diff options
| author | tracierenea <tracie.perez@mavs.uta.edu> | 2016-03-28 20:49:53 -0500 |
|---|---|---|
| committer | tracierenea <tracie.perez@mavs.uta.edu> | 2016-03-28 20:49:53 -0500 |
| commit | aef116e28d02a39a7e30e937574cb35876c15b5b (patch) | |
| tree | 5bde4d8e48c0e147d22c865b7e98b53e2dac8de5 /gr-fec | |
| parent | 7d2c8b16c3764207e9de1190bbfd7e051b8257e4 (diff) | |
gr-fec: Fix memory allocation issue during encoding.
I think that declaring these temporary matrix variables in the header (and then allocating memory for them in the constructor) is problematic when using parallelism = 1 or 2, as is the case when using the BER Curve Gen./Sink blocks.
When parallelism is in effect, there are multiple "sub" flowgraphs in process and therefore multiple, probably very-close-to-simultaneous, calls to encode(). I think what's happening is that these temp matrices are being overwritten in memory by the next call to encode() before the current call to encode() is done with them.
I know that such repeated allocate/free calls in the encode() function is not ideal or efficient, I can't think of a better way to do this (for now) and allow for parallelism.
With this change, these matrices are no longer member variables of the class, so I've removed the "d_" prefix from the variable names.
Diffstat (limited to 'gr-fec')
| -rw-r--r-- | gr-fec/lib/ldpc_H_matrix_impl.cc | 83 | ||||
| -rw-r--r-- | gr-fec/lib/ldpc_H_matrix_impl.h | 4 |
2 files changed, 48 insertions, 39 deletions
diff --git a/gr-fec/lib/ldpc_H_matrix_impl.cc b/gr-fec/lib/ldpc_H_matrix_impl.cc index ae6fb9a0e1..4d37899ba6 100644 --- a/gr-fec/lib/ldpc_H_matrix_impl.cc +++ b/gr-fec/lib/ldpc_H_matrix_impl.cc @@ -67,16 +67,6 @@ namespace gr { // encoder) d_par_bits_last = false; - d_s = gsl_matrix_alloc(d_k, 1); - d_temp1 = gsl_matrix_alloc(B()->size1, d_s->size2); - d_temp2 = gsl_matrix_alloc(T()->size1, 1); - d_temp3 = gsl_matrix_alloc(E()->size1, d_temp2->size2); - d_temp4 = gsl_matrix_alloc(D()->size1, d_s->size2); - d_temp5 = gsl_matrix_alloc(d_temp4->size1, d_temp3->size2); - d_p1 = gsl_matrix_alloc(T()->size1, 1); - d_p2 = gsl_matrix_alloc(phi_inverse()->size1, d_temp5->size2); - d_temp6 = gsl_matrix_alloc(A()->size1, d_p2->size2); - d_temp7 = gsl_matrix_alloc(d_temp6->size1, d_temp1->size2); } // Constructor const gsl_matrix* @@ -259,42 +249,75 @@ namespace gr { ldpc_H_matrix_impl::encode(unsigned char *outbuffer, const unsigned char *inbuffer) const { + + // Temporary matrix for storing stages of encoding. + gsl_matrix *s, *p1, *p2; + gsl_matrix *temp1, *temp2, *temp3, *temp4, *temp5, *temp6, *temp7; + unsigned int index, k = d_k; + s = gsl_matrix_alloc(k, 1); for (index = 0; index < k; index++) { double value = static_cast<double>(inbuffer[index]); - gsl_matrix_set(d_s, index, 0, value); + gsl_matrix_set(s, index, 0, value); } // Solve for p2 (parity part). By using back substitution, // the overall complexity of determining p2 is O(n + g^2). - mult_matrices_mod2(d_temp1, B(), d_s); - back_solve_mod2(d_temp2, T(), d_temp1); - mult_matrices_mod2(d_temp3, E(), d_temp2); - mult_matrices_mod2(d_temp4, D(), d_s); - add_matrices_mod2(d_temp5, d_temp4, d_temp3); - mult_matrices_mod2(d_p2, phi_inverse(), d_temp5); + temp1 = gsl_matrix_alloc(B()->size1, s->size2); + mult_matrices_mod2(temp1, B(), s); + + temp2 = gsl_matrix_alloc(T()->size1, 1); + back_solve_mod2(temp2, T(), temp1); + + temp3 = gsl_matrix_alloc(E()->size1, temp2->size2); + mult_matrices_mod2(temp3, E(), temp2); + + temp4 = gsl_matrix_alloc(D()->size1, s->size2); + mult_matrices_mod2(temp4, D(), s); + + temp5 = gsl_matrix_alloc(temp4->size1, temp3->size2); + add_matrices_mod2(temp5, temp4, temp3); + + p2 = gsl_matrix_alloc(phi_inverse()->size1, temp5->size2); + mult_matrices_mod2(p2, phi_inverse(), temp5); // Solve for p1 (parity part). By using back substitution, // the overall complexity of determining p1 is O(n). - mult_matrices_mod2(d_temp6, A(), d_p2); - add_matrices_mod2(d_temp7, d_temp6, d_temp1); - back_solve_mod2(d_p1, T(), d_temp7); + temp6 = gsl_matrix_alloc(A()->size1, p2->size2); + mult_matrices_mod2(temp6, A(), p2); + + temp7 = gsl_matrix_alloc(temp6->size1, temp1->size2); + add_matrices_mod2(temp7, temp6, temp1); + + p1 = gsl_matrix_alloc(T()->size1, 1); + back_solve_mod2(p1, T(), temp7); // Populate the codeword to be output - unsigned int p1_length = (*d_p1).size1; - unsigned int p2_length = (*d_p2).size1; + unsigned int p1_length = (*p1).size1; + unsigned int p2_length = (*p2).size1; for (index = 0; index < p1_length; index++) { - int value = gsl_matrix_get(d_p1, index, 0); + int value = gsl_matrix_get(p1, index, 0); outbuffer[index] = value; } for (index = 0; index < p2_length; index++) { - int value = gsl_matrix_get(d_p2, index, 0); + int value = gsl_matrix_get(p2, index, 0); outbuffer[p1_length+index] = value; } for (index = 0; index < k; index++) { - int value = gsl_matrix_get(d_s, index, 0); + int value = gsl_matrix_get(s, index, 0); outbuffer[p1_length+p2_length+index] = value; } + + // Free temporary matrices + gsl_matrix_free(temp1); + gsl_matrix_free(temp2); + gsl_matrix_free(temp3); + gsl_matrix_free(temp4); + gsl_matrix_free(temp5); + gsl_matrix_free(temp6); + gsl_matrix_free(temp7); + gsl_matrix_free(p1); + gsl_matrix_free(p2); } @@ -413,16 +436,6 @@ namespace gr { ldpc_H_matrix_impl::~ldpc_H_matrix_impl() { - // Free temporary matrices - gsl_matrix_free(d_temp1); - gsl_matrix_free(d_temp2); - gsl_matrix_free(d_temp3); - gsl_matrix_free(d_temp4); - gsl_matrix_free(d_temp5); - gsl_matrix_free(d_temp6); - gsl_matrix_free(d_temp7); - gsl_matrix_free(d_p1); - gsl_matrix_free(d_p2); // Call the gsl_matrix_free function to free memory. gsl_matrix_free (d_phi_inverse_ptr); diff --git a/gr-fec/lib/ldpc_H_matrix_impl.h b/gr-fec/lib/ldpc_H_matrix_impl.h index b4893ced7d..89ea4de49b 100644 --- a/gr-fec/lib/ldpc_H_matrix_impl.h +++ b/gr-fec/lib/ldpc_H_matrix_impl.h @@ -43,10 +43,6 @@ namespace gr { gsl_matrix_view d_T_view; gsl_matrix *d_phi_inverse_ptr; - // Temporary matrix for storing stages of encoding. - gsl_matrix *d_s, *d_p1, *d_p2; - gsl_matrix *d_temp1, *d_temp2, *d_temp3, *d_temp4, *d_temp5, *d_temp6, *d_temp7; - //! Sets the submatrix variables needed for encoding void set_parameters_for_encoding(); |