Updated 6.4 schedule to improve wave FAv3 perf (#788)

* added unrolling
* updated priority order
* tested with reduced VGPRs spills 
* reordered prefetch compute in cluster 1 and 3.

---------

Signed-off-by: root <[email protected]>
Signed-off-by: xintin <[email protected]>

Author: xintin

examples/python/6.4_schedule.py

@@ -39,26 +39,27 @@
 """
 
 import math
+
 import torch
+from utils import list_tests, parse_args, run_test
 
+import wave_lang.kernel.lang as tkl
 import wave_lang.kernel.wave as tkw
 from wave_lang.kernel.lang.global_symbols import *
 from wave_lang.kernel.lang.wave_types import *
 from wave_lang.kernel.wave.compile import WaveCompileOptions, wave_compile
-from wave_lang.kernel.wave.utils.run_utils import set_default_run_config
+from wave_lang.kernel.wave.schedules.attention_prefetch import (
+    get_attention_prefetch_schedule,
+)
 from wave_lang.kernel.wave.scheduling.schedule import SchedulingType
-from wave_lang.kernel.wave.utils.general_utils import get_default_scheduling_params
 
 # Import templates and schedules
 from wave_lang.kernel.wave.templates.attention_common import AttentionShape
 from wave_lang.kernel.wave.templates.tagged_attention import (
     get_tagged_bshd_attention_kernel,
 )
-from wave_lang.kernel.wave.schedules.attention_prefetch import (
-    get_attention_prefetch_schedule,
-)
-
-from utils import parse_args, list_tests, run_test
+from wave_lang.kernel.wave.utils.general_utils import get_default_scheduling_params
+from wave_lang.kernel.wave.utils.run_utils import set_default_run_config
 
 
 def test_attention_manual_schedule(is_debug=False):
@@ -85,10 +86,10 @@ def test_attention_manual_schedule(is_debug=False):
     shape = AttentionShape(
         num_query_heads=64,
         num_kv_heads=64,
-        query_seq_len=128,
-        head_size_kv=64,
-        head_size=64,
-        kv_seq_len=256,
+        query_seq_len=16384,
+        head_size_kv=128,
+        head_size=128,
+        kv_seq_len=16384,
     )
     mfma_variant = (tkw.MMAType.F32_16x16x16_F16,) * 2
 
@@ -102,6 +103,10 @@ def test_attention_manual_schedule(is_debug=False):
     )
     hyperparams.update(get_default_scheduling_params())
 
+    # set the unroll factor
+    UNROLL_FACTOR = tkl.sym.UNROLL_FACTOR
+    hyperparams[UNROLL_FACTOR] = 4
+
     # Get the prefetch schedule
     attention_prefetch_schedule = get_attention_prefetch_schedule()
 
@@ -111,6 +116,17 @@ def test_attention_manual_schedule(is_debug=False):
         schedule=SchedulingType.MANUAL,
         use_global_to_shared=True,  # Enable GatherToLDS
         print_ir_after="all" if is_debug else [],
+        use_buffer_ops=True,
+        postprocess="""
+        module attributes {transform.with_named_sequence} {
+            transform.named_sequence @__transform_main(%arg0: !transform.any_op {transform.readonly}) {
+                %0 = transform.structured.match ops{["scf.for"]} in %arg0 : (!transform.any_op) -> !transform.any_op
+                transform.loop.unroll %0 { factor = %%UNROLL_FACTOR%% } : !transform.any_op
+                transform.yield
+            }
+        }
+        """,
+        linearize_shared_access=False,  # This impacts the VGPR spills
     )
 
     options = set_default_run_config(options)

wave_lang/kernel/wave/schedules/attention_prefetch.py

@@ -240,45 +240,41 @@ def attention_prefetch_schedule():
         # - Cluster 2: PV computation + softmax0
         # - Cluster 3: V data movement + local load K
         clusters = [
-            # Cluster 0: QK computation and softmax1
+            # Cluster 0: QK computation and softmax1 (high priority through barrier)
             tkw.cluster(
                 [
                     tkw.SetWavePrio(1),
                     mma_qk_init_kernel,
                     mma_qk_kernel,
-                    tkw.SetWavePrio(0),
                     *softmax1_ops_kernel,
                     tkw.WorkgroupBarrier(),
-                    tkw.SchedulingBarrier([]),
+                    tkw.SetWavePrio(0),  # Lower priority after barrier
                 ],
             ),
             # Cluster 1: K data movement (global_to_shared_k) + local load V
             tkw.cluster(
                 [
-                    global_to_shared_k_kernel,
                     shared_load_v_kernel,
+                    global_to_shared_k_kernel,
                     tkw.WorkgroupBarrier(),
-                    tkw.SchedulingBarrier([]),
                 ],
             ),
-            # Cluster 2: PV computation and softmax0
+            # Cluster 2: PV computation and softmax0 (high priority through barrier)
             tkw.cluster(
                 [
                     tkw.SetWavePrio(1),
                     mma_pv_kernel,
-                    tkw.SetWavePrio(0),
                     *softmax0_ops_kernel,
                     tkw.WorkgroupBarrier(),
-                    tkw.SchedulingBarrier([]),
+                    tkw.SetWavePrio(0),
                 ],
             ),
             # Cluster 3: V data movement (global_to_shared_v) + local load K
             tkw.cluster(
                 [
-                    global_to_shared_v_kernel,
                     shared_load_k_kernel,
+                    global_to_shared_v_kernel,
                     tkw.WorkgroupBarrier(),
-                    tkw.SchedulingBarrier([]),
                 ],
             ),
         ]