extern "C" magma_int_t
magma_sgeqrf2_gpu(
magma_int_t m, magma_int_t n,
magmaFloat_ptr dA, size_t dA_offset, magma_int_t ldda,
float *tau,
magma_queue_t* queue,
magma_int_t *info)
{
/* -- clMAGMA (version 1.3.0) --
Univ. of Tennessee, Knoxville
Univ. of California, Berkeley
Univ. of Colorado, Denver
@date November 2014
Purpose
=======
SGEQRF computes a QR factorization of a real M-by-N matrix A:
A = Q * R.
Arguments
=========
M (input) INTEGER
The number of rows of the matrix A. M >= 0.
N (input) INTEGER
The number of columns of the matrix A. N >= 0.
dA (input/output) REAL array on the GPU, dimension (LDDA,N)
On entry, the M-by-N matrix A.
On exit, the elements on and above the diagonal of the array
contain the min(M,N)-by-N upper trapezoidal matrix R (R is
upper triangular if m >= n); the elements below the diagonal,
with the array TAU, represent the orthogonal matrix Q as a
product of min(m,n) elementary reflectors (see Further
Details).
LDDA (input) INTEGER
The leading dimension of the array dA. LDDA >= max(1,M).
To benefit from coalescent memory accesses LDDA must be
divisible by 16.
TAU (output) REAL array, dimension (min(M,N))
The scalar factors of the elementary reflectors (see Further
Details).
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
or another error occured, such as memory allocation failed.
Further Details
===============
The matrix Q is represented as a product of elementary reflectors
Q = H(1) H(2) . . . H(k), where k = min(m,n).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a real scalar, and v is a real vector with
v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i),
and tau in TAU(i).
===================================================================== */
#define dA(a_1,a_2) dA, (dA_offset + (a_1) + (a_2)*(ldda))
#define work(a_1) ( work + (a_1))
#define hwork ( work + (nb)*(m))
magmaFloat_ptr dwork;
float *work;
magma_int_t i, k, ldwork, lddwork, old_i, old_ib, rows;
magma_int_t nbmin, nx, ib, nb;
magma_int_t lhwork, lwork;
*info = 0;
if (m < 0) {
*info = -1;
} else if (n < 0) {
*info = -2;
} else if (ldda < max(1,m)) {
*info = -4;
}
if (*info != 0) {
magma_xerbla( __func__, -(*info) );
return *info;
}
k = min(m,n);
if (k == 0)
return *info;
nb = magma_get_sgeqrf_nb(m);
lwork = (m+n) * nb;
lhwork = lwork - (m)*nb;
if ( MAGMA_SUCCESS != magma_smalloc( &dwork, n*nb )) {
*info = MAGMA_ERR_DEVICE_ALLOC;
return *info;
}
/*
if ( MAGMA_SUCCESS != magma_smalloc_cpu( &work, lwork ) ) {
*info = MAGMA_ERR_HOST_ALLOC;
magma_free( dwork );
return *info;
}
*/
cl_mem buffer = clCreateBuffer(gContext, CL_MEM_READ_WRITE | CL_MEM_ALLOC_HOST_PTR,
sizeof(float)*lwork, NULL, NULL);
work = (float*)clEnqueueMapBuffer(queue[0], buffer, CL_TRUE,
CL_MAP_READ | CL_MAP_WRITE,
0, lwork*sizeof(float),
0, NULL, NULL, NULL);
nbmin = 2;
nx = nb;
ldwork = m;
lddwork= n;
if (nb >= nbmin && nb < k && nx < k) {
/* Use blocked code initially */
old_i = 0; old_ib = nb;
for (i = 0; i < k-nx; i += nb) {
ib = min(k-i, nb);
rows = m -i;
magma_queue_sync( queue[1] );
magma_sgetmatrix_async(rows, ib, dA(i, i), ldda, work(i), ldwork, queue[0], NULL);
if (i > 0) {
/* Apply H' to A(i:m,i+2*ib:n) from the left */
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
m-old_i, n-old_i-2*old_ib, old_ib,
dA(old_i, old_i ), ldda, dwork,0, lddwork,
dA(old_i, old_i+2*old_ib), ldda, dwork,old_ib, lddwork, queue[1]);
magma_ssetmatrix_async( old_ib, old_ib, work(old_i), ldwork,
dA(old_i, old_i), ldda, queue[1], NULL);
}
magma_queue_sync(queue[0]);
lapackf77_sgeqrf(&rows, &ib, work(i), &ldwork, tau+i, hwork, &lhwork, info);
/* Form the triangular factor of the block reflector
H = H(i) H(i+1) . . . H(i+ib-1) */
lapackf77_slarft( MagmaForwardStr, MagmaColumnwiseStr,
&rows, &ib,
work(i), &ldwork, tau+i, hwork, &ib);
spanel_to_q( MagmaUpper, ib, work(i), ldwork, hwork+ib*ib );
/* download the i-th V matrix */
magma_ssetmatrix_async(rows, ib, work(i), ldwork, dA(i,i), ldda, queue[0], NULL);
/* download the T matrix */
magma_queue_sync( queue[1] );
magma_ssetmatrix_async( ib, ib, hwork, ib, dwork, 0, lddwork, queue[0], NULL);
magma_queue_sync( queue[0] );
if (i + ib < n) {
if (i+nb < k-nx) {
/* Apply H' to A(i:m,i+ib:i+2*ib) from the left */
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
rows, ib, ib,
dA(i, i ), ldda, dwork,0, lddwork,
dA(i, i+ib), ldda, dwork,ib, lddwork, queue[1]);
sq_to_panel( MagmaUpper, ib, work(i), ldwork, hwork+ib*ib );
}
else {
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
rows, n-i-ib, ib,
dA(i, i ), ldda, dwork,0, lddwork,
dA(i, i+ib), ldda, dwork,ib, lddwork, queue[1]);
sq_to_panel( MagmaUpper, ib, work(i), ldwork, hwork+ib*ib );
magma_ssetmatrix_async(ib, ib, work(i), ldwork, dA(i,i), ldda, queue[1], NULL);
}
old_i = i;
old_ib = ib;
}
}
} else {
i = 0;
}
magma_free(dwork);
/* Use unblocked code to factor the last or only block. */
if (i < k) {
ib = n-i;
rows = m-i;
magma_sgetmatrix_async(rows, ib, dA(i, i), ldda, work, rows, queue[1], NULL);
magma_queue_sync(queue[1]);
lhwork = lwork - rows*ib;
lapackf77_sgeqrf(&rows, &ib, work, &rows, tau+i, work+ib*rows, &lhwork, info);
magma_ssetmatrix_async(rows, ib, work, rows, dA(i, i), ldda, queue[1], NULL);
}
magma_queue_sync(queue[0]);
magma_queue_sync(queue[1]);
// magma_free_cpu(work);
clEnqueueUnmapMemObject(queue[0], buffer, work, 0, NULL, NULL);
clReleaseMemObject(buffer);
return *info;
} /* magma_sgeqrf2_gpu */
extern "C" magma_int_t
magma_sgeqrf2_mgpu( magma_int_t num_gpus, magma_int_t m, magma_int_t n,
float **dlA, magma_int_t ldda,
float *tau,
magma_int_t *info )
{
/* -- MAGMA (version 1.3.0) --
Univ. of Tennessee, Knoxville
Univ. of California, Berkeley
Univ. of Colorado, Denver
November 2012
Purpose
=======
SGEQRF2_MGPU computes a QR factorization of a real M-by-N matrix A:
A = Q * R. This is a GPU interface of the routine.
Arguments
=========
M (input) INTEGER
The number of rows of the matrix A. M >= 0.
N (input) INTEGER
The number of columns of the matrix A. N >= 0.
dA (input/output) REAL array on the GPU, dimension (LDDA,N)
On entry, the M-by-N matrix dA.
On exit, the elements on and above the diagonal of the array
contain the min(M,N)-by-N upper trapezoidal matrix R (R is
upper triangular if m >= n); the elements below the diagonal,
with the array TAU, represent the orthogonal matrix Q as a
product of min(m,n) elementary reflectors (see Further
Details).
LDDA (input) INTEGER
The leading dimension of the array dA. LDDA >= max(1,M).
To benefit from coalescent memory accesses LDDA must be
dividable by 16.
TAU (output) REAL array, dimension (min(M,N))
The scalar factors of the elementary reflectors (see Further
Details).
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
or another error occured, such as memory allocation failed.
Further Details
===============
The matrix Q is represented as a product of elementary reflectors
Q = H(1) H(2) . . . H(k), where k = min(m,n).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a real scalar, and v is a real vector with
v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i),
and tau in TAU(i).
===================================================================== */
#define dlA(gpu,a_1,a_2) ( dlA[gpu]+(a_2)*(ldda) + (a_1))
#define work_ref(a_1) ( work + (a_1))
#define hwork ( work + (nb)*(m))
#define hwrk_ref(a_1) ( local_work + (a_1))
#define lhwrk ( local_work + (nb)*(m))
float *dwork[4], *panel[4], *local_work;
magma_int_t i, j, k, ldwork, lddwork, old_i, old_ib, rows;
magma_int_t nbmin, nx, ib, nb;
magma_int_t lhwork, lwork;
magma_device_t cdevice;
magma_getdevice(&cdevice);
int panel_gpunum, i_local, n_local[4], la_gpu, displacement;
*info = 0;
if (m < 0) {
*info = -1;
} else if (n < 0) {
*info = -2;
} else if (ldda < max(1,m)) {
*info = -4;
}
if (*info != 0) {
magma_xerbla( __func__, -(*info) );
return *info;
}
k = min(m,n);
if (k == 0)
return *info;
nb = magma_get_sgeqrf_nb(m);
displacement = n * nb;
lwork = (m+n+64) * nb;
lhwork = lwork - (m)*nb;
for(i=0; i<num_gpus; i++){
#ifdef MultiGPUs
magma_setdevice(i);
#endif
if (MAGMA_SUCCESS != magma_smalloc( &(dwork[i]), (n + ldda)*nb )) {
*info = MAGMA_ERR_DEVICE_ALLOC;
return *info;
}
}
/* Set the number of local n for each GPU */
for(i=0; i<num_gpus; i++){
n_local[i] = ((n/nb)/num_gpus)*nb;
if (i < (n/nb)%num_gpus)
n_local[i] += nb;
else if (i == (n/nb)%num_gpus)
n_local[i] += n%nb;
}
if (MAGMA_SUCCESS != magma_smalloc_pinned( &local_work, lwork )) {
*info = -9;
for(i=0; i<num_gpus; i++){
#ifdef MultiGPUs
magma_setdevice(i);
#endif
magma_free( dwork[i] );
}
*info = MAGMA_ERR_HOST_ALLOC;
return *info;
}
cudaStream_t streaml[4][2];
for(i=0; i<num_gpus; i++){
#ifdef MultiGPUs
magma_setdevice(i);
#endif
magma_queue_create( &streaml[i][0] );
magma_queue_create( &streaml[i][1] );
}
nbmin = 2;
nx = nb;
ldwork = m;
lddwork= n;
if (nb >= nbmin && nb < k && nx < k) {
/* Use blocked code initially */
old_i = 0; old_ib = nb;
for (i = 0; i < k-nx; i += nb)
{
/* Set the GPU number that holds the current panel */
panel_gpunum = (i/nb)%num_gpus;
/* Set the local index where the current panel is */
i_local = i/(nb*num_gpus)*nb;
ib = min(k-i, nb);
rows = m -i;
/* Send current panel to the CPU */
#ifdef MultiGPUs
magma_setdevice(panel_gpunum);
#endif
magma_sgetmatrix_async( rows, ib,
dlA(panel_gpunum, i, i_local), ldda,
hwrk_ref(i), ldwork, streaml[panel_gpunum][1] );
if (i>0){
/* Apply H' to A(i:m,i+2*ib:n) from the left; this is the look-ahead
application to the trailing matrix */
la_gpu = panel_gpunum;
/* only the GPU that has next panel is done look-ahead */
#ifdef MultiGPUs
magma_setdevice(la_gpu);
#endif
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaForward, MagmaColumnwise,
m-old_i, n_local[la_gpu]-i_local-old_ib, old_ib,
panel[la_gpu], ldda, dwork[la_gpu], lddwork,
dlA(la_gpu, old_i, i_local+old_ib), ldda,
dwork[la_gpu]+old_ib, lddwork);
la_gpu = ((i-nb)/nb)%num_gpus;
#ifdef MultiGPUs
magma_setdevice(la_gpu);
#endif
magma_ssetmatrix_async( old_ib, old_ib,
hwrk_ref(old_i), ldwork,
panel[la_gpu], ldda, streaml[la_gpu][0] );
}
#ifdef MultiGPUs
magma_setdevice(panel_gpunum);
#endif
magma_queue_sync( streaml[panel_gpunum][1] );
lapackf77_sgeqrf(&rows, &ib, hwrk_ref(i), &ldwork, tau+i, lhwrk, &lhwork, info);
// Form the triangular factor of the block reflector
// H = H(i) H(i+1) . . . H(i+ib-1)
lapackf77_slarft( MagmaForwardStr, MagmaColumnwiseStr,
&rows, &ib,
hwrk_ref(i), &ldwork, tau+i, lhwrk, &ib);
spanel_to_q( MagmaUpper, ib, hwrk_ref(i), ldwork, lhwrk+ib*ib );
// Send the current panel back to the GPUs
// Has to be done with asynchronous copies
for(j=0; j<num_gpus; j++)
{
#ifdef MultiGPUs
magma_setdevice(j);
#endif
if (j == panel_gpunum)
panel[j] = dlA(j, i, i_local);
else
panel[j] = dwork[j]+displacement;
magma_ssetmatrix_async( rows, ib,
hwrk_ref(i), ldwork,
panel[j], ldda, streaml[j][0] );
}
for(j=0; j<num_gpus; j++)
{
#ifdef MultiGPUs
magma_setdevice(j);
#endif
magma_queue_sync( streaml[j][0] );
}
/* Restore the panel */
sq_to_panel( MagmaUpper, ib, hwrk_ref(i), ldwork, lhwrk+ib*ib );
if (i + ib < n)
{
/* Send the T matrix to the GPU.
Has to be done with asynchronous copies */
for(j=0; j<num_gpus; j++)
{
#ifdef MultiGPUs
magma_setdevice(j);
#endif
magma_ssetmatrix_async( ib, ib,
lhwrk, ib,
dwork[j], lddwork, streaml[j][0] );
}
if (i+nb < k-nx)
{
/* Apply H' to A(i:m,i+ib:i+2*ib) from the left;
This is update for the next panel; part of the look-ahead */
la_gpu = (panel_gpunum+1)%num_gpus;
int i_loc = (i+nb)/(nb*num_gpus)*nb;
for(j=0; j<num_gpus; j++){
#ifdef MultiGPUs
magma_setdevice(j);
#endif
//magma_queue_sync( streaml[j][0] );
if (j==la_gpu)
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaForward, MagmaColumnwise,
rows, ib, ib,
panel[j], ldda, dwork[j], lddwork,
dlA(j, i, i_loc), ldda, dwork[j]+ib, lddwork);
else if (j<=panel_gpunum)
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaForward, MagmaColumnwise,
rows, n_local[j]-i_local-ib, ib,
panel[j], ldda, dwork[j], lddwork,
dlA(j, i, i_local+ib), ldda, dwork[j]+ib, lddwork);
else
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaForward, MagmaColumnwise,
rows, n_local[j]-i_local, ib,
panel[j], ldda, dwork[j], lddwork,
dlA(j, i, i_local), ldda, dwork[j]+ib, lddwork);
}
}
else {
/* do the entire update as we exit and there would be no lookahead */
la_gpu = (panel_gpunum+1)%num_gpus;
int i_loc = (i+nb)/(nb*num_gpus)*nb;
#ifdef MultiGPUs
magma_setdevice(la_gpu);
#endif
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaForward, MagmaColumnwise,
rows, n_local[la_gpu]-i_loc, ib,
panel[la_gpu], ldda, dwork[la_gpu], lddwork,
dlA(la_gpu, i, i_loc), ldda, dwork[la_gpu]+ib, lddwork);
#ifdef MultiGPUs
magma_setdevice(panel_gpunum);
#endif
magma_ssetmatrix( ib, ib,
hwrk_ref(i), ldwork,
dlA(panel_gpunum, i, i_local), ldda );
}
old_i = i;
old_ib = ib;
}
}
} else {
i = 0;
}
for(j=0; j<num_gpus; j++){
#ifdef MultiGPUs
magma_setdevice(j);
#endif
magma_free( dwork[j] );
}
/* Use unblocked code to factor the last or only block. */
if (i < k) {
ib = n-i;
rows = m-i;
lhwork = lwork - rows*ib;
panel_gpunum = (panel_gpunum+1)%num_gpus;
int i_loc = (i)/(nb*num_gpus)*nb;
#ifdef MultiGPUs
magma_setdevice(panel_gpunum);
#endif
magma_sgetmatrix( rows, ib,
dlA(panel_gpunum, i, i_loc), ldda,
lhwrk, rows );
lhwork = lwork - rows*ib;
lapackf77_sgeqrf(&rows, &ib, lhwrk, &rows, tau+i, lhwrk+ib*rows, &lhwork, info);
magma_ssetmatrix( rows, ib,
lhwrk, rows,
dlA(panel_gpunum, i, i_loc), ldda );
}
for(i=0; i<num_gpus; i++){
#ifdef MultiGPUs
magma_setdevice(i);
#endif
magma_queue_destroy( streaml[i][0] );
magma_queue_destroy( streaml[i][1] );
}
magma_setdevice(cdevice);
magma_free_pinned( local_work );
return *info;
} /* magma_sgeqrf2_mgpu */
/**
Purpose
-------
SGEQRF computes a QR factorization of a REAL M-by-N matrix A:
A = Q * R. This version does not require work space on the GPU
passed as input. GPU memory is allocated in the routine.
If the current stream is NULL, this version replaces it with user defined
stream to overlap computation with communication.
Arguments
---------
@param[in]
m INTEGER
The number of rows of the matrix A. M >= 0.
@param[in]
n INTEGER
The number of columns of the matrix A. N >= 0.
@param[in,out]
A REAL array, dimension (LDA,N)
On entry, the M-by-N matrix A.
On exit, the elements on and above the diagonal of the array
contain the min(M,N)-by-N upper trapezoidal matrix R (R is
upper triangular if m >= n); the elements below the diagonal,
with the array TAU, represent the orthogonal matrix Q as a
product of min(m,n) elementary reflectors (see Further
Details).
\n
Higher performance is achieved if A is in pinned memory, e.g.
allocated using magma_malloc_pinned.
@param[in]
lda INTEGER
The leading dimension of the array A. LDA >= max(1,M).
@param[out]
tau REAL array, dimension (min(M,N))
The scalar factors of the elementary reflectors (see Further
Details).
@param[out]
work (workspace) REAL array, dimension (MAX(1,LWORK))
On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
\n
Higher performance is achieved if WORK is in pinned memory, e.g.
allocated using magma_malloc_pinned.
@param[in]
lwork INTEGER
The dimension of the array WORK. LWORK >= max( N*NB, 2*NB*NB ),
where NB can be obtained through magma_get_sgeqrf_nb(M).
\n
If LWORK = -1, then a workspace query is assumed; the routine
only calculates the optimal size of the WORK array, returns
this value as the first entry of the WORK array, and no error
message related to LWORK is issued.
@param[out]
info INTEGER
- = 0: successful exit
- < 0: if INFO = -i, the i-th argument had an illegal value
or another error occured, such as memory allocation failed.
Further Details
---------------
The matrix Q is represented as a product of elementary reflectors
Q = H(1) H(2) . . . H(k), where k = min(m,n).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a real scalar, and v is a real vector with
v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i),
and tau in TAU(i).
@ingroup magma_sgeqrf_comp
********************************************************************/
extern "C" magma_int_t
magma_sgeqrf(magma_int_t m, magma_int_t n,
float *A, magma_int_t lda, float *tau,
float *work, magma_int_t lwork,
magma_int_t *info )
{
#define A(i,j) ( A + (i) + (j)*lda )
#define dA(i,j) (dA + (i) + (j)*ldda)
float *dA, *dwork, *dT;
float c_one = MAGMA_S_ONE;
magma_int_t i, k, lddwork, old_i, old_ib;
magma_int_t ib, ldda;
/* Function Body */
*info = 0;
magma_int_t nb = magma_get_sgeqrf_nb(min(m, n));
// need 2*nb*nb to store T and upper triangle of V simultaneously
magma_int_t lwkopt = max(n*nb, 2*nb*nb);
work[0] = MAGMA_S_MAKE( (float)lwkopt, 0 );
int lquery = (lwork == -1);
if (m < 0) {
*info = -1;
} else if (n < 0) {
*info = -2;
} else if (lda < max(1,m)) {
*info = -4;
} else if (lwork < max(1, lwkopt) && ! lquery) {
*info = -7;
}
if (*info != 0) {
magma_xerbla( __func__, -(*info) );
return *info;
}
else if (lquery)
return *info;
k = min(m,n);
if (k == 0) {
work[0] = c_one;
return *info;
}
// largest N for larfb is n-nb (trailing matrix lacks 1st panel)
lddwork = ((n+31)/32)*32 - nb;
ldda = ((m+31)/32)*32;
magma_int_t num_gpus = magma_num_gpus();
if ( num_gpus > 1 ) {
/* call multiple-GPU interface */
return magma_sgeqrf4(num_gpus, m, n, A, lda, tau, work, lwork, info);
}
// allocate space for dA, dwork, and dT
if (MAGMA_SUCCESS != magma_smalloc( &dA, n*ldda + nb*lddwork + nb*nb )) {
/* Switch to the "out-of-core" (out of GPU-memory) version */
return magma_sgeqrf_ooc(m, n, A, lda, tau, work, lwork, info);
}
/* Define user stream if current stream is NULL */
magma_queue_t stream[2], current_stream;
magmablasGetKernelStream(¤t_stream);
magma_queue_create( &stream[0] );
if (current_stream == NULL) {
magma_queue_create( &stream[1] );
magmablasSetKernelStream(stream[1]);
}
else {
stream[1] = current_stream;
}
dwork = dA + n*ldda;
dT = dA + n*ldda + nb*lddwork;
if ( (nb > 1) && (nb < k) ) {
/* Use blocked code initially.
Asynchronously send the matrix to the GPU except the first panel. */
magma_ssetmatrix_async( m, n-nb,
A(0,nb), lda,
dA(0,nb), ldda, stream[0] );
old_i = 0;
old_ib = nb;
for (i = 0; i < k-nb; i += nb) {
ib = min(k-i, nb);
if (i > 0) {
/* download i-th panel */
magma_queue_sync( stream[1] );
magma_sgetmatrix_async( m-i, ib,
dA(i,i), ldda,
A(i,i), lda, stream[0] );
/* Apply H' to A(i:m,i+2*ib:n) from the left */
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaForward, MagmaColumnwise,
m-old_i, n-old_i-2*old_ib, old_ib,
dA(old_i, old_i), ldda, dT, nb,
dA(old_i, old_i+2*old_ib), ldda, dwork, lddwork);
magma_sgetmatrix_async( i, ib,
dA(0,i), ldda,
A(0,i), lda, stream[1] );
magma_queue_sync( stream[0] );
}
magma_int_t rows = m-i;
lapackf77_sgeqrf(&rows, &ib, A(i,i), &lda, tau+i, work, &lwork, info);
/* Form the triangular factor of the block reflector
H = H(i) H(i+1) . . . H(i+ib-1) */
lapackf77_slarft( MagmaForwardStr, MagmaColumnwiseStr,
&rows, &ib, A(i,i), &lda, tau+i, work, &ib);
spanel_to_q(MagmaUpper, ib, A(i,i), lda, work+ib*ib);
/* download the i-th V matrix */
magma_ssetmatrix_async( rows, ib, A(i,i), lda, dA(i,i), ldda, stream[0] );
/* download the T matrix */
magma_queue_sync( stream[1] );
magma_ssetmatrix_async( ib, ib, work, ib, dT, nb, stream[0] );
magma_queue_sync( stream[0] );
if (i + ib < n) {
if (i+ib < k-nb) {
/* Apply H' to A(i:m,i+ib:i+2*ib) from the left (look-ahead) */
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaForward, MagmaColumnwise,
rows, ib, ib,
dA(i, i ), ldda, dT, nb,
dA(i, i+ib), ldda, dwork, lddwork);
sq_to_panel(MagmaUpper, ib, A(i,i), lda, work+ib*ib);
}
else {
/* After last panel, update whole trailing matrix. */
/* Apply H' to A(i:m,i+ib:n) from the left */
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaForward, MagmaColumnwise,
rows, n-i-ib, ib,
dA(i, i ), ldda, dT, nb,
dA(i, i+ib), ldda, dwork, lddwork);
sq_to_panel(MagmaUpper, ib, A(i,i), lda, work+ib*ib);
}
old_i = i;
old_ib = ib;
}
}
} else {
i = 0;
}
/* Use unblocked code to factor the last or only block. */
if (i < k) {
ib = n-i;
if (i != 0) {
magma_sgetmatrix_async( m, ib, dA(0,i), ldda, A(0,i), lda, stream[1] );
magma_queue_sync( stream[1] );
}
magma_int_t rows = m-i;
lapackf77_sgeqrf(&rows, &ib, A(i,i), &lda, tau+i, work, &lwork, info);
}
magma_queue_destroy( stream[0] );
if (current_stream == NULL) {
magma_queue_destroy( stream[1] );
magmablasSetKernelStream(NULL);
}
magma_free( dA );
return *info;
} /* magma_sgeqrf */
extern "C" magma_int_t
magma_sgeqrf_msub(
magma_int_t num_subs, magma_int_t num_gpus,
magma_int_t m, magma_int_t n,
magmaFloat_ptr *dlA, magma_int_t ldda,
float *tau,
magma_queue_t *queues,
magma_int_t *info)
{
/* -- clMAGMA (version 1.3.0) --
Univ. of Tennessee, Knoxville
Univ. of California, Berkeley
Univ. of Colorado, Denver
@date November 2014
Purpose
=======
SGEQRF2_MGPU computes a QR factorization of a real M-by-N matrix A:
A = Q * R. This is a GPU interface of the routine.
Arguments
=========
M (input) INTEGER
The number of rows of the matrix A. M >= 0.
N (input) INTEGER
The number of columns of the matrix A. N >= 0.
dA (input/output) REAL array on the GPU, dimension (LDDA,N)
On entry, the M-by-N matrix dA.
On exit, the elements on and above the diagonal of the array
contain the min(M,N)-by-N upper trapezoidal matrix R (R is
upper triangular if m >= n); the elements below the diagonal,
with the array TAU, represent the orthogonal matrix Q as a
product of min(m,n) elementary reflectors (see Further
Details).
LDDA (input) INTEGER
The leading dimension of the array dA. LDDA >= max(1,M).
To benefit from coalescent memory accesses LDDA must be
divisible by 16.
TAU (output) REAL array, dimension (min(M,N))
The scalar factors of the elementary reflectors (see Further
Details).
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
or another error occured, such as memory allocation failed.
Further Details
===============
The matrix Q is represented as a product of elementary reflectors
Q = H(1) H(2) . . . H(k), where k = min(m,n).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a real scalar, and v is a real vector with
v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i),
and tau in TAU(i).
===================================================================== */
#define dlA(gpu,a_1,a_2) dlA[gpu], ((a_2)*(ldda) + (a_1))
#define dlA_offset(a_1, a_2) ((a_2)*(ldda) + (a_1))
#define work_ref(a_1) ( work + (a_1))
#define hwork ( work + (nb)*(m))
#define hwrk(a_1) ( local_work + (a_1))
#define lhwrk ( local_work + (nb)*(m))
magmaFloat_ptr dwork[MagmaMaxGPUs], panel[MagmaMaxGPUs];
size_t panel_offset[MagmaMaxGPUs];
float *local_work = NULL;
magma_int_t i, j, k, ldwork, lddwork, old_i, old_ib, rows;
magma_int_t nbmin, nx, ib, nb;
magma_int_t lhwork, lwork;
int panel_id = -1, i_local, n_local[MagmaMaxGPUs * MagmaMaxSubs], la_id, displacement,
tot_subs = num_gpus * num_subs;
*info = 0;
if (m < 0) {
*info = -1;
} else if (n < 0) {
*info = -2;
} else if (ldda < max(1,m)) {
*info = -4;
}
if (*info != 0) {
magma_xerbla( __func__, -(*info) );
return *info;
}
k = min(m,n);
if (k == 0)
return *info;
nb = magma_get_sgeqrf_nb(m);
displacement = n * nb;
lwork = (m+n+64) * nb;
lhwork = lwork - (m)*nb;
for (i=0; i<num_gpus; i++) {
if (MAGMA_SUCCESS != magma_smalloc( &(dwork[i]), (n + ldda)*nb )) {
*info = MAGMA_ERR_DEVICE_ALLOC;
return *info;
}
}
/* Set the number of local n for each GPU */
for (i=0; i<tot_subs; i++) {
n_local[i] = ((n/nb)/tot_subs)*nb;
if (i < (n/nb)%tot_subs)
n_local[i] += nb;
else if (i == (n/nb)%tot_subs)
n_local[i] += n%nb;
}
#ifdef USE_PINNED_CLMEMORY
cl_mem buffer = clCreateBuffer(gContext, CL_MEM_READ_WRITE | CL_MEM_ALLOC_HOST_PTR, sizeof(float)*lwork, NULL, NULL);
for (j=0; j<num_gpus; j++) {
local_work = (float*)clEnqueueMapBuffer(queues[2*j], buffer, CL_TRUE, CL_MAP_READ | CL_MAP_WRITE, 0,
sizeof(float)*lwork, 0, NULL, NULL, NULL);
}
#else
if (MAGMA_SUCCESS != magma_smalloc_cpu( (&local_work), lwork )) {
*info = -9;
for (i=0; i<num_gpus; i++) {
magma_free( dwork[i] );
}
*info = MAGMA_ERR_HOST_ALLOC;
return *info;
}
#endif
nbmin = 2;
nx = nb;
ldwork = m;
lddwork= n;
if (nb >= nbmin && nb < k && nx < k) {
/* Use blocked code initially */
old_i = 0; old_ib = nb;
for (i = 0; i < k-nx; i += nb) {
/* Set the GPU number that holds the current panel */
panel_id = (i/nb)%tot_subs;
/* Set the local index where the current panel is */
i_local = i/(nb*tot_subs)*nb;
ib = min(k-i, nb);
rows = m -i;
/* Send current panel to the CPU */
magma_queue_sync(queues[2*(panel_id%num_gpus)]);
magma_sgetmatrix_async( rows, ib,
dlA(panel_id, i, i_local), ldda,
hwrk(i), ldwork,
queues[2*(panel_id%num_gpus)+1], NULL );
if (i > 0) {
/* Apply H' to A(i:m,i+2*ib:n) from the left; this is the look-ahead
application to the trailing matrix */
la_id = panel_id;
/* only the GPU that has next panel is done look-ahead */
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
m-old_i, n_local[la_id]-i_local-old_ib, old_ib,
panel[la_id%num_gpus], panel_offset[la_id%num_gpus], ldda,
dwork[la_id%num_gpus], 0, lddwork,
dlA(la_id, old_i, i_local+old_ib), ldda,
dwork[la_id%num_gpus], old_ib, lddwork,
queues[2*(la_id%num_gpus)]);
la_id = ((i-nb)/nb)%tot_subs;
magma_ssetmatrix_async( old_ib, old_ib,
hwrk(old_i), ldwork,
panel[la_id%num_gpus], panel_offset[la_id%num_gpus], ldda,
queues[2*(la_id%num_gpus)], NULL );
}
magma_queue_sync( queues[2*(panel_id%num_gpus)+1] );
lapackf77_sgeqrf(&rows, &ib, hwrk(i), &ldwork, tau+i, lhwrk, &lhwork, info);
// Form the triangular factor of the block reflector
// H = H(i) H(i+1) . . . H(i+ib-1)
lapackf77_slarft( MagmaForwardStr, MagmaColumnwiseStr,
&rows, &ib,
hwrk(i), &ldwork, tau+i, lhwrk, &ib);
spanel_to_q( MagmaUpper, ib, hwrk(i), ldwork, lhwrk+ib*ib );
// Send the current panel back to the GPUs
// Has to be done with asynchronous copies
for (j=0; j<num_gpus; j++) {
if (j == panel_id%num_gpus){
panel[j] = dlA(panel_id, i, i_local);
panel_offset[j] = dlA_offset(i, i_local);
} else {
panel[j] = dwork[j];
panel_offset[j] = displacement;
}
magma_queue_sync( queues[2*j] );
magma_ssetmatrix_async( rows, ib,
hwrk(i), ldwork,
panel[j], panel_offset[j], ldda,
queues[2*j+1], NULL );
/* Send the T matrix to the GPU.
Has to be done with asynchronous copies */
magma_ssetmatrix_async( ib, ib, lhwrk, ib,
dwork[j], 0, lddwork,
queues[2*j+1], NULL );
}
for(j=0; j<num_gpus; j++) {
magma_queue_sync( queues[2*j+1] );
}
if (i + ib < n) {
if (i+nb < k-nx) {
/* Apply H' to A(i:m,i+ib:i+2*ib) from the left;
This is update for the next panel; part of the look-ahead */
la_id = (panel_id+1)%tot_subs;
int i_loc = (i+nb)/(nb*tot_subs)*nb;
for (j=0; j<tot_subs; j++) {
if (j == la_id)
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
rows, ib, ib,
panel[j%num_gpus], panel_offset[j%num_gpus], ldda,
dwork[j%num_gpus], 0, lddwork,
dlA(j, i, i_loc), ldda,
dwork[j%num_gpus], ib, lddwork,
queues[2*(j%num_gpus)]);
else if (j <= panel_id)
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
rows, n_local[j]-i_local-ib, ib,
panel[j%num_gpus], panel_offset[j%num_gpus], ldda,
dwork[j%num_gpus], 0, lddwork,
dlA(j, i, i_local+ib), ldda,
dwork[j%num_gpus], ib, lddwork,
queues[2*(j%num_gpus)]);
else
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
rows, n_local[j]-i_local, ib,
panel[j%num_gpus], panel_offset[j%num_gpus], ldda,
dwork[j%num_gpus], 0, lddwork,
dlA(j, i, i_local), ldda,
dwork[j%num_gpus], ib, lddwork,
queues[2*(j%num_gpus)]);
}
/* Restore the panel */
sq_to_panel( MagmaUpper, ib, hwrk(i), ldwork, lhwrk+ib*ib );
} else {
/* do the entire update as we exit and there would be no lookahead */
la_id = (panel_id+1)%tot_subs;
int i_loc = (i+nb)/(nb*tot_subs)*nb;
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
rows, n_local[la_id]-i_loc, ib,
panel[la_id%num_gpus], panel_offset[la_id%num_gpus], ldda,
dwork[la_id%num_gpus], 0, lddwork,
dlA(la_id, i, i_loc), ldda,
dwork[la_id%num_gpus], ib, lddwork,
queues[2*(la_id%num_gpus)]);
/* Restore the panel */
sq_to_panel( MagmaUpper, ib, hwrk(i), ldwork, lhwrk+ib*ib );
magma_ssetmatrix( ib, ib,
hwrk(i), ldwork,
dlA(panel_id, i, i_local), ldda,
queues[2*(panel_id%num_gpus)]);
}
old_i = i;
old_ib = ib;
}
}
} else {
i = 0;
}
for (j=0; j<num_gpus; j++) {
magma_free( dwork[j] );
}
/* Use unblocked code to factor the last or only block. */
if (i < k) {
ib = n-i;
rows = m-i;
lhwork = lwork - rows*ib;
panel_id = (panel_id+1)%tot_subs;
int i_loc = (i)/(nb*tot_subs)*nb;
magma_sgetmatrix( rows, ib,
dlA(panel_id, i, i_loc), ldda,
lhwrk, rows,
queues[2*(panel_id%num_gpus)]);
lhwork = lwork - rows*ib;
lapackf77_sgeqrf(&rows, &ib, lhwrk, &rows, tau+i, lhwrk+ib*rows, &lhwork, info);
magma_ssetmatrix( rows, ib,
lhwrk, rows,
dlA(panel_id, i, i_loc), ldda,
queues[2*(panel_id%num_gpus)]);
}
#ifdef USE_PINNED_CLMEMORY
#else
magma_free_cpu( local_work );
#endif
return *info;
} /* magma_sgeqrf_msub */
/**
Purpose
-------
SGEQRF computes a QR factorization of a real M-by-N matrix A:
A = Q * R.
This version has LAPACK-complaint arguments.
If the current stream is NULL, this version replaces it with a new
stream to overlap computation with communication.
Other versions (magma_sgeqrf_gpu and magma_sgeqrf3_gpu) store the
intermediate T matrices.
Arguments
---------
@param[in]
m INTEGER
The number of rows of the matrix A. M >= 0.
@param[in]
n INTEGER
The number of columns of the matrix A. N >= 0.
@param[in,out]
dA REAL array on the GPU, dimension (LDDA,N)
On entry, the M-by-N matrix A.
On exit, the elements on and above the diagonal of the array
contain the min(M,N)-by-N upper trapezoidal matrix R (R is
upper triangular if m >= n); the elements below the diagonal,
with the array TAU, represent the orthogonal matrix Q as a
product of min(m,n) elementary reflectors (see Further
Details).
@param[in]
ldda INTEGER
The leading dimension of the array dA. LDDA >= max(1,M).
To benefit from coalescent memory accesses LDDA must be
divisible by 16.
@param[out]
tau REAL array, dimension (min(M,N))
The scalar factors of the elementary reflectors (see Further
Details).
@param[out]
info INTEGER
- = 0: successful exit
- < 0: if INFO = -i, the i-th argument had an illegal value
or another error occured, such as memory allocation failed.
Further Details
---------------
The matrix Q is represented as a product of elementary reflectors
Q = H(1) H(2) . . . H(k), where k = min(m,n).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a real scalar, and v is a real vector with
v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i),
and tau in TAU(i).
@ingroup magma_sgeqrf_comp
********************************************************************/
extern "C" magma_int_t
magma_sgeqrf2_gpu(
magma_int_t m, magma_int_t n,
magmaFloat_ptr dA, magma_int_t ldda,
float *tau,
magma_int_t *info )
{
#define dA(a_1,a_2) ( dA+(a_2)*(ldda) + (a_1))
#define work_ref(a_1) ( work + (a_1))
#define hwork ( work + (nb)*(m))
magmaFloat_ptr dwork;
float *work;
magma_int_t i, k, ldwork, lddwork, old_i, old_ib, rows;
magma_int_t nbmin, nx, ib, nb;
magma_int_t lhwork, lwork;
/* Function Body */
*info = 0;
if (m < 0) {
*info = -1;
} else if (n < 0) {
*info = -2;
} else if (ldda < max(1,m)) {
*info = -4;
}
if (*info != 0) {
magma_xerbla( __func__, -(*info) );
return *info;
}
k = min(m,n);
if (k == 0)
return *info;
nb = magma_get_sgeqrf_nb(m);
lwork = (m+n) * nb;
lhwork = lwork - (m)*nb;
if (MAGMA_SUCCESS != magma_smalloc( &dwork, n*nb )) {
*info = MAGMA_ERR_DEVICE_ALLOC;
return *info;
}
if (MAGMA_SUCCESS != magma_smalloc_pinned( &work, lwork )) {
magma_free( dwork );
*info = MAGMA_ERR_HOST_ALLOC;
return *info;
}
/* Define user stream if current stream is NULL */
magma_queue_t stream[2];
magma_queue_t orig_stream;
magmablasGetKernelStream( &orig_stream );
magma_queue_create( &stream[0] );
if (orig_stream == NULL) {
magma_queue_create( &stream[1] );
magmablasSetKernelStream(stream[1]);
}
else {
stream[1] = orig_stream;
}
nbmin = 2;
nx = nb;
ldwork = m;
lddwork= n;
if (nb >= nbmin && nb < k && nx < k) {
/* Use blocked code initially */
old_i = 0; old_ib = nb;
for (i = 0; i < k-nx; i += nb) {
ib = min(k-i, nb);
rows = m -i;
/* download i-th panel */
magma_queue_sync( stream[1] );
magma_sgetmatrix_async( rows, ib,
dA(i,i), ldda,
work_ref(i), ldwork, stream[0] );
if (i > 0) {
/* Apply H' to A(i:m,i+2*ib:n) from the left */
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
m-old_i, n-old_i-2*old_ib, old_ib,
dA(old_i, old_i ), ldda, dwork, lddwork,
dA(old_i, old_i+2*old_ib), ldda, dwork+old_ib, lddwork);
magma_ssetmatrix_async( old_ib, old_ib,
work_ref(old_i), ldwork,
dA(old_i, old_i), ldda, stream[1] );
}
magma_queue_sync( stream[0] );
lapackf77_sgeqrf(&rows, &ib, work_ref(i), &ldwork, tau+i, hwork, &lhwork, info);
/* Form the triangular factor of the block reflector
H = H(i) H(i+1) . . . H(i+ib-1) */
lapackf77_slarft( MagmaForwardStr, MagmaColumnwiseStr,
&rows, &ib,
work_ref(i), &ldwork, tau+i, hwork, &ib);
spanel_to_q( MagmaUpper, ib, work_ref(i), ldwork, hwork+ib*ib );
/* download the i-th V matrix */
magma_ssetmatrix_async( rows, ib, work_ref(i), ldwork, dA(i,i), ldda, stream[0] );
/* download the T matrix */
magma_queue_sync( stream[1] );
magma_ssetmatrix_async( ib, ib, hwork, ib, dwork, lddwork, stream[0] );
magma_queue_sync( stream[0] );
if (i + ib < n) {
if (i+nb < k-nx) {
/* Apply H' to A(i:m,i+ib:i+2*ib) from the left */
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
rows, ib, ib,
dA(i, i ), ldda, dwork, lddwork,
dA(i, i+ib), ldda, dwork+ib, lddwork);
sq_to_panel( MagmaUpper, ib, work_ref(i), ldwork, hwork+ib*ib );
}
else {
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
rows, n-i-ib, ib,
dA(i, i ), ldda, dwork, lddwork,
dA(i, i+ib), ldda, dwork+ib, lddwork);
sq_to_panel( MagmaUpper, ib, work_ref(i), ldwork, hwork+ib*ib );
magma_ssetmatrix_async( ib, ib,
work_ref(i), ldwork,
dA(i,i), ldda, stream[1] );
}
old_i = i;
old_ib = ib;
}
}
} else {
i = 0;
}
magma_free( dwork );
/* Use unblocked code to factor the last or only block. */
if (i < k) {
ib = n-i;
rows = m-i;
magma_sgetmatrix_async( rows, ib, dA(i, i), ldda, work, rows, stream[1] );
magma_queue_sync( stream[1] );
lhwork = lwork - rows*ib;
lapackf77_sgeqrf(&rows, &ib, work, &rows, tau+i, work+ib*rows, &lhwork, info);
magma_ssetmatrix_async( rows, ib, work, rows, dA(i, i), ldda, stream[1] );
}
magma_free_pinned( work );
magma_queue_destroy( stream[0] );
if (orig_stream == NULL) {
magma_queue_destroy( stream[1] );
}
magmablasSetKernelStream( orig_stream );
return *info;
} /* magma_sgeqrf2_gpu */
extern "C" magma_int_t
magma_sgeqlf(magma_int_t m, magma_int_t n,
float *a, magma_int_t lda, float *tau,
float *work, magma_int_t lwork, magma_int_t *info)
{
/* -- MAGMA (version 1.3.0) --
Univ. of Tennessee, Knoxville
Univ. of California, Berkeley
Univ. of Colorado, Denver
November 2012
Purpose
=======
SGEQLF computes a QL factorization of a REAL M-by-N matrix A:
A = Q * L.
Arguments
=========
M (input) INTEGER
The number of rows of the matrix A. M >= 0.
N (input) INTEGER
The number of columns of the matrix A. N >= 0.
A (input/output) REAL array, dimension (LDA,N)
On entry, the M-by-N matrix A.
On exit, if m >= n, the lower triangle of the subarray
A(m-n+1:m,1:n) contains the N-by-N lower triangular matrix L;
if m <= n, the elements on and below the (n-m)-th
superdiagonal contain the M-by-N lower trapezoidal matrix L;
the remaining elements, with the array TAU, represent the
orthogonal matrix Q as a product of elementary reflectors
(see Further Details).
Higher performance is achieved if A is in pinned memory, e.g.
allocated using magma_malloc_pinned.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,M).
TAU (output) REAL array, dimension (min(M,N))
The scalar factors of the elementary reflectors (see Further
Details).
WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
Higher performance is achieved if WORK is in pinned memory, e.g.
allocated using magma_malloc_pinned.
LWORK (input) INTEGER
The dimension of the array WORK. LWORK >= max(1,N).
For optimum performance LWORK >= N*NB, where NB can be obtained
through magma_get_sgeqlf_nb(M).
If LWORK = -1, then a workspace query is assumed; the routine
only calculates the optimal size of the WORK array, returns
this value as the first entry of the WORK array, and no error
message related to LWORK is issued by XERBLA.
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
or another error occured, such as memory allocation failed.
Further Details
===============
The matrix Q is represented as a product of elementary reflectors
Q = H(k) . . . H(2) H(1), where k = min(m,n).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a real scalar, and v is a real vector with
v(m-k+i+1:m) = 0 and v(m-k+i) = 1; v(1:m-k+i-1) is stored on exit in
A(1:m-k+i-1,n-k+i), and tau in TAU(i).
===================================================================== */
#define a_ref(a_1,a_2) ( a+(a_2)*(lda) + (a_1))
#define da_ref(a_1,a_2) (da+(a_2)*ldda + (a_1))
float *da, *dwork;
float c_one = MAGMA_S_ONE;
magma_int_t i, k, lddwork, old_i, old_ib, nb;
magma_int_t rows, cols;
magma_int_t ib, ki, kk, mu, nu, iinfo, ldda;
int lquery;
nb = magma_get_sgeqlf_nb(m);
*info = 0;
lquery = (lwork == -1);
if (m < 0) {
*info = -1;
} else if (n < 0) {
*info = -2;
} else if (lda < max(1,m)) {
*info = -4;
}
if (*info == 0) {
k = min(m,n);
if (k == 0)
work[0] = c_one;
else {
work[0] = MAGMA_S_MAKE( n*nb, 0 );
}
if (lwork < max(1,n) && ! lquery)
*info = -7;
}
if (*info != 0) {
magma_xerbla( __func__, -(*info) );
return *info;
}
else if (lquery)
return *info;
/* Quick return if possible */
if (k == 0)
return *info;
lddwork = ((n+31)/32)*32;
ldda = ((m+31)/32)*32;
if (MAGMA_SUCCESS != magma_smalloc( &da, (n)*ldda + nb*lddwork )) {
*info = MAGMA_ERR_DEVICE_ALLOC;
return *info;
}
dwork = da + ldda*(n);
cudaStream_t stream[2];
magma_queue_create( &stream[0] );
magma_queue_create( &stream[1] );
if ( (nb > 1) && (nb < k) ) {
/* Use blocked code initially.
The last kk columns are handled by the block method.
First, copy the matrix on the GPU except the last kk columns */
magma_ssetmatrix_async( (m), (n-nb),
a_ref(0, 0), lda,
da_ref(0, 0), ldda, stream[0] );
ki = ((k - nb - 1) / nb) * nb;
kk = min(k, ki + nb);
for (i = k - kk + ki; i >= k -kk; i -= nb) {
ib = min(k-i,nb);
if (i< k - kk + ki){
/* 1. Copy asynchronously the current panel to the CPU.
2. Copy asynchronously the submatrix below the panel
to the CPU) */
rows = m - k + i + ib;
magma_sgetmatrix_async( rows, ib,
da_ref(0, n-k+i), ldda,
a_ref(0, n-k+i), lda, stream[1] );
magma_sgetmatrix_async( (m-rows), ib,
da_ref(rows, n-k+i), ldda,
a_ref(rows, n-k+i), lda, stream[0] );
/* Apply H' to A(1:m-k+i+ib-1,1:n-k+i-1) from the left in
two steps - implementing the lookahead techniques.
This is the main update from the lookahead techniques. */
rows = m - k + old_i + old_ib;
cols = n - k + old_i - old_ib;
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaBackward, MagmaColumnwise,
rows, cols, old_ib,
da_ref(0, cols+old_ib), ldda, dwork, lddwork,
da_ref(0, 0 ), ldda, dwork+old_ib, lddwork);
}
magma_queue_sync( stream[1] );
/* Compute the QL factorization of the current block
A(1:m-k+i+ib-1,n-k+i:n-k+i+ib-1) */
rows = m - k + i + ib;
cols = n - k + i;
lapackf77_sgeqlf(&rows,&ib, a_ref(0,cols), &lda, tau+i, work, &lwork, &iinfo);
if (cols > 0) {
/* Form the triangular factor of the block reflector
H = H(i+ib-1) . . . H(i+1) H(i) */
lapackf77_slarft( MagmaBackwardStr, MagmaColumnwiseStr,
&rows, &ib,
a_ref(0, cols), &lda, tau + i, work, &ib);
spanel_to_q( MagmaLower, ib, a_ref(rows-ib,cols), lda, work+ib*ib);
magma_ssetmatrix( rows, ib,
a_ref(0,cols), lda,
da_ref(0,cols), ldda );
sq_to_panel( MagmaLower, ib, a_ref(rows-ib,cols), lda, work+ib*ib);
// Send the triangular part on the GPU
magma_ssetmatrix( ib, ib, work, ib, dwork, lddwork );
/* Apply H' to A(1:m-k+i+ib-1,1:n-k+i-1) from the left in
two steps - implementing the lookahead techniques.
This is the update of first ib columns. */
if (i-ib >= k -kk)
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaBackward, MagmaColumnwise,
rows, ib, ib,
da_ref(0, cols), ldda, dwork, lddwork,
da_ref(0,cols-ib), ldda, dwork+ib, lddwork);
else{
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaBackward, MagmaColumnwise,
rows, cols, ib,
da_ref(0, cols), ldda, dwork, lddwork,
da_ref(0, 0 ), ldda, dwork+ib, lddwork);
}
old_i = i;
old_ib = ib;
}
}
mu = m - k + i + nb;
nu = n - k + i + nb;
magma_sgetmatrix( m, nu, da_ref(0,0), ldda, a_ref(0,0), lda );
} else {
mu = m;
nu = n;
}
/* Use unblocked code to factor the last or only block */
if (mu > 0 && nu > 0)
lapackf77_sgeqlf(&mu, &nu, a_ref(0,0), &lda, tau, work, &lwork, &iinfo);
magma_queue_destroy( stream[0] );
magma_queue_destroy( stream[1] );
magma_free( da );
return *info;
} /* magma_sgeqlf */
extern "C" magma_int_t
magma_sormqr(magma_side_t side, magma_trans_t trans,
magma_int_t m, magma_int_t n, magma_int_t k,
float *a, magma_int_t lda,
float *tau,
float *c, magma_int_t ldc,
float *work, magma_int_t lwork,
magma_int_t *info, magma_queue_t queue)
{
/* -- MAGMA (version 1.0.0) --
Univ. of Tennessee, Knoxville
Univ. of California, Berkeley
Univ. of Colorado, Denver
September 2012
Purpose
=======
SORMQR overwrites the general real M-by-N matrix C with
SIDE = 'L' SIDE = 'R'
TRANS = 'N': Q * C C * Q
TRANS = 'T': Q**T * C C * Q**T
where Q is a real orthogonal matrix defined as the product of k
elementary reflectors
Q = H(1) H(2) . . . H(k)
as returned by SGEQRF. Q is of order M if SIDE = 'L' and of order N
if SIDE = 'R'.
Arguments
=========
SIDE (input) CHARACTER*1
= 'L': apply Q or Q**T from the Left;
= 'R': apply Q or Q**T from the Right.
TRANS (input) CHARACTER*1
= 'N': No transpose, apply Q;
= 'T': Transpose, apply Q**T.
M (input) INTEGER
The number of rows of the matrix C. M >= 0.
N (input) INTEGER
The number of columns of the matrix C. N >= 0.
K (input) INTEGER
The number of elementary reflectors whose product defines
the matrix Q.
If SIDE = 'L', M >= K >= 0;
if SIDE = 'R', N >= K >= 0.
A (input) REAL array, dimension (LDA,K)
The i-th column must contain the vector which defines the
elementary reflector H(i), for i = 1,2,...,k, as returned by
SGEQRF in the first k columns of its array argument A.
A is modified by the routine but restored on exit.
LDA (input) INTEGER
The leading dimension of the array A.
If SIDE = 'L', LDA >= max(1,M);
if SIDE = 'R', LDA >= max(1,N).
TAU (input) REAL array, dimension (K)
TAU(i) must contain the scalar factor of the elementary
reflector H(i), as returned by SGEQRF.
C (input/output) REAL array, dimension (LDC,N)
On entry, the M-by-N matrix C.
On exit, C is overwritten by Q*C or Q**T * C or C * Q**T or C*Q.
LDC (input) INTEGER
The leading dimension of the array C. LDC >= max(1,M).
WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
On exit, if INFO = 0, WORK(0) returns the optimal LWORK.
LWORK (input) INTEGER
The dimension of the array WORK.
If SIDE = 'L', LWORK >= max(1,N);
if SIDE = 'R', LWORK >= max(1,M).
For optimum performance LWORK >= N*NB if SIDE = 'L', and
LWORK >= M*NB if SIDE = 'R', where NB is the optimal
blocksize.
If LWORK = -1, then a workspace query is assumed; the routine
only calculates the optimal size of the WORK array, returns
this value as the first entry of the WORK array, and no error
message related to LWORK is issued by XERBLA.
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
===================================================================== */
float c_one = MAGMA_S_ONE;
magma_side_t side_ = side;
magma_trans_t trans_ = trans;
/* Allocate work space on the GPU */
magmaFloat_ptr dwork, dc;
magma_malloc( &dc, (m)*(n)*sizeof(float) );
magma_malloc( &dwork, (m + n + 64)*64*sizeof(float) );
/* Copy matrix C from the CPU to the GPU */
magma_ssetmatrix( m, n, c, 0, ldc, dc, 0, m, queue );
//dc -= (1 + m);
size_t dc_offset = -(1+m);
magma_int_t a_offset, c_offset, i__4, lddwork;
magma_int_t i__;
float t[2*4160] /* was [65][64] */;
magma_int_t i1, i2, i3, ib, ic, jc, nb, mi, ni, nq, nw;
int left, notran, lquery;
magma_int_t iinfo, lwkopt;
a_offset = 1 + lda;
a -= a_offset;
--tau;
c_offset = 1 + ldc;
c -= c_offset;
*info = 0;
left = lapackf77_lsame(lapack_const(side_), "L");
notran = lapackf77_lsame(lapack_const(trans_), "N");
lquery = (lwork == -1);
/* NQ is the order of Q and NW is the minimum dimension of WORK */
if (left) {
nq = m;
nw = n;
} else {
nq = n;
nw = m;
}
if (! left && ! lapackf77_lsame(lapack_const(side_), "R")) {
*info = -1;
} else if (! notran && ! lapackf77_lsame(lapack_const(trans_), "T")) {
*info = -2;
} else if (m < 0) {
*info = -3;
} else if (n < 0) {
*info = -4;
} else if (k < 0 || k > nq) {
*info = -5;
} else if (lda < max(1,nq)) {
*info = -7;
} else if (ldc < max(1,m)) {
*info = -10;
} else if (lwork < max(1,nw) && ! lquery) {
*info = -12;
}
if (*info == 0)
{
/* Determine the block size. NB may be at most NBMAX, where NBMAX
is used to define the local array T. */
nb = 64;
lwkopt = max(1,nw) * nb;
// ACD
// MAGMA_S_SET2REAL( work[0], lwkopt );
MAGMA_S_SET2REAL( work[0], (float) lwkopt );
}
if (*info != 0) {
magma_xerbla( __func__, -(*info) );
return *info;
}
else if (lquery) {
return *info;
}
/* Quick return if possible */
if (m == 0 || n == 0 || k == 0) {
work[0] = c_one;
return *info;
}
if (nb >= k)
{
/* Use CPU code */
lapackf77_sormqr(lapack_const(side_), lapack_const(trans_), &m, &n, &k, &a[a_offset], &lda, &tau[1],
&c[c_offset], &ldc, work, &lwork, &iinfo);
}
else
{
/* Use hybrid CPU-GPU code */
if ( ( left && (! notran) ) || ( (! left) && notran ) ) {
i1 = 1;
i2 = k;
i3 = nb;
} else {
i1 = (k - 1) / nb * nb + 1;
i2 = 1;
i3 = -nb;
}
if (left) {
ni = n;
jc = 1;
} else {
mi = m;
ic = 1;
}
for (i__ = i1; i3 < 0 ? i__ >= i2 : i__ <= i2; i__ += i3)
{
ib = min(nb, k - i__ + 1);
/* Form the triangular factor of the block reflector
H = H(i) H(i+1) . . . H(i+ib-1) */
i__4 = nq - i__ + 1;
lapackf77_slarft("F", "C", &i__4, &ib, &a[i__ + i__ * lda], &lda,
&tau[i__], t, &ib);
/* 1) Put 0s in the upper triangular part of A;
2) copy the panel from A to the GPU, and
3) restore A */
spanel_to_q(MagmaUpper, ib, &a[i__ + i__ * lda], lda, t+ib*ib);
magma_ssetmatrix( i__4, ib, &a[i__ + i__ * lda], 0, lda, dwork, 0, i__4, queue );
sq_to_panel(MagmaUpper, ib, &a[i__ + i__ * lda], lda, t+ib*ib);
if (left)
{
/* H or H' is applied to C(i:m,1:n) */
mi = m - i__ + 1;
ic = i__;
}
else
{
/* H or H' is applied to C(1:m,i:n) */
ni = n - i__ + 1;
jc = i__;
}
if (left)
lddwork = ni;
else
lddwork = mi;
/* Apply H or H'; First copy T to the GPU */
magma_ssetmatrix( ib, ib, t, 0, ib, dwork, i__4*ib, ib, queue );
magma_slarfb_gpu( side, trans, MagmaForward, MagmaColumnwise,
mi, ni, ib,
dwork, 0, i__4, dwork, i__4*ib, ib,
dc, dc_offset+(ic + jc * m), m,
dwork, (i__4*ib + ib*ib), lddwork, queue);
}
magma_sgetmatrix( m, n, dc, dc_offset+(1+m), m, &c[c_offset], 0, ldc, queue );
}
// ACD
// MAGMA_S_SET2REAL( work[0], lwkopt );
MAGMA_S_SET2REAL( work[0], (float) lwkopt );
//dc += (1 + m);
magma_free( dc );
magma_free( dwork );
return *info;
} /* magma_sormqr */
/**
Purpose
-------
SORMQR overwrites the general real M-by-N matrix C with
@verbatim
SIDE = MagmaLeft SIDE = MagmaRight
TRANS = MagmaNoTrans: Q * C C * Q
TRANS = MagmaTrans: Q**H * C C * Q**H
@endverbatim
where Q is a real unitary matrix defined as the product of k
elementary reflectors
Q = H(1) H(2) . . . H(k)
as returned by SGEQRF. Q is of order M if SIDE = MagmaLeft and of order N
if SIDE = MagmaRight.
Arguments
---------
@param[in]
side magma_side_t
- = MagmaLeft: apply Q or Q**H from the Left;
- = MagmaRight: apply Q or Q**H from the Right.
@param[in]
trans magma_trans_t
- = MagmaNoTrans: No transpose, apply Q;
- = MagmaTrans: Conjugate transpose, apply Q**H.
@param[in]
m INTEGER
The number of rows of the matrix C. M >= 0.
@param[in]
n INTEGER
The number of columns of the matrix C. N >= 0.
@param[in]
k INTEGER
The number of elementary reflectors whose product defines
the matrix Q.
If SIDE = MagmaLeft, M >= K >= 0;
if SIDE = MagmaRight, N >= K >= 0.
@param[in]
A REAL array, dimension (LDA,K)
The i-th column must contain the vector which defines the
elementary reflector H(i), for i = 1,2,...,k, as returned by
SGEQRF in the first k columns of its array argument A.
A is modified by the routine but restored on exit.
@param[in]
lda INTEGER
The leading dimension of the array A.
If SIDE = MagmaLeft, LDA >= max(1,M);
if SIDE = MagmaRight, LDA >= max(1,N).
@param[in]
tau REAL array, dimension (K)
TAU(i) must contain the scalar factor of the elementary
reflector H(i), as returned by SGEQRF.
@param[in,out]
C REAL array, dimension (LDC,N)
On entry, the M-by-N matrix C.
On exit, C is overwritten by Q*C or Q**H * C or C * Q**H or C*Q.
@param[in]
ldc INTEGER
The leading dimension of the array C. LDC >= max(1,M).
@param[out]
work (workspace) REAL array, dimension (MAX(1,LWORK))
On exit, if INFO = 0, WORK[0] returns the optimal LWORK.
@param[in]
lwork INTEGER
The dimension of the array WORK.
If SIDE = MagmaLeft, LWORK >= max(1,N);
if SIDE = MagmaRight, LWORK >= max(1,M).
For optimum performance
if SIDE = MagmaLeft, LWORK >= N*NB;
if SIDE = MagmaRight, LWORK >= M*NB,
where NB is the optimal blocksize.
\n
If LWORK = -1, then a workspace query is assumed; the routine
only calculates the optimal size of the WORK array, returns
this value as the first entry of the WORK array, and no error
message related to LWORK is issued by XERBLA.
@param[out]
info INTEGER
- = 0: successful exit
- < 0: if INFO = -i, the i-th argument had an illegal value
@ingroup magma_sgeqrf_comp
********************************************************************/
extern "C" magma_int_t
magma_sormqr(
magma_side_t side, magma_trans_t trans,
magma_int_t m, magma_int_t n, magma_int_t k,
float *A, magma_int_t lda,
float *tau,
float *C, magma_int_t ldc,
float *work, magma_int_t lwork,
magma_int_t *info)
{
#define A(i_,j_) ( A + (i_) + (j_)*lda)
#define dC(i_,j_) (dC + (i_) + (j_)*lddc)
float *T, *T2;
magma_int_t i, i1, i2, ib, ic, jc, nb, mi, ni, nq, nq_i, nw, step;
magma_int_t iinfo, ldwork, lwkopt;
magma_int_t left, notran, lquery;
*info = 0;
left = (side == MagmaLeft);
notran = (trans == MagmaNoTrans);
lquery = (lwork == -1);
/* NQ is the order of Q and NW is the minimum dimension of WORK */
if (left) {
nq = m;
nw = n;
} else {
nq = n;
nw = m;
}
/* Test the input arguments */
if (! left && side != MagmaRight) {
*info = -1;
} else if (! notran && trans != MagmaTrans) {
*info = -2;
} else if (m < 0) {
*info = -3;
} else if (n < 0) {
*info = -4;
} else if (k < 0 || k > nq) {
*info = -5;
} else if (lda < max(1,nq)) {
*info = -7;
} else if (ldc < max(1,m)) {
*info = -10;
} else if (lwork < max(1,nw) && ! lquery) {
*info = -12;
}
if (*info == 0) {
nb = magma_get_sgelqf_nb( min( m, n ));
lwkopt = max(1,nw)*nb;
work[0] = MAGMA_S_MAKE( lwkopt, 0 );
}
if (*info != 0) {
magma_xerbla( __func__, -(*info) );
return *info;
}
else if (lquery) {
return *info;
}
/* Quick return if possible */
if (m == 0 || n == 0 || k == 0) {
work[0] = MAGMA_S_ONE;
return *info;
}
ldwork = nw;
if (nb >= k) {
/* Use CPU code */
lapackf77_sormqr( lapack_side_const(side), lapack_trans_const(trans),
&m, &n, &k, A, &lda, tau, C, &ldc, work, &lwork, &iinfo);
}
else {
/* Use hybrid CPU-GPU code */
/* Allocate work space on the GPU.
* nw*nb for dwork (m or n) by nb
* nq*nb for dV (n or m) by nb
* nb*nb for dT
* lddc*n for dC.
*/
magma_int_t lddc = ((m+31)/32)*32;
float *dwork, *dV, *dT, *dC;
magma_smalloc( &dwork, (nw + nq + nb)*nb + lddc*n );
if ( dwork == NULL ) {
*info = MAGMA_ERR_DEVICE_ALLOC;
return *info;
}
dV = dwork + nw*nb;
dT = dV + nq*nb;
dC = dT + nb*nb;
/* work space on CPU.
* nb*nb for T
* nb*nb for T2, used to save and restore diagonal block of panel */
magma_smalloc_cpu( &T, 2*nb*nb );
if ( T == NULL ) {
magma_free( dwork );
*info = MAGMA_ERR_HOST_ALLOC;
return *info;
}
T2 = T + nb*nb;
/* Copy matrix C from the CPU to the GPU */
magma_ssetmatrix( m, n, C, ldc, dC, lddc );
if ( (left && ! notran) || (! left && notran) ) {
i1 = 0;
i2 = k;
step = nb;
} else {
i1 = ((k - 1) / nb) * nb;
i2 = 0;
step = -nb;
}
// silence "uninitialized" warnings
mi = 0;
ni = 0;
if (left) {
ni = n;
jc = 0;
} else {
mi = m;
ic = 0;
}
for (i = i1; (step < 0 ? i >= i2 : i < i2); i += step) {
ib = min(nb, k - i);
/* Form the triangular factor of the block reflector
H = H(i) H(i+1) . . . H(i+ib-1) */
nq_i = nq - i;
lapackf77_slarft("Forward", "Columnwise", &nq_i, &ib,
A(i,i), &lda, &tau[i], T, &ib);
/* 1) set upper triangle of panel in A to identity,
2) copy the panel from A to the GPU, and
3) restore A */
spanel_to_q( MagmaUpper, ib, A(i,i), lda, T2 );
magma_ssetmatrix( nq_i, ib, A(i,i), lda, dV, nq_i );
sq_to_panel( MagmaUpper, ib, A(i,i), lda, T2 );
if (left) {
/* H or H**H is applied to C(i:m,1:n) */
mi = m - i;
ic = i;
}
else {
/* H or H**H is applied to C(1:m,i:n) */
ni = n - i;
jc = i;
}
/* Apply H or H**H; First copy T to the GPU */
magma_ssetmatrix( ib, ib, T, ib, dT, ib );
magma_slarfb_gpu( side, trans, MagmaForward, MagmaColumnwise,
mi, ni, ib,
dV, nq_i,
dT, ib,
dC(ic,jc), lddc,
dwork, ldwork );
}
magma_sgetmatrix( m, n, dC, lddc, C, ldc );
magma_free( dwork );
magma_free_cpu( T );
}
work[0] = MAGMA_S_MAKE( lwkopt, 0 );
return *info;
} /* magma_sormqr */
/**
Purpose
-------
SGEQRF_OOC computes a QR factorization of a REAL M-by-N matrix A:
A = Q * R. This version does not require work space on the GPU
passed as input. GPU memory is allocated in the routine.
This is an out-of-core (ooc) version that is similar to magma_sgeqrf but
the difference is that this version can use a GPU even if the matrix
does not fit into the GPU memory at once.
Arguments
---------
@param[in]
m INTEGER
The number of rows of the matrix A. M >= 0.
@param[in]
n INTEGER
The number of columns of the matrix A. N >= 0.
@param[in,out]
A REAL array, dimension (LDA,N)
On entry, the M-by-N matrix A.
On exit, the elements on and above the diagonal of the array
contain the min(M,N)-by-N upper trapezoidal matrix R (R is
upper triangular if m >= n); the elements below the diagonal,
with the array TAU, represent the orthogonal matrix Q as a
product of min(m,n) elementary reflectors (see Further
Details).
\n
Higher performance is achieved if A is in pinned memory, e.g.
allocated using magma_malloc_pinned.
@param[in]
lda INTEGER
The leading dimension of the array A. LDA >= max(1,M).
@param[out]
tau REAL array, dimension (min(M,N))
The scalar factors of the elementary reflectors (see Further
Details).
@param[out]
work (workspace) REAL array, dimension (MAX(1,LWORK))
On exit, if INFO = 0, WORK[0] returns the optimal LWORK.
\n
Higher performance is achieved if WORK is in pinned memory, e.g.
allocated using magma_malloc_pinned.
@param[in]
lwork INTEGER
The dimension of the array WORK. LWORK >= N*NB,
where NB can be obtained through magma_get_sgeqrf_nb(M).
\n
If LWORK = -1, then a workspace query is assumed; the routine
only calculates the optimal size of the WORK array, returns
this value as the first entry of the WORK array, and no error
message related to LWORK is issued.
@param[out]
info INTEGER
- = 0: successful exit
- < 0: if INFO = -i, the i-th argument had an illegal value
or another error occured, such as memory allocation failed.
Further Details
---------------
The matrix Q is represented as a product of elementary reflectors
Q = H(1) H(2) . . . H(k), where k = min(m,n).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a real scalar, and v is a real vector with
v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i),
and tau in TAU(i).
@ingroup magma_sgeqrf_comp
********************************************************************/
extern "C" magma_int_t
magma_sgeqrf_ooc(
magma_int_t m, magma_int_t n,
float *A, magma_int_t lda, float *tau,
float *work, magma_int_t lwork,
magma_int_t *info )
{
#define A(a_1,a_2) ( A + (a_2)*(lda) + (a_1))
#define dA(a_1,a_2) (dA + (a_2)*ldda + (a_1))
float *dA, *dwork;
float c_one = MAGMA_S_ONE;
int k, lddwork, ldda;
*info = 0;
int nb = magma_get_sgeqrf_nb(min(m, n));
int lwkopt = n * nb;
work[0] = MAGMA_S_MAKE( (float)lwkopt, 0 );
int lquery = (lwork == -1);
if (m < 0) {
*info = -1;
} else if (n < 0) {
*info = -2;
} else if (lda < max(1,m)) {
*info = -4;
} else if (lwork < max(1,n) && ! lquery) {
*info = -7;
}
if (*info != 0) {
magma_xerbla( __func__, -(*info) );
return *info;
}
else if (lquery) {
return *info;
}
magma_queue_t orig_stream;
magmablasGetKernelStream( &orig_stream );
/* Check how much memory do we have */
size_t freeMem, totalMem;
cudaMemGetInfo( &freeMem, &totalMem );
freeMem /= sizeof(float);
magma_int_t IB, NB = (magma_int_t)(0.8*freeMem/m);
NB = (NB / nb) * nb;
if (NB >= n)
return magma_sgeqrf(m, n, A, lda, tau, work, lwork, info);
k = min(m,n);
if (k == 0) {
work[0] = c_one;
return *info;
}
lddwork = ((NB+31)/32)*32+nb;
ldda = ((m+31)/32)*32;
if (MAGMA_SUCCESS != magma_smalloc( &dA, (NB + nb)*ldda + nb*lddwork )) {
*info = MAGMA_ERR_DEVICE_ALLOC;
return *info;
}
magma_queue_t stream[2];
magma_queue_create( &stream[0] );
magma_queue_create( &stream[1] );
// magmablasSetKernelStream(stream[1]);
float *ptr = dA + ldda * NB;
dwork = dA + ldda*(NB + nb);
/* start the main loop over the blocks that fit in the GPU memory */
for (int i=0; i < n; i += NB) {
IB = min(n-i, NB);
//printf("Processing %5d columns -- %5d to %5d ... \n", IB, i, i+IB);
/* 1. Copy the next part of the matrix to the GPU */
magma_ssetmatrix_async( (m), IB,
A(0,i), lda,
dA(0,0), ldda, stream[0] );
magma_queue_sync( stream[0] );
/* 2. Update it with the previous transformations */
for (int j=0; j < min(i,k); j += nb) {
magma_int_t ib = min(k-j, nb);
/* Get a panel in ptr. */
// 1. Form the triangular factor of the block reflector
// 2. Send it to the GPU.
// 3. Put 0s in the upper triangular part of V.
// 4. Send V to the GPU in ptr.
// 5. Update the matrix.
// 6. Restore the upper part of V.
magma_int_t rows = m-j;
lapackf77_slarft( MagmaForwardStr, MagmaColumnwiseStr,
&rows, &ib, A(j,j), &lda, tau+j, work, &ib);
magma_ssetmatrix_async( ib, ib,
work, ib,
dwork, lddwork, stream[1] );
spanel_to_q(MagmaUpper, ib, A(j,j), lda, work+ib*ib);
magma_ssetmatrix_async( rows, ib,
A(j,j), lda,
ptr, rows, stream[1] );
magma_queue_sync( stream[1] );
magma_slarfb_gpu( MagmaLeft, MagmaConjTrans, MagmaForward, MagmaColumnwise,
rows, IB, ib,
ptr, rows, dwork, lddwork,
dA(j, 0), ldda, dwork+ib, lddwork);
sq_to_panel(MagmaUpper, ib, A(j,j), lda, work+ib*ib);
}
/* 3. Do a QR on the current part */
if (i < k)
magma_sgeqrf2_gpu(m-i, IB, dA(i,0), ldda, tau+i, info);
/* 4. Copy the current part back to the CPU */
magma_sgetmatrix_async( (m), IB,
dA(0,0), ldda,
A(0,i), lda, stream[0] );
}
magma_queue_sync( stream[0] );
magma_queue_destroy( stream[0] );
magma_queue_destroy( stream[1] );
magma_free( dA );
magmablasSetKernelStream( orig_stream );
return *info;
} /* magma_sgeqrf_ooc */
extern "C" magma_int_t
magma_sgeqrf2_mgpu( magma_int_t num_gpus, magma_int_t m, magma_int_t n,
float **dlA, magma_int_t ldda,
float *tau,
magma_int_t *info )
{
/* -- MAGMA (version 1.4.1) --
Univ. of Tennessee, Knoxville
Univ. of California, Berkeley
Univ. of Colorado, Denver
December 2013
Purpose
=======
SGEQRF2_MGPU computes a QR factorization of a real M-by-N matrix A:
A = Q * R. This is a GPU interface of the routine.
Arguments
=========
M (input) INTEGER
The number of rows of the matrix A. M >= 0.
N (input) INTEGER
The number of columns of the matrix A. N >= 0.
dA (input/output) REAL array on the GPU, dimension (LDDA,N)
On entry, the M-by-N matrix dA.
On exit, the elements on and above the diagonal of the array
contain the min(M,N)-by-N upper trapezoidal matrix R (R is
upper triangular if m >= n); the elements below the diagonal,
with the array TAU, represent the orthogonal matrix Q as a
product of min(m,n) elementary reflectors (see Further
Details).
LDDA (input) INTEGER
The leading dimension of the array dA. LDDA >= max(1,M).
To benefit from coalescent memory accesses LDDA must be
dividable by 16.
TAU (output) REAL array, dimension (min(M,N))
The scalar factors of the elementary reflectors (see Further
Details).
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
or another error occured, such as memory allocation failed.
Further Details
===============
The matrix Q is represented as a product of elementary reflectors
Q = H(1) H(2) . . . H(k), where k = min(m,n).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a real scalar, and v is a real vector with
v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i),
and tau in TAU(i).
===================================================================== */
#define dlA(dev, i, j) (dlA[dev] + (i) + (j)*(ldda))
#define hpanel(i) (hpanel + (i))
// set to NULL to make cleanup easy: free(NULL) does nothing.
float *dwork[MagmaMaxGPUs]={NULL}, *dpanel[MagmaMaxGPUs]={NULL};
float *hwork=NULL, *hpanel=NULL;
magma_queue_t stream[MagmaMaxGPUs][2]={{NULL}};
magma_event_t panel_event[MagmaMaxGPUs]={NULL};
magma_int_t i, j, min_mn, dev, ldhpanel, lddwork, rows;
magma_int_t ib, nb;
magma_int_t lhwork, lwork;
magma_int_t panel_dev, i_local, i_nb_local, n_local[MagmaMaxGPUs], la_dev, dpanel_offset;
magma_queue_t cqueue;
magmablasGetKernelStream( &cqueue );
magma_device_t cdevice;
magma_getdevice( &cdevice );
*info = 0;
if (m < 0) {
*info = -1;
} else if (n < 0) {
*info = -2;
} else if (ldda < max(1,m)) {
*info = -4;
}
if (*info != 0) {
magma_xerbla( __func__, -(*info) );
return *info;
}
min_mn = min(m,n);
if (min_mn == 0)
return *info;
nb = magma_get_sgeqrf_nb( m );
/* dwork is (n*nb) --- for T (nb*nb) and slarfb work ((n-nb)*nb) ---
* + dpanel (ldda*nb), on each GPU.
* I think slarfb work could be smaller, max(n_local[:]).
* Oddly, T and slarfb work get stacked on top of each other, both with lddwork=n.
* on GPU that owns panel, set dpanel = dlA(dev,i,i_local).
* on other GPUs, set dpanel = dwork[dev] + dpanel_offset. */
lddwork = n;
dpanel_offset = lddwork*nb;
for( dev=0; dev < num_gpus; dev++ ) {
magma_setdevice( dev );
if ( MAGMA_SUCCESS != magma_smalloc( &(dwork[dev]), (lddwork + ldda)*nb )) {
*info = MAGMA_ERR_DEVICE_ALLOC;
goto CLEANUP;
}
}
/* hwork is MAX( workspace for sgeqrf (n*nb), two copies of T (2*nb*nb) )
* + hpanel (m*nb).
* for last block, need 2*n*nb total. */
ldhpanel = m;
lhwork = max( n*nb, 2*nb*nb );
lwork = max( lhwork + ldhpanel*nb, 2*n*nb );
if ( MAGMA_SUCCESS != magma_smalloc_pinned( &hwork, lwork )) {
*info = MAGMA_ERR_HOST_ALLOC;
goto CLEANUP;
}
hpanel = hwork + lhwork;
/* Set the number of local n for each GPU */
for( dev=0; dev < num_gpus; dev++ ) {
n_local[dev] = ((n/nb)/num_gpus)*nb;
if (dev < (n/nb) % num_gpus)
n_local[dev] += nb;
else if (dev == (n/nb) % num_gpus)
n_local[dev] += n % nb;
}
for( dev=0; dev < num_gpus; dev++ ) {
magma_setdevice( dev );
magma_queue_create( &stream[dev][0] );
magma_queue_create( &stream[dev][1] );
magma_event_create( &panel_event[dev] );
}
if ( nb < min_mn ) {
/* Use blocked code initially */
// Note: as written, ib cannot be < nb.
for( i = 0; i < min_mn-nb; i += nb ) {
/* Set the GPU number that holds the current panel */
panel_dev = (i/nb) % num_gpus;
/* Set the local index where the current panel is (j==i) */
i_local = i/(nb*num_gpus)*nb;
ib = min(min_mn-i, nb);
rows = m-i;
/* Send current panel to the CPU, after panel_event indicates it has been updated */
magma_setdevice( panel_dev );
magma_queue_wait_event( stream[panel_dev][1], panel_event[panel_dev] );
magma_sgetmatrix_async( rows, ib,
dlA(panel_dev, i, i_local), ldda,
hpanel(i), ldhpanel, stream[panel_dev][1] );
magma_queue_sync( stream[panel_dev][1] );
// Factor panel
lapackf77_sgeqrf( &rows, &ib, hpanel(i), &ldhpanel, tau+i,
hwork, &lhwork, info );
if ( *info != 0 ) {
fprintf( stderr, "error %d\n", (int) *info );
}
// Form the triangular factor of the block reflector
// H = H(i) H(i+1) . . . H(i+ib-1)
lapackf77_slarft( MagmaForwardStr, MagmaColumnwiseStr,
&rows, &ib,
hpanel(i), &ldhpanel, tau+i, hwork, &ib );
spanel_to_q( MagmaUpper, ib, hpanel(i), ldhpanel, hwork + ib*ib );
// Send the current panel back to the GPUs
for( dev=0; dev < num_gpus; dev++ ) {
magma_setdevice( dev );
if (dev == panel_dev)
dpanel[dev] = dlA(dev, i, i_local);
else
dpanel[dev] = dwork[dev] + dpanel_offset;
magma_ssetmatrix_async( rows, ib,
hpanel(i), ldhpanel,
dpanel[dev], ldda, stream[dev][0] );
}
for( dev=0; dev < num_gpus; dev++ ) {
magma_setdevice( dev );
magma_queue_sync( stream[dev][0] );
}
// TODO: if spanel_to_q copied whole block, wouldn't need to restore
// -- just send the copy to the GPUs.
// TODO: also, could zero out the lower triangle and use Azzam's larfb w/ gemm.
/* Restore the panel */
sq_to_panel( MagmaUpper, ib, hpanel(i), ldhpanel, hwork + ib*ib );
if (i + ib < n) {
/* Send the T matrix to the GPU. */
for( dev=0; dev < num_gpus; dev++ ) {
magma_setdevice( dev );
magma_ssetmatrix_async( ib, ib,
hwork, ib,
dwork[dev], lddwork, stream[dev][0] );
}
la_dev = (panel_dev+1) % num_gpus;
for( dev=0; dev < num_gpus; dev++ ) {
magma_setdevice( dev );
magmablasSetKernelStream( stream[dev][0] );
if (dev == la_dev && i+nb < min_mn-nb) {
// If not last panel,
// for look-ahead panel, apply H' to A(i:m,i+ib:i+2*ib)
i_nb_local = (i+nb)/(nb*num_gpus)*nb;
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaForward, MagmaColumnwise,
rows, ib, ib,
dpanel[dev], ldda, // V
dwork[dev], lddwork, // T
dlA(dev, i, i_nb_local), ldda, // C
dwork[dev]+ib, lddwork ); // work
magma_event_record( panel_event[dev], stream[dev][0] );
// for trailing matrix, apply H' to A(i:m,i+2*ib:n)
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaForward, MagmaColumnwise,
rows, n_local[dev]-(i_nb_local+ib), ib,
dpanel[dev], ldda, // V
dwork[dev], lddwork, // T
dlA(dev, i, i_nb_local+ib), ldda, // C
dwork[dev]+ib, lddwork ); // work
}
else {
// for trailing matrix, apply H' to A(i:m,i+ib:n)
i_nb_local = i_local;
if (dev <= panel_dev) {
i_nb_local += ib;
}
magma_slarfb_gpu( MagmaLeft, MagmaTrans, MagmaForward, MagmaColumnwise,
rows, n_local[dev]-i_nb_local, ib,
dpanel[dev], ldda, // V
dwork[dev], lddwork, // T
dlA(dev, i, i_nb_local), ldda, // C
dwork[dev]+ib, lddwork ); // work
}
}
// Restore top of panel (after larfb is done)
magma_setdevice( panel_dev );
magma_ssetmatrix_async( ib, ib,
hpanel(i), ldhpanel,
dlA(panel_dev, i, i_local), ldda, stream[panel_dev][0] );
}
}
}
else {
i = 0;
}
/* Use unblocked code to factor the last or only block row. */
if (i < min_mn) {
rows = m-i;
for( j=i; j < n; j += nb ) {
panel_dev = (j/nb) % num_gpus;
i_local = j/(nb*num_gpus)*nb;
ib = min( n-j, nb );
magma_setdevice( panel_dev );
magma_sgetmatrix( rows, ib,
dlA(panel_dev, i, i_local), ldda,
hwork + (j-i)*rows, rows );
}
// needs lwork >= 2*n*nb:
// needs (m-i)*(n-i) for last block row, bounded by nb*n.
// needs (n-i)*nb for sgeqrf work, bounded by n*nb.
ib = n-i; // total columns in block row
lhwork = lwork - ib*rows;
lapackf77_sgeqrf( &rows, &ib, hwork, &rows, tau+i, hwork + ib*rows, &lhwork, info );
if ( *info != 0 ) {
fprintf( stderr, "error %d\n", (int) *info );
}
for( j=i; j < n; j += nb ) {
panel_dev = (j/nb) % num_gpus;
i_local = j/(nb*num_gpus)*nb;
ib = min( n-j, nb );
magma_setdevice( panel_dev );
magma_ssetmatrix( rows, ib,
hwork + (j-i)*rows, rows,
dlA(panel_dev, i, i_local), ldda );
}
}
CLEANUP:
// free(NULL) does nothing.
// check that queues and events are non-zero before destroying them, though.
for( dev=0; dev < num_gpus; dev++ ) {
magma_setdevice( dev );
if ( stream[dev][0] ) { magma_queue_destroy( stream[dev][0] ); }
if ( stream[dev][1] ) { magma_queue_destroy( stream[dev][1] ); }
if ( panel_event[dev] ) { magma_event_destroy( panel_event[dev] ); }
magma_free( dwork[dev] );
}
magma_free_pinned( hwork );
magma_setdevice( cdevice );
magmablasSetKernelStream( cqueue );
return *info;
} /* magma_sgeqrf2_mgpu */
extern "C" magma_int_t
magma_ssytrd_sy2sb( char uplo, magma_int_t n, magma_int_t nb,
float *a, magma_int_t lda,
float *tau,
float *work, magma_int_t lwork,
float *dT,
magma_int_t threads, magma_int_t *info)
{
/* -- MAGMA (version 1.3.0) --
Univ. of Tennessee, Knoxville
Univ. of California, Berkeley
Univ. of Colorado, Denver
November 2012
Purpose
=======
SSYTRD_HE2HB reduces a real symmetric matrix A to real symmetric
band-diagonal form T by an orthogonal similarity transformation:
Q**T * A * Q = T.
This version stores the triangular matrices T used in the accumulated
Householder transformations (I - V T V').
Arguments
=========
UPLO (input) CHARACTER*1
= 'U': Upper triangle of A is stored;
= 'L': Lower triangle of A is stored.
N (input) INTEGER
The order of the matrix A. N >= 0.
A (input/output) REAL array, dimension (LDA,N)
On entry, the symmetric matrix A. If UPLO = 'U', the leading
N-by-N upper triangular part of A contains the upper
triangular part of the matrix A, and the strictly lower
triangular part of A is not referenced. If UPLO = 'L', the
leading N-by-N lower triangular part of A contains the lower
triangular part of the matrix A, and the strictly upper
triangular part of A is not referenced.
On exit, if UPLO = 'U', the Upper band-diagonal of A is
overwritten by the corresponding elements of the
band-diagonal matrix T, and the elements above the band
diagonal, with the array TAU, represent the orthogonal
matrix Q as a product of elementary reflectors; if UPLO
= 'L', the the Lower band-diagonal of A is overwritten by
the corresponding elements of the band-diagonal
matrix T, and the elements below the band-diagonal, with
the array TAU, represent the orthogonal matrix Q as a product
of elementary reflectors. See Further Details.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,N).
TAU (output) REAL array, dimension (N-1)
The scalar factors of the elementary reflectors (see Further
Details).
WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
LWORK (input) INTEGER
The dimension of the array WORK. LWORK >= 1.
For optimum performance LWORK >= N*NB, where NB is the
optimal blocksize.
If LWORK = -1, then a workspace query is assumed; the routine
only calculates the optimal size of the WORK array, returns
this value as the first entry of the WORK array, and no error
message related to LWORK is issued by XERBLA.
dT (output) REAL array on the GPU, dimension N*NB,
where NB is the optimal blocksize.
On exit dT holds the upper triangular matrices T from the
accumulated Householder transformations (I - V T V') used
in the factorization. The nb x nb matrices T are ordered
consecutively in memory one after another.
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
Further Details
===============
If UPLO = 'U', the matrix Q is represented as a product of elementary
reflectors
Q = H(n-1) . . . H(2) H(1).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a real scalar, and v is a real vector with
v(i+1:n) = 0 and v(i) = 1; v(1:i-1) is stored on exit in
A(1:i-1,i+1), and tau in TAU(i).
If UPLO = 'L', the matrix Q is represented as a product of elementary
reflectors
Q = H(1) H(2) . . . H(n-1).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a real scalar, and v is a real vector with
v(1:i) = 0 and v(i+1) = 1; v(i+2:n) is stored on exit in A(i+2:n,i),
and tau in TAU(i).
The contents of A on exit are illustrated by the following examples
with n = 5:
if UPLO = 'U': if UPLO = 'L':
( d e v2 v3 v4 ) ( d )
( d e v3 v4 ) ( e d )
( d e v4 ) ( v1 e d )
( d e ) ( v1 v2 e d )
( d ) ( v1 v2 v3 e d )
where d and e denote diagonal and off-diagonal elements of T, and vi
denotes an element of the vector defining H(i).
===================================================================== */
#define a_ref(a_1,a_2) ( a + ((a_2)-1)*( lda) + (a_1)-1)
#define da_ref(a_1,a_2) (da + ((a_2)-1)*(ldda) + (a_1)-1)
#define tau_ref(a_1) (tau + (a_1)-1)
#define t_ref(a_1) (dT + ((a_1)-1)*(lddt))
char uplo_[2] = {uplo, 0};
int ldda = ((n+31)/32)*32;
int lddt = nb;
float c_neg_one = MAGMA_S_NEG_ONE;
float c_neg_half = MAGMA_S_NEG_HALF;
float c_one = MAGMA_S_ONE ;
float c_zero = MAGMA_S_ZERO;
float d_one = MAGMA_D_ONE;
magma_int_t pm, pn, indi, indj, pk;
magma_int_t pm_old=0, pn_old=0, indi_old=0, indj_old=0;
int i;
int lwkopt;
int lquery;
*info = 0;
int upper = lapackf77_lsame(uplo_, "U");
lquery = lwork == -1;
if (! upper && ! lapackf77_lsame(uplo_, "L")) {
*info = -1;
} else if (n < 0) {
*info = -2;
} else if (lda < max(1,n)) {
*info = -4;
} else if (lwork < 1 && ! lquery) {
*info = -9;
}
if (*info == 0) {
/* Determine the block size. */
lwkopt = n * nb;
MAGMA_S_SET2REAL( work[0], lwkopt );
}
if (*info != 0)
return *info;
else if (lquery)
return *info;
/* Quick return if possible */
if (n == 0) {
work[0] = c_one;
return *info;
}
float *da;
if (MAGMA_SUCCESS != magma_smalloc( &da, (n + 2*nb)*ldda )) {
*info = MAGMA_ERR_DEVICE_ALLOC;
return *info;
}
magma_int_t mklth = min(threads,12);
#if defined(USEMKL)
mkl_set_num_threads(mklth);
#endif
#if defined(USEACML)
omp_set_num_threads(mklth);
#endif
/* Use the first panel of da as work space */
float *dwork = da+n*ldda;
float *dW = dwork + nb*ldda;
#ifdef TRACING
char buf[80];
#endif
cudaStream_t stream[3];
magma_queue_create( &stream[0] );
magma_queue_create( &stream[1] );
stream[2] = 0; // default stream
trace_init( 1, 1, 3, stream );
float *hT = work + lwork - nb*nb;
lwork -= nb*nb;
memset( hT, 0, nb*nb*sizeof(float));
magmablasSetKernelStream( stream[0] );
cudaEvent_t Pupdate_event;
cudaEventCreateWithFlags(&Pupdate_event,cudaEventDisableTiming);
//cudaEventCreate(&Pupdate_event);
if (upper) {
printf("SSYTRD_HE2HB is not yet implemented for upper matrix storage. Exit.\n");
exit(1);
}else {
/* Copy the matrix to the GPU */
if (1 <= n-nb){
trace_gpu_start( 0, 0, "set", "set A" );
magma_ssetmatrix_async( (n-nb), (n-nb),
a_ref(nb+1, nb+1), lda,
da_ref(nb+1, nb+1), ldda, stream[0] );
trace_gpu_end( 0, 0 );
}
/* Reduce the lower triangle of A */
for (i = 1; i <= n-nb; i += nb)
{
indi = i+nb;
indj = i;
pm = n - i - nb + 1;
//pn = min(i+nb-1, n-nb) -i + 1;
pn = nb;
/* Get the current panel (no need for the 1st iteration) */
if (i > 1 ){
// spanel_to_q copy the upper oof diagonal part of
// the matrix to work to be restored later. acctually
// the zero's and one's putted are not used this is only
// because we don't have a function that copy only the
// upper part of A to be restored after copying the
// lookahead panel that has been computted from GPU to CPU.
spanel_to_q(MagmaUpper, pn-1, a_ref(i, i+1), lda, work);
trace_gpu_start( 0, 1, "get", "get panel" );
//magma_queue_sync( stream[0] );
cudaStreamWaitEvent(stream[1], Pupdate_event, 0);
magma_sgetmatrix_async( (pm+pn), pn,
da_ref( i, i), ldda,
a_ref ( i, i), lda, stream[1] );
trace_gpu_end( 0, 1 );
trace_gpu_start( 0, 2, "syr2k", "syr2k" );
magma_ssyr2k(MagmaLower, MagmaNoTrans, pm_old-pn_old, pn_old, c_neg_one,
da_ref(indi_old+pn_old, indj_old), ldda,
dW + pn_old , pm_old, d_one,
da_ref(indi_old+pn_old, indi_old+pn_old), ldda);
trace_gpu_end( 0, 2 );
trace_cpu_start( 0, "sync", "sync on 1" );
magma_queue_sync( stream[1] );
trace_cpu_end( 0 );
sq_to_panel(MagmaUpper, pn-1, a_ref(i, i+1), lda, work);
}
/* ==========================================================
QR factorization on a panel starting nb off of the diagonal.
Prepare the V and T matrices.
========================================================== */
#ifdef TRACING
snprintf( buf, sizeof(buf), "panel %d", i );
#endif
trace_cpu_start( 0, "geqrf", buf );
lapackf77_sgeqrf(&pm, &pn, a_ref(indi, indj), &lda,
tau_ref(i), work, &lwork, info);
/* Form the matrix T */
pk=min(pm,pn);
lapackf77_slarft( MagmaForwardStr, MagmaColumnwiseStr,
&pm, &pk, a_ref(indi, indj), &lda,
tau_ref(i), hT, &nb);
/* Prepare V - put 0s in the upper triangular part of the panel
(and 1s on the diagonal), temporaly storing the original in work */
spanel_to_q(MagmaUpper, pk, a_ref(indi, indj), lda, work);
trace_cpu_end( 0 );
/* Send V from the CPU to the GPU */
trace_gpu_start( 0, 0, "set", "set V and T" );
magma_ssetmatrix_async( pm, pk,
a_ref(indi, indj), lda,
da_ref(indi, indj), ldda, stream[0] );
/* Send the triangular factor T to the GPU */
magma_ssetmatrix_async( pk, pk,
hT, nb,
t_ref(i), lddt, stream[0] );
trace_gpu_end( 0, 0 );
/* ==========================================================
Compute W:
1. X = A (V T)
2. W = X - 0.5* V * (T' * (V' * X))
========================================================== */
/* dwork = V T */
trace_cpu_start( 0, "sync", "sync on 0" );
// this sync is done here to be sure that the copy has been finished
// because below we made a restore sq_to_panel and this restore need
// to ensure that the copy has been finished. we did it here to allow
// overlapp of restore with next gemm and symm.
magma_queue_sync( stream[0] );
trace_cpu_end( 0 );
trace_gpu_start( 0, 2, "gemm", "work = V*T" );
magma_sgemm(MagmaNoTrans, MagmaNoTrans, pm, pk, pk,
c_one, da_ref(indi, indj), ldda,
t_ref(i), lddt,
c_zero, dwork, pm);
trace_gpu_end( 0, 2 );
/* dW = X = A*V*T. dW = A*dwork */
trace_gpu_start( 0, 2, "symm", "X = A*work" );
magma_ssymm(MagmaLeft, uplo, pm, pk,
c_one, da_ref(indi, indi), ldda,
dwork, pm,
c_zero, dW, pm);
trace_gpu_end( 0, 2 );
/* restore the panel */
sq_to_panel(MagmaUpper, pk, a_ref(indi, indj), lda, work);
/* dwork = V*T already ==> dwork' = T'*V'
* compute T'*V'*X ==> dwork'*W ==>
* dwork + pm*nb = ((T' * V') * X) = dwork' * X = dwork' * W */
trace_gpu_start( 0, 2, "gemm", "work = T'*V'*X" );
magma_sgemm(MagmaTrans, MagmaNoTrans, pk, pk, pm,
c_one, dwork, pm,
dW, pm,
c_zero, dwork + pm*nb, nb);
trace_gpu_end( 0, 2 );
/* W = X - 0.5 * V * T'*V'*X
* = X - 0.5 * V * (dwork + pm*nb) = W - 0.5 * V * (dwork + pm*nb) */
trace_gpu_start( 0, 2, "gemm", "W = X - 0.5*V*(T'*V'*X)" );
magma_sgemm(MagmaNoTrans, MagmaNoTrans, pm, pk, pk,
c_neg_half, da_ref(indi, indj), ldda,
dwork + pm*nb, nb,
c_one, dW, pm);
trace_gpu_end( 0, 2 );
/* ==========================================================
Update the unreduced submatrix A(i+ib:n,i+ib:n), using
an update of the form: A := A - V*W' - W*V'
========================================================== */
if (i + nb <= n-nb){
/* There would be next iteration;
do lookahead - update the next panel */
trace_gpu_start( 0, 2, "gemm", "gemm 4 next panel left" );
magma_sgemm(MagmaNoTrans, MagmaTrans, pm, pn, pn, c_neg_one,
da_ref(indi, indj), ldda,
dW , pm, c_one,
da_ref(indi, indi), ldda);
trace_gpu_end( 0, 2 );
trace_gpu_start( 0, 2, "gemm", "gemm 5 next panel right" );
magma_sgemm(MagmaNoTrans, MagmaTrans, pm, pn, pn, c_neg_one,
dW , pm,
da_ref(indi, indj), ldda, c_one,
da_ref(indi, indi), ldda);
trace_gpu_end( 0, 2 );
cudaEventRecord(Pupdate_event, stream[0]);
}
else {
/* no look-ahead as this is last iteration */
trace_gpu_start( 0, 2, "syr2k", "syr2k last iteration" );
magma_ssyr2k(MagmaLower, MagmaNoTrans, pk, pk, c_neg_one,
da_ref(indi, indj), ldda,
dW , pm, d_one,
da_ref(indi, indi), ldda);
trace_gpu_end( 0, 2 );
}
indi_old = indi;
indj_old = indj;
pm_old = pm;
pn_old = pn;
} // end loop for(i)
/* Send the last block to the CPU */
pk = min(pm,pn);
if (1 <= n-nb){
spanel_to_q(MagmaUpper, pk-1, a_ref(n-pk+1, n-pk+2), lda, work);
trace_gpu_start( 0, 2, "get", "get last block" );
magma_sgetmatrix( pk, pk,
da_ref(n-pk+1, n-pk+1), ldda,
a_ref(n-pk+1, n-pk+1), lda );
trace_gpu_end( 0, 2 );
sq_to_panel(MagmaUpper, pk-1, a_ref(n-pk+1, n-pk+2), lda, work);
}
}// end of LOWER
trace_finalize( "ssytrd_sy2sb.svg", "trace.css" );
cudaEventDestroy(Pupdate_event);
magma_queue_destroy( stream[0] );
magma_queue_destroy( stream[1] );
magma_free( da );
MAGMA_S_SET2REAL( work[0], lwkopt );
magmablasSetKernelStream( 0 );
#if defined(USEMKL)
mkl_set_num_threads(1);
#endif
#if defined(USEACML)
omp_set_num_threads(1);
#endif
return *info;
} /* ssytrd_sy2sb_ */
