Use 2D thread distribution for small GEMMs.

Allows maximum use of available cores if one of M and N is small and the other is large.
This commit is contained in:
Tim Moon 2017-10-03 13:43:39 -07:00
parent a89d6711c6
commit 860dcfc703
1 changed files with 63 additions and 33 deletions

View File

@ -219,12 +219,14 @@ static int inner_thread(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n,
FLOAT *buffer[DIVIDE_RATE];
BLASLONG k, lda, ldb, ldc;
BLASLONG m_from, m_to, n_from, n_to, N_from, N_to;
BLASLONG m_from, m_to, n_from, n_to;
FLOAT *alpha, *beta;
FLOAT *a, *b, *c;
job_t *job = (job_t *)args -> common;
BLASLONG nthreads_m;
BLASLONG xxx, bufferside;
BLASLONG mypos_m, mypos_n;
BLASLONG ls, min_l, jjs, min_jj;
BLASLONG is, min_i, div_n;
@ -259,26 +261,28 @@ static int inner_thread(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n,
alpha = (FLOAT *)args -> alpha;
beta = (FLOAT *)args -> beta;
nthreads_m = args -> nthreads;
if (range_m) {
nthreads_m = range_m[-1];
}
mypos_m = mypos % nthreads_m;
mypos_n = mypos / nthreads_m;
m_from = 0;
m_to = M;
if (range_m) {
m_from = range_m[0];
m_to = range_m[1];
m_from = range_m[mypos_m + 0];
m_to = range_m[mypos_m + 1];
}
n_from = 0;
n_to = N;
N_from = 0;
N_to = N;
if (range_n) {
n_from = range_n[mypos + 0];
n_to = range_n[mypos + 1];
N_from = range_n[0];
N_to = range_n[args -> nthreads];
}
if (beta) {
@ -287,7 +291,7 @@ static int inner_thread(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n,
#else
if ((beta[0] != ONE) || (beta[1] != ZERO))
#endif
BETA_OPERATION(m_from, m_to, N_from, N_to, beta, c, ldc);
BETA_OPERATION(m_from, m_to, range_n[mypos_n * nthreads_m], range_n[(mypos_n + 1) * nthreads_m], beta, c, ldc);
}
if ((k == 0) || (alpha == NULL)) return 0;
@ -299,8 +303,8 @@ static int inner_thread(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n,
) return 0;
#if 0
fprintf(stderr, "Thread[%ld] m_from : %ld m_to : %ld n_from : %ld n_to : %ld N_from : %ld N_to : %ld\n",
mypos, m_from, m_to, n_from, n_to, N_from, N_to);
fprintf(stderr, "Thread[%ld] m_from : %ld m_to : %ld n_from : %ld n_to : %ld\n",
mypos, m_from, m_to, n_from, n_to);
fprintf(stderr, "GEMM: P = %4ld Q = %4ld R = %4ld\n", (BLASLONG)GEMM_P, (BLASLONG)GEMM_Q, (BLASLONG)GEMM_R);
@ -394,7 +398,8 @@ static int inner_thread(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n,
}
#endif
for (i = 0; i < args -> nthreads; i++) job[mypos].working[i][CACHE_LINE_SIZE * bufferside] = (BLASLONG)buffer[bufferside];
for (i = mypos_n * nthreads_m; i < (mypos_n + 1) * nthreads_m; i++)
job[mypos].working[i][CACHE_LINE_SIZE * bufferside] = (BLASLONG)buffer[bufferside];
WMB;
}
@ -402,13 +407,13 @@ static int inner_thread(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n,
do {
current ++;
if (current >= args -> nthreads) current = 0;
if (current >= (mypos_n + 1) * nthreads_m) current = mypos_n * nthreads_m;
div_n = (range_n[current + 1] - range_n[current] + DIVIDE_RATE - 1) / DIVIDE_RATE;
for (xxx = range_n[current], bufferside = 0; xxx < range_n[current + 1]; xxx += div_n, bufferside ++) {
if (current != mypos) {
if (current != mypos) {
START_RPCC();
@ -479,7 +484,7 @@ static int inner_thread(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n,
}
current ++;
if (current >= args -> nthreads) current = 0;
if (current >= (mypos_n + 1) * nthreads_m) current = mypos_n * nthreads_m;
} while (current != mypos);
@ -525,7 +530,8 @@ static int inner_thread(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n,
}
static int gemm_driver(blas_arg_t *args, BLASLONG *range_m, BLASLONG
*range_n, FLOAT *sa, FLOAT *sb, BLASLONG mypos){
*range_n, FLOAT *sa, FLOAT *sb,
BLASLONG nthreads_m, BLASLONG nthreads_n) {
blas_arg_t newarg;
@ -537,8 +543,10 @@ static int gemm_driver(blas_arg_t *args, BLASLONG *range_m, BLASLONG
blas_queue_t queue[MAX_CPU_NUMBER];
BLASLONG range_M[MAX_CPU_NUMBER + 1];
BLASLONG range_N[MAX_CPU_NUMBER + 1];
BLASLONG range_M_buffer[MAX_CPU_NUMBER + 2];
BLASLONG range_N_buffer[MAX_CPU_NUMBER + 2];
BLASLONG *range_M = range_M_buffer + 1;
BLASLONG *range_N = range_N_buffer + 1;
BLASLONG num_cpu_m, num_cpu_n;
@ -595,6 +603,9 @@ static int gemm_driver(blas_arg_t *args, BLASLONG *range_m, BLASLONG
newarg.gemm_r = args -> gemm_r;
#endif
range_M[-1] = nthreads_m;
range_N[-1] = nthreads_n;
if (!range_m) {
range_M[0] = 0;
m = args -> m;
@ -607,7 +618,7 @@ static int gemm_driver(blas_arg_t *args, BLASLONG *range_m, BLASLONG
while (m > 0){
width = blas_quickdivide(m + nthreads - num_cpu_m - 1, nthreads - num_cpu_m);
width = blas_quickdivide(m + nthreads_m - num_cpu_m - 1, nthreads_m - num_cpu_m);
m -= width;
if (m < 0) width = width + m;
@ -617,12 +628,16 @@ static int gemm_driver(blas_arg_t *args, BLASLONG *range_m, BLASLONG
num_cpu_m ++;
}
for (i = 0; i < num_cpu_m; i++) {
for (i = num_cpu_m; i < MAX_CPU_NUMBER; i++) {
range_M[i + 1] = range_M[num_cpu_m];
}
for (i = 0; i < nthreads; i++) {
queue[i].mode = mode;
queue[i].routine = inner_thread;
queue[i].args = &newarg;
queue[i].range_m = &range_M[i];
queue[i].range_n = &range_N[0];
queue[i].range_m = range_M;
queue[i].range_n = range_N;
queue[i].sa = NULL;
queue[i].sb = NULL;
queue[i].next = &queue[i + 1];
@ -659,17 +674,21 @@ static int gemm_driver(blas_arg_t *args, BLASLONG *range_m, BLASLONG
num_cpu_n ++;
}
for (j = 0; j < num_cpu_m; j++) {
for (i = 0; i < num_cpu_m; i++) {
for (j = num_cpu_n; j < MAX_CPU_NUMBER; j++) {
range_N[j + 1] = range_N[num_cpu_n];
}
for (j = 0; j < MAX_CPU_NUMBER; j++) {
for (i = 0; i < MAX_CPU_NUMBER; i++) {
for (k = 0; k < DIVIDE_RATE; k++) {
job[j].working[i][CACHE_LINE_SIZE * k] = 0;
}
}
}
queue[num_cpu_m - 1].next = NULL;
queue[nthreads - 1].next = NULL;
exec_blas(num_cpu_m, queue);
exec_blas(nthreads, queue);
}
#ifdef USE_ALLOC_HEAP
@ -684,6 +703,7 @@ int CNAME(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n, FLOAT *sa, FLO
BLASLONG m = args -> m;
BLASLONG n = args -> n;
BLASLONG nthreads = args -> nthreads;
BLASLONG nthreads_m, nthreads_n;
if (nthreads == 1) {
GEMM_LOCAL(args, range_m, range_n, sa, sb, 0);
@ -704,21 +724,31 @@ int CNAME(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n, FLOAT *sa, FLO
n = n_to - n_from;
}
if ((m < 2 * SWITCH_RATIO) || (n < 2 * SWITCH_RATIO)) {
nthreads_m = nthreads;
while (m < nthreads_m * SWITCH_RATIO) {
nthreads_m = nthreads_m / 2;
}
if (nthreads_m < 1) {
GEMM_LOCAL(args, range_m, range_n, sa, sb, 0);
return 0;
}
if (m < nthreads * SWITCH_RATIO) {
nthreads = blas_quickdivide(m, SWITCH_RATIO);
nthreads_n = nthreads / nthreads_m;
if (n < nthreads_m * (nthreads_n - 1)) {
nthreads_n = (n + nthreads_m - 1) / nthreads_m;
}
if (n < nthreads * SWITCH_RATIO) {
nthreads = blas_quickdivide(n, SWITCH_RATIO);
nthreads = nthreads_m * nthreads_n;
if (nthreads <= 1) {
GEMM_LOCAL(args, range_m, range_n, sa, sb, 0);
return 0;
}
args -> nthreads = nthreads;
gemm_driver(args, range_m, range_n, sa, sb, 0);
gemm_driver(args, range_m, range_n, sa, sb, nthreads_m, nthreads_n);
return 0;
}