Redefined threading logic for WoA

Author: Harishmcw

interface/gemv.c

@@ -79,6 +79,11 @@ static inline int get_gemv_optimal_nthreads_neoversev1(BLASLONG MN, int ncpu) {
 
 static inline int get_gemv_optimal_nthreads(BLASLONG MN) {
   int ncpu = num_cpu_avail(3);
+#if defined(_WIN64) && defined(_M_ARM64)
+  if (MN > 100000000L)
+    return num_cpu_avail(4);
+  return 1;
+#endif
 #if defined(NEOVERSEV1) && !defined(COMPLEX) && !defined(DOUBLE) && !defined(BFLOAT16)
   return get_gemv_optimal_nthreads_neoversev1(MN, ncpu);
 #elif defined(DYNAMIC_ARCH) && !defined(COMPLEX) && !defined(DOUBLE) && !defined(BFLOAT16)

interface/lapack/gesv.c

@@ -117,13 +117,15 @@ int NAME(blasint *N, blasint *NRHS, FLOAT *a, blasint *ldA, blasint *ipiv,
 
 #if defined(_WIN64) && defined(_M_ARM64)
   #ifdef COMPLEX
-    if (args.m * args.n > 600)
+    if (args.m * args.n <= 300) 
   #else
-    if (args.m * args.n > 1000)
+    if (args.m * args.n <= 500) 
   #endif
-      args.nthreads = num_cpu_avail(4);
-    else
       args.nthreads = 1;
+  else if (args.m * args.n <= 1000)
+    args.nthreads = 4;
+  else
+    args.nthreads = num_cpu_avail(4);
 #else
   #ifndef DOUBLE
     if (args.m * args.n < 40000)

interface/zgemv.c

@@ -252,25 +252,30 @@ void CNAME(enum CBLAS_ORDER order,
 
 #ifdef SMP
 
-  if ( 1L * m * n < 1024L * GEMM_MULTITHREAD_THRESHOLD )
+#if defined(_WIN64) && defined(_M_ARM64)
+  if (m*n > 25000000L) 
+    nthreads = num_cpu_avail(4);
+  else
+    nthreads = 1;
+#else
+  if (1L * m * n < 1024L * GEMM_MULTITHREAD_THRESHOLD)
     nthreads = 1;
   else
     nthreads = num_cpu_avail(2);
+#endif  
 
   if (nthreads == 1) {
-#endif
+#endif  
 
     (gemv[(int)trans])(m, n, 0, alpha_r, alpha_i, a, lda, x, incx, y, incy, buffer);
 
 #ifdef SMP
-
   } else {
-
     (gemv_thread[(int)trans])(m, n, ALPHA, a, lda, x, incx, y, incy, buffer, nthreads);
-
   }
 #endif
 
+
   STACK_FREE(buffer);
 
   FUNCTION_PROFILE_END(4, m * n + m + n,  2 * m * n);