hexagon: flash attention rework (optimizations, accuracy improvements, etc) - #25085
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@lhez @ggml-org/maintainers this should be good to go. Please review and approve. |
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…, etc) (ggml-org#25085) * hex-mm: fold mm quant tasks into the main matmul threads * hex-mm: minor formatting fixes * hex-mm: cleanup is_quant checks in dma dispatch * hex-mm: fix dst-spad alignment * hex-mm: move fp kernels in the hvx-mm-kernels header * hex-mm: fuse with ADD * hex-fa: factor out ukernels into separate headers and unify the rest * hex-fa: move kernel-params compute into the host * hex-fa: refactor vtcm alloc for consistency * hex-fa: add support for FA_SELECT * hex-fa: update tracing insrumentation to cover all functions * hex-fa: update hvx fallback thresholds to recover t/g regressions * hex-fa: update tracing instrumentation * hex-fa: improved tracing with additional events * hex-fa: optimize mask processing (fastdiv, etc) * hex-fa: improve mask dma caching * hmx-fa: change loop order to maximize mask cache hits * hex-fa: remove over instrumentation * hex-fa: breakdown QKV prep trace events * hmx-fa: further mask proc optimizations * hex-fa: mask broadcast is the common case, optimize for that * hex-fa: use aligned loads where possible * hex-fa: update loops to use uint32_t indices * hmx-fa: fold vtcm init into q prep task * hex-fa: update rest of the hmx funcs to use uint32_t * hmx-fa: fold build_d into the main softmax loop * hmx-fa: start kv dmas earlier * hmx-fa: start mask dma a bit earlier * hex-fa: precompute rows per task to avoid divs * hmx-fa: specialize fa_o_store for f16 and f32 * hmx-fa: prelim support for Sinks * hmx-fa: keep softmax accumulators in fp32 * hex-fa: add tanh_f16 and exp2_f16 and use that in FA * hex-fa: use fp16 math in the hvx kernel * hex-fa: avoid expensive float -> __fp16 cast for slopes and softcap * hex-fa: replace most vec_exp_f32 with vec_exp2_f16 * hmx-fa: vectorize sinks update * hex-fa: minor formatting * hmx-fa: fold softcap loop into the tile load * hmx-fa: use vectoralias to populate sinks * hex-fa: remove redudant check * hex-fa: fix vtcm size compute to use fp32 for accumulators * hex-mm: fix trailing spaces * hmx-fa: dont use -inf to init mask to avoid conversion overflows * hex-fa: no need to explicitly guard -inf in the f16->f32 converter now * hmx-fa: cleanup fa sinks handling * hex-mm: fixed src2 stride handling when mm is fused with add * hex-fa: make lto happy
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…, etc) (ggml-org#25085) * hex-mm: fold mm quant tasks into the main matmul threads * hex-mm: minor formatting fixes * hex-mm: cleanup is_quant checks in dma dispatch * hex-mm: fix dst-spad alignment * hex-mm: move fp kernels in the hvx-mm-kernels header * hex-mm: fuse with ADD * hex-fa: factor out ukernels into separate headers and unify the rest * hex-fa: move kernel-params compute into the host * hex-fa: refactor vtcm alloc for consistency * hex-fa: add support for FA_SELECT * hex-fa: update tracing insrumentation to cover all functions * hex-fa: update hvx fallback thresholds to recover t/g regressions * hex-fa: update tracing instrumentation * hex-fa: improved tracing with additional events * hex-fa: optimize mask processing (fastdiv, etc) * hex-fa: improve mask dma caching * hmx-fa: change loop order to maximize mask cache hits * hex-fa: remove over instrumentation * hex-fa: breakdown QKV prep trace events * hmx-fa: further mask proc optimizations * hex-fa: mask broadcast is the common case, optimize for that * hex-fa: use aligned loads where possible * hex-fa: update loops to use uint32_t indices * hmx-fa: fold vtcm init into q prep task * hex-fa: update rest of the hmx funcs to use uint32_t * hmx-fa: fold build_d into the main softmax loop * hmx-fa: start kv dmas earlier * hmx-fa: start mask dma a bit earlier * hex-fa: precompute rows per task to avoid divs * hmx-fa: specialize fa_o_store for f16 and f32 * hmx-fa: prelim support for Sinks * hmx-fa: keep softmax accumulators in fp32 * hex-fa: add tanh_f16 and exp2_f16 and use that in FA * hex-fa: use fp16 math in the hvx kernel * hex-fa: avoid expensive float -> __fp16 cast for slopes and softcap * hex-fa: replace most vec_exp_f32 with vec_exp2_f16 * hmx-fa: vectorize sinks update * hex-fa: minor formatting * hmx-fa: fold softcap loop into the tile load * hmx-fa: use vectoralias to populate sinks * hex-fa: remove redudant check * hex-fa: fix vtcm size compute to use fp32 for accumulators * hex-mm: fix trailing spaces * hmx-fa: dont use -inf to init mask to avoid conversion overflows * hex-fa: no need to explicitly guard -inf in the f16->f32 converter now * hmx-fa: cleanup fa sinks handling * hex-mm: fixed src2 stride handling when mm is fused with add * hex-fa: make lto happy
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…, etc) (ggml-org#25085) * hex-mm: fold mm quant tasks into the main matmul threads * hex-mm: minor formatting fixes * hex-mm: cleanup is_quant checks in dma dispatch * hex-mm: fix dst-spad alignment * hex-mm: move fp kernels in the hvx-mm-kernels header * hex-mm: fuse with ADD * hex-fa: factor out ukernels into separate headers and unify the rest * hex-fa: move kernel-params compute into the host * hex-fa: refactor vtcm alloc for consistency * hex-fa: add support for FA_SELECT * hex-fa: update tracing insrumentation to cover all functions * hex-fa: update hvx fallback thresholds to recover t/g regressions * hex-fa: update tracing instrumentation * hex-fa: improved tracing with additional events * hex-fa: optimize mask processing (fastdiv, etc) * hex-fa: improve mask dma caching * hmx-fa: change loop order to maximize mask cache hits * hex-fa: remove over instrumentation * hex-fa: breakdown QKV prep trace events * hmx-fa: further mask proc optimizations * hex-fa: mask broadcast is the common case, optimize for that * hex-fa: use aligned loads where possible * hex-fa: update loops to use uint32_t indices * hmx-fa: fold vtcm init into q prep task * hex-fa: update rest of the hmx funcs to use uint32_t * hmx-fa: fold build_d into the main softmax loop * hmx-fa: start kv dmas earlier * hmx-fa: start mask dma a bit earlier * hex-fa: precompute rows per task to avoid divs * hmx-fa: specialize fa_o_store for f16 and f32 * hmx-fa: prelim support for Sinks * hmx-fa: keep softmax accumulators in fp32 * hex-fa: add tanh_f16 and exp2_f16 and use that in FA * hex-fa: use fp16 math in the hvx kernel * hex-fa: avoid expensive float -> __fp16 cast for slopes and softcap * hex-fa: replace most vec_exp_f32 with vec_exp2_f16 * hmx-fa: vectorize sinks update * hex-fa: minor formatting * hmx-fa: fold softcap loop into the tile load * hmx-fa: use vectoralias to populate sinks * hex-fa: remove redudant check * hex-fa: fix vtcm size compute to use fp32 for accumulators * hex-mm: fix trailing spaces * hmx-fa: dont use -inf to init mask to avoid conversion overflows * hex-fa: no need to explicitly guard -inf in the f16->f32 converter now * hmx-fa: cleanup fa sinks handling * hex-mm: fixed src2 stride handling when mm is fused with add * hex-fa: make lto happy
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Overview
The main focus here is to update
FLASH_ATTN_EXTinggml-hexagonsimilar to what I did in #24954htp/flash-atten-ops.cand removing duplicationhtp/{hvx,hmx}-fa-kernels.hSimilar to hexagon: store HMX flash-attention softmax accumulators in FP32 #24389
The PR also includes some
MUL_MATupdates as a followup to #24954.As I was looking at Flash Attention op-traces I noticed a few more things to improve in
MUL_MAT.Technically, I could split that up but I did extensive testing of the combined update.
Additional information
Tested on all supported devices.
Newer devices show higher gains but there are steady improvements across the board
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