_HEADS, V_HEAD_DIM), dtype=torch.float32, device='cuda')
    _g_attn_lse[(bs, kv)] = torch.empty((n_partial, 1, NUM_HEADS, 1), dtype=torch.float32, device='cuda')

_q_cache = {}


def custom_kernel(data: input_t) -> output_t:
    q, kv_data, qo_indptr, kv_indptr, config = data
    bs = config['batch_size']; kvsl = config['kv_seq_len']
    tq = q.shape[0]; sk = (bs, kvsl)
    kvf, kvs = kv_data['fp8']
    tkv = kvf.shape[0]; kd = kvf.shape[-1]

    wl, kip, kvi, kvlpl, ps, ns = _gsw[sk]
    wm, wi, wis, ri, rfm, rpm = wl
    qf = _gqf[sk]; qs = _gqs[sk]
    kv4d = kvf.view(tkv // ps, ps, NUM_KV_HEADS, kd)

    q_ptr = q.data_ptr()
    q_ver = q._version if hasattr(q, '_version') else -1
    cached = _q_cache.get(sk)
    hit = cached is not None and cached[0]() is q and cached[1] == q_ptr and cached[2] == q_ver
    if not hit:
        if _USE_STATIC:
            static_per_tensor_quant(qf, q, _STATIC_SCALE)
        else:
            dynamic_per_tensor_quant(qf, q, qs)
        _q_cache[sk] = (weakref.ref(q), q_ptr, q_ver)

    # Direct stage1+reduce
    logits = _g_logits[sk]
    attn_lse = _g_attn_lse[sk]

    mla_decode_stage1_asm_fwd(
        qf, kv4d, _gqo, kip, kvi, kvlpl,
        None,  # num_kv_splits_indptr
        wm, wi, wis,
        1,     # max_seqlen_q
        ps, NUM_KV_HEADS, SM_SCALE,
        logits, attn_lse, _go,
        qs, kvs,
    )

    mla_reduce_v1(
        logits, attn_lse,
        ri, rfm, rpm,
        1,     # max_seqlen_q
        _go,
        None,  # final_lse
    )

    return _go[:tq]
scrolls · 131 lines total

Source code from GPU Mode and the KernelBot dataset · June 9 Researcher Reciprocity License v1.0

Best evidence level for this revision: reported

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