Support unpad layout for group lse

example/ck_tile/01_fmha/fmha_fwd.cpp

@@ -479,16 +479,18 @@ bool run(const ck_tile::ArgParser& arg_parser)
             : std::array<ck_tile::index_t, 2>{1, 1});
 
     ck_tile::HostTensor<LSEDataType> lse_acc_host(
-        1 < num_splits ? std::array<ck_tile::index_t, 4>{num_splits, batch, nhead, max_seqlen_q}
-                       : std::array<ck_tile::index_t, 4>{1, 1, 1, 1});
+        1 < num_splits
+            ? std::array<ck_tile::index_t, 4>{num_splits, shape_batch, nhead, shape_seqlen_q}
+            : std::array<ck_tile::index_t, 4>{1, 1, 1, 1});
     ck_tile::HostTensor<OaccDataType> o_acc_host(
         1 < num_splits
             ? std::array<ck_tile::index_t, 5>{num_splits, batch, nhead, max_seqlen_q, hdim_v}
             : std::array<ck_tile::index_t, 5>{1, 1, 1, 1, 1});
 
-    // self define lse data layout as [batch, nhead, max_seqlen_q]
+    // batch mode of lse data layout is [batch, nhead, max_seqlen_q]
+    // group mode of lse data layout is [nhead, total_seqlen_q]
     ck_tile::HostTensor<LSEDataType> lse_host(
-        lse ? std::array<ck_tile::index_t, 3>{batch, nhead, max_seqlen_q}
+        lse ? std::array<ck_tile::index_t, 3>{shape_batch, nhead, shape_seqlen_q}
             : std::array<ck_tile::index_t, 3>{1, 1, 1} /* dummy shape for simplifying code */);
 
     ck_tile::HostTensor<ODataType> o_host(
@@ -669,8 +671,8 @@ bool run(const ck_tile::ArgParser& arg_parser)
         const ck_tile::index_t nhead_stride_bias =
             (i_perm ? 0 * shape_seqlen_q * shape_seqlen_k : 0 * shape_seqlen_k);
         const ck_tile::index_t nhead_stride_randval = (shape_seqlen_q * max_seqlen_k);
-        const ck_tile::index_t nhead_stride_lse     = max_seqlen_q;
-        const ck_tile::index_t nhead_stride_lse_acc = max_seqlen_q;
+        const ck_tile::index_t nhead_stride_lse     = shape_seqlen_q;
+        const ck_tile::index_t nhead_stride_lse_acc = shape_seqlen_q;
         const ck_tile::index_t nhead_stride_o_acc   = (max_seqlen_q * hdim_v);
         const ck_tile::index_t nhead_stride_o       = (o_perm ? shape_seqlen_q * hdim_v : hdim_v);
         // setup batch_stride_* arguments
@@ -679,12 +681,12 @@ bool run(const ck_tile::ArgParser& arg_parser)
         const ck_tile::index_t batch_stride_v       = (nhead_k * hdim_v * shape_seqlen_k);
         const ck_tile::index_t batch_stride_bias    = (0 * nhead * shape_seqlen_q * shape_seqlen_k);
         const ck_tile::index_t batch_stride_randval = (nhead * shape_seqlen_q * max_seqlen_k);
-        const ck_tile::index_t batch_stride_lse     = (nhead * max_seqlen_q);
-        const ck_tile::index_t batch_stride_lse_acc = (nhead * max_seqlen_q);
+        const ck_tile::index_t batch_stride_lse     = (nhead * shape_seqlen_q);
+        const ck_tile::index_t batch_stride_lse_acc = (nhead * shape_seqlen_q);
         const ck_tile::index_t batch_stride_o_acc   = (nhead * max_seqlen_q * hdim_v);
         const ck_tile::index_t batch_stride_o       = (nhead * shape_seqlen_q * hdim_v);
         // setup split_stride_* arguments (only used in split-kv kernel)
-        const ck_tile::index_t split_stride_lse_acc = (batch * nhead * max_seqlen_q);
+        const ck_tile::index_t split_stride_lse_acc = (batch * nhead * shape_seqlen_q);
         const ck_tile::index_t split_stride_o_acc   = (batch * nhead * max_seqlen_q * hdim_v);
 
         return fmha_fwd_args{q_buf.GetDeviceBuffer(),
@@ -996,8 +998,9 @@ bool run(const ck_tile::ArgParser& arg_parser)
         if(lse)
         {
             ck_tile::HostTensor<SMPLComputeDataType> lse_host_result({nhead, real_seqlen_q});
-            lse_host_result.ForEach(
-                [&](auto& self, auto idx) { self(idx) = lse_host(wb, idx[0], idx[1]); });
+            lse_host_result.ForEach([&](auto& self, auto idx) {
+                self(idx) = lse_host(b, idx[0], idx[1] + query_offset);
+            });
 
             cur_pass = ck_tile::check_err(lse_host_result,
                                           lse_host_ref,

example/ck_tile/01_fmha/fmha_fwd.hpp

@@ -185,7 +185,6 @@ auto fmha_fwd_create_kargs_and_grids(fmha_fwd_args args)
                                          args.nhead_stride_randval,
                                          args.nhead_stride_lse,
                                          args.nhead_stride_o,
-                                         args.batch_stride_lse,
                                          args.window_size_left,
                                          args.window_size_right,
                                          args.mask_type,

include/ck_tile/ops/fmha/kernel/fmha_fwd_kernel.hpp

@@ -86,7 +86,7 @@ struct FmhaFwdKernel
             "w" + _TS_(gwt::at(ck_tile::number<0>{})) + "x" + _TS_(gwt::at(ck_tile::number<1>{})) + "x" + _TS_(gwt::at(ck_tile::number<2>{})) + "_" +
             (kBlockPerCuInput == -1 ? "" : ("o" + _TS_(kBlockPerCu) + "_")) + _SS_(FmhaPipeline::name) + "_" +
             "v" + (std::is_same_v<VLayout, ck_tile::tensor_layout::gemm::RowMajor> ? "r" : "c") + (pn.empty() ? "" : "_" + pn) +
-            (BiasEnum == BlockAttentionBiasEnum::NO_BIAS ? _SS_("") : (_SS_("_") + BlockAttentionBiasEnumToStr<BiasEnum>::name)) + 
+            (BiasEnum == BlockAttentionBiasEnum::NO_BIAS ? _SS_("") : (_SS_("_") + BlockAttentionBiasEnumToStr<BiasEnum>::name)) +
             (kHasMask ? "_" + _SS_(FmhaMask::name) : "") + (kStoreLSE ? "_lse" : "" ) + (kHasDropout ? "_dropout" : "" ) + (kDoFp8StaticQuant ? "_squant" : "" );
         #undef _SS_
         #undef _TS_
@@ -387,7 +387,6 @@ struct FmhaFwdKernel
               ck_tile::index_t nhead_stride_randval,
               ck_tile::index_t nhead_stride_lse,
               ck_tile::index_t nhead_stride_o,
-              ck_tile::index_t batch_stride_lse,
               ck_tile::index_t window_size_left,
               ck_tile::index_t window_size_right,
               ck_tile::index_t mask_type,
@@ -448,7 +447,6 @@ struct FmhaFwdKernel
         {
             kargs.lse_ptr          = lse_ptr;
             kargs.nhead_stride_lse = nhead_stride_lse;
-            kargs.batch_stride_lse = batch_stride_lse;
         }
         if constexpr(kDoFp8StaticQuant)
         {
@@ -524,7 +522,7 @@ struct FmhaFwdKernel
             }
             if constexpr(kStoreLSE)
             {
-                batch_offset_lse = static_cast<long_index_t>(i_batch) * kargs.batch_stride_lse;
+                batch_offset_lse = query_start;
             }
             if constexpr(kHasDropout)
             {