examples: reformat using new code style

Signed-off-by: Marcel Cornu <marcel.d.cornu@intel.com>
This commit is contained in:
Marcel Cornu
2024-04-19 17:09:13 +01:00
committed by Pablo de Lara
parent 300260a4d9
commit 9d99f8215d
3 changed files with 866 additions and 858 deletions

View File

@@ -31,7 +31,7 @@
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include "erasure_code.h" // use <isa-l.h> instead when linking against installed
#include "erasure_code.h" // use <isa-l.h> instead when linking against installed
#include "test.h"
#define MMAX 255
@@ -40,467 +40,463 @@
typedef unsigned char u8;
int verbose = 0;
int usage(void)
int
usage(void)
{
fprintf(stderr,
"Usage: ec_piggyback_example [options]\n"
" -h Help\n"
" -k <val> Number of source fragments\n"
" -p <val> Number of parity fragments\n"
" -l <val> Length of fragments\n"
" -e <val> Simulate erasure on frag index val. Zero based. Can be repeated.\n"
" -v Verbose\n"
" -b Run timed benchmark\n"
" -s Toggle use of sparse matrix opt\n"
" -r <seed> Pick random (k, p) with seed\n");
exit(0);
fprintf(stderr,
"Usage: ec_piggyback_example [options]\n"
" -h Help\n"
" -k <val> Number of source fragments\n"
" -p <val> Number of parity fragments\n"
" -l <val> Length of fragments\n"
" -e <val> Simulate erasure on frag index val. Zero based. Can be repeated.\n"
" -v Verbose\n"
" -b Run timed benchmark\n"
" -s Toggle use of sparse matrix opt\n"
" -r <seed> Pick random (k, p) with seed\n");
exit(0);
}
// Cauchy-based matrix
void gf_gen_full_pb_cauchy_matrix(u8 * a, int m, int k)
void
gf_gen_full_pb_cauchy_matrix(u8 *a, int m, int k)
{
int i, j, p = m - k;
int i, j, p = m - k;
// Identity matrix in top k x k to indicate a symmetric code
memset(a, 0, k * m);
for (i = 0; i < k; i++)
a[k * i + i] = 1;
// Identity matrix in top k x k to indicate a symmetric code
memset(a, 0, k * m);
for (i = 0; i < k; i++)
a[k * i + i] = 1;
for (i = k; i < (k + p / 2); i++) {
for (j = 0; j < k / 2; j++)
a[k * i + j] = gf_inv(i ^ j);
for (; j < k; j++)
a[k * i + j] = 0;
}
for (; i < m; i++) {
for (j = 0; j < k / 2; j++)
a[k * i + j] = 0;
for (; j < k; j++)
a[k * i + j] = gf_inv((i - p / 2) ^ (j - k / 2));
}
for (i = k; i < (k + p / 2); i++) {
for (j = 0; j < k / 2; j++)
a[k * i + j] = gf_inv(i ^ j);
for (; j < k; j++)
a[k * i + j] = 0;
}
for (; i < m; i++) {
for (j = 0; j < k / 2; j++)
a[k * i + j] = 0;
for (; j < k; j++)
a[k * i + j] = gf_inv((i - p / 2) ^ (j - k / 2));
}
// Fill in mixture of B parity depending on a few localized A sources
int r = 0, c = 0;
int repeat_len = k / (p - 2);
int parity_rows = p / 2;
// Fill in mixture of B parity depending on a few localized A sources
int r = 0, c = 0;
int repeat_len = k / (p - 2);
int parity_rows = p / 2;
for (i = 1 + k + parity_rows; i < m; i++, r++) {
if (r == (parity_rows - 1) - ((k / 2 % (parity_rows - 1))))
repeat_len++;
for (i = 1 + k + parity_rows; i < m; i++, r++) {
if (r == (parity_rows - 1) - ((k / 2 % (parity_rows - 1))))
repeat_len++;
for (j = 0; j < repeat_len; j++, c++)
a[k * i + c] = gf_inv((k + 1) ^ c);
}
for (j = 0; j < repeat_len; j++, c++)
a[k * i + c] = gf_inv((k + 1) ^ c);
}
}
// Vandermonde based matrix - not recommended due to limits when invertable
void gf_gen_full_pb_vand_matrix(u8 * a, int m, int k)
void
gf_gen_full_pb_vand_matrix(u8 *a, int m, int k)
{
int i, j, p = m - k;
unsigned char q, gen = 1;
int i, j, p = m - k;
unsigned char q, gen = 1;
// Identity matrix in top k x k to indicate a symmetric code
memset(a, 0, k * m);
for (i = 0; i < k; i++)
a[k * i + i] = 1;
// Identity matrix in top k x k to indicate a symmetric code
memset(a, 0, k * m);
for (i = 0; i < k; i++)
a[k * i + i] = 1;
for (i = k; i < (k + (p / 2)); i++) {
q = 1;
for (j = 0; j < k / 2; j++) {
a[k * i + j] = q;
q = gf_mul(q, gen);
}
for (; j < k; j++)
a[k * i + j] = 0;
gen = gf_mul(gen, 2);
}
gen = 1;
for (; i < m; i++) {
q = 1;
for (j = 0; j < k / 2; j++) {
a[k * i + j] = 0;
}
for (; j < k; j++) {
a[k * i + j] = q;
q = gf_mul(q, gen);
}
gen = gf_mul(gen, 2);
}
for (i = k; i < (k + (p / 2)); i++) {
q = 1;
for (j = 0; j < k / 2; j++) {
a[k * i + j] = q;
q = gf_mul(q, gen);
}
for (; j < k; j++)
a[k * i + j] = 0;
gen = gf_mul(gen, 2);
}
gen = 1;
for (; i < m; i++) {
q = 1;
for (j = 0; j < k / 2; j++) {
a[k * i + j] = 0;
}
for (; j < k; j++) {
a[k * i + j] = q;
q = gf_mul(q, gen);
}
gen = gf_mul(gen, 2);
}
// Fill in mixture of B parity depending on a few localized A sources
int r = 0, c = 0;
int repeat_len = k / (p - 2);
int parity_rows = p / 2;
// Fill in mixture of B parity depending on a few localized A sources
int r = 0, c = 0;
int repeat_len = k / (p - 2);
int parity_rows = p / 2;
for (i = 1 + k + parity_rows; i < m; i++, r++) {
if (r == (parity_rows - 1) - ((k / 2 % (parity_rows - 1))))
repeat_len++;
for (i = 1 + k + parity_rows; i < m; i++, r++) {
if (r == (parity_rows - 1) - ((k / 2 % (parity_rows - 1))))
repeat_len++;
for (j = 0; j < repeat_len; j++)
a[k * i + c++] = 1;
}
for (j = 0; j < repeat_len; j++)
a[k * i + c++] = 1;
}
}
void print_matrix(int m, int k, unsigned char *s, const char *msg)
void
print_matrix(int m, int k, unsigned char *s, const char *msg)
{
int i, j;
int i, j;
printf("%s:\n", msg);
for (i = 0; i < m; i++) {
printf("%3d- ", i);
for (j = 0; j < k; j++) {
printf(" %2x", 0xff & s[j + (i * k)]);
}
printf("\n");
}
printf("\n");
printf("%s:\n", msg);
for (i = 0; i < m; i++) {
printf("%3d- ", i);
for (j = 0; j < k; j++) {
printf(" %2x", 0xff & s[j + (i * k)]);
}
printf("\n");
}
printf("\n");
}
void print_list(int n, unsigned char *s, const char *msg)
void
print_list(int n, unsigned char *s, const char *msg)
{
int i;
if (!verbose)
return;
int i;
if (!verbose)
return;
printf("%s: ", msg);
for (i = 0; i < n; i++)
printf(" %d", s[i]);
printf("\n");
printf("%s: ", msg);
for (i = 0; i < n; i++)
printf(" %d", s[i]);
printf("\n");
}
static int gf_gen_decode_matrix(u8 * encode_matrix,
u8 * decode_matrix,
u8 * invert_matrix,
u8 * temp_matrix,
u8 * decode_index,
u8 * frag_err_list, int nerrs, int k, int m);
static int
gf_gen_decode_matrix(u8 *encode_matrix, u8 *decode_matrix, u8 *invert_matrix, u8 *temp_matrix,
u8 *decode_index, u8 *frag_err_list, int nerrs, int k, int m);
int main(int argc, char *argv[])
int
main(int argc, char *argv[])
{
int i, j, m, c, e, ret;
int k = 10, p = 4, len = 8 * 1024; // Default params
int nerrs = 0;
int benchmark = 0;
int sparse_matrix_opt = 1;
int i, j, m, c, e, ret;
int k = 10, p = 4, len = 8 * 1024; // Default params
int nerrs = 0;
int benchmark = 0;
int sparse_matrix_opt = 1;
// Fragment buffer pointers
u8 *frag_ptrs[MMAX];
u8 *parity_ptrs[KMAX];
u8 *recover_srcs[KMAX];
u8 *recover_outp[KMAX];
u8 frag_err_list[MMAX];
// Fragment buffer pointers
u8 *frag_ptrs[MMAX];
u8 *parity_ptrs[KMAX];
u8 *recover_srcs[KMAX];
u8 *recover_outp[KMAX];
u8 frag_err_list[MMAX];
// Coefficient matrices
u8 *encode_matrix, *decode_matrix;
u8 *invert_matrix, *temp_matrix;
u8 *g_tbls;
u8 decode_index[MMAX];
// Coefficient matrices
u8 *encode_matrix, *decode_matrix;
u8 *invert_matrix, *temp_matrix;
u8 *g_tbls;
u8 decode_index[MMAX];
if (argc == 1)
for (i = 0; i < p; i++)
frag_err_list[nerrs++] = rand() % (k + p);
if (argc == 1)
for (i = 0; i < p; i++)
frag_err_list[nerrs++] = rand() % (k + p);
while ((c = getopt(argc, argv, "k:p:l:e:r:hvbs")) != -1) {
switch (c) {
case 'k':
k = atoi(optarg);
break;
case 'p':
p = atoi(optarg);
break;
case 'l':
len = atoi(optarg);
if (len < 0)
usage();
break;
case 'e':
e = atoi(optarg);
frag_err_list[nerrs++] = e;
break;
case 'r':
srand(atoi(optarg));
k = (rand() % MMAX) / 4;
k = (k < 2) ? 2 : k;
p = (rand() % (MMAX - k)) / 4;
p = (p < 2) ? 2 : p;
for (i = 0; i < k && nerrs < p; i++)
if (rand() & 1)
frag_err_list[nerrs++] = i;
break;
case 'v':
verbose++;
break;
case 'b':
benchmark = 1;
break;
case 's':
sparse_matrix_opt = !sparse_matrix_opt;
break;
case 'h':
default:
usage();
break;
}
}
m = k + p;
while ((c = getopt(argc, argv, "k:p:l:e:r:hvbs")) != -1) {
switch (c) {
case 'k':
k = atoi(optarg);
break;
case 'p':
p = atoi(optarg);
break;
case 'l':
len = atoi(optarg);
if (len < 0)
usage();
break;
case 'e':
e = atoi(optarg);
frag_err_list[nerrs++] = e;
break;
case 'r':
srand(atoi(optarg));
k = (rand() % MMAX) / 4;
k = (k < 2) ? 2 : k;
p = (rand() % (MMAX - k)) / 4;
p = (p < 2) ? 2 : p;
for (i = 0; i < k && nerrs < p; i++)
if (rand() & 1)
frag_err_list[nerrs++] = i;
break;
case 'v':
verbose++;
break;
case 'b':
benchmark = 1;
break;
case 's':
sparse_matrix_opt = !sparse_matrix_opt;
break;
case 'h':
default:
usage();
break;
}
}
m = k + p;
// Check for valid parameters
if (m > (MMAX / 2) || k > (KMAX / 2) || m < 0 || p < 2 || k < 1) {
printf(" Input test parameter error m=%d, k=%d, p=%d, erasures=%d\n",
m, k, p, nerrs);
usage();
}
if (nerrs > p) {
printf(" Number of erasures chosen exceeds power of code erasures=%d p=%d\n",
nerrs, p);
}
for (i = 0; i < nerrs; i++) {
if (frag_err_list[i] >= m)
printf(" fragment %d not in range\n", frag_err_list[i]);
}
// Check for valid parameters
if (m > (MMAX / 2) || k > (KMAX / 2) || m < 0 || p < 2 || k < 1) {
printf(" Input test parameter error m=%d, k=%d, p=%d, erasures=%d\n", m, k, p,
nerrs);
usage();
}
if (nerrs > p) {
printf(" Number of erasures chosen exceeds power of code erasures=%d p=%d\n", nerrs,
p);
}
for (i = 0; i < nerrs; i++) {
if (frag_err_list[i] >= m)
printf(" fragment %d not in range\n", frag_err_list[i]);
}
printf("ec_piggyback_example:\n");
printf("ec_piggyback_example:\n");
/*
* One simple way to implement piggyback codes is to keep a 2x wide matrix
* that covers the how each parity is related to both A and B sources. This
* keeps it easy to generalize in parameters m,k and the resulting sparse
* matrix multiplication can be optimized by pre-removal of zero items.
*/
/*
* One simple way to implement piggyback codes is to keep a 2x wide matrix
* that covers the how each parity is related to both A and B sources. This
* keeps it easy to generalize in parameters m,k and the resulting sparse
* matrix multiplication can be optimized by pre-removal of zero items.
*/
int k2 = 2 * k;
int p2 = 2 * p;
int m2 = k2 + p2;
int nerrs2 = nerrs;
int k2 = 2 * k;
int p2 = 2 * p;
int m2 = k2 + p2;
int nerrs2 = nerrs;
encode_matrix = malloc(m2 * k2);
decode_matrix = malloc(m2 * k2);
invert_matrix = malloc(m2 * k2);
temp_matrix = malloc(m2 * k2);
g_tbls = malloc(k2 * p2 * 32);
encode_matrix = malloc(m2 * k2);
decode_matrix = malloc(m2 * k2);
invert_matrix = malloc(m2 * k2);
temp_matrix = malloc(m2 * k2);
g_tbls = malloc(k2 * p2 * 32);
if (encode_matrix == NULL || decode_matrix == NULL
|| invert_matrix == NULL || temp_matrix == NULL || g_tbls == NULL) {
printf("Test failure! Error with malloc\n");
return -1;
}
// Allocate the src fragments
for (i = 0; i < k; i++) {
if (NULL == (frag_ptrs[i] = malloc(len))) {
printf("alloc error: Fail\n");
return -1;
}
}
// Allocate the parity fragments
for (i = 0; i < p2; i++) {
if (NULL == (parity_ptrs[i] = malloc(len / 2))) {
printf("alloc error: Fail\n");
return -1;
}
}
if (encode_matrix == NULL || decode_matrix == NULL || invert_matrix == NULL ||
temp_matrix == NULL || g_tbls == NULL) {
printf("Test failure! Error with malloc\n");
return -1;
}
// Allocate the src fragments
for (i = 0; i < k; i++) {
if (NULL == (frag_ptrs[i] = malloc(len))) {
printf("alloc error: Fail\n");
return -1;
}
}
// Allocate the parity fragments
for (i = 0; i < p2; i++) {
if (NULL == (parity_ptrs[i] = malloc(len / 2))) {
printf("alloc error: Fail\n");
return -1;
}
}
// Allocate buffers for recovered data
for (i = 0; i < p2; i++) {
if (NULL == (recover_outp[i] = malloc(len / 2))) {
printf("alloc error: Fail\n");
return -1;
}
}
// Allocate buffers for recovered data
for (i = 0; i < p2; i++) {
if (NULL == (recover_outp[i] = malloc(len / 2))) {
printf("alloc error: Fail\n");
return -1;
}
}
// Fill sources with random data
for (i = 0; i < k; i++)
for (j = 0; j < len; j++)
frag_ptrs[i][j] = rand();
// Fill sources with random data
for (i = 0; i < k; i++)
for (j = 0; j < len; j++)
frag_ptrs[i][j] = rand();
printf(" encode (m,k,p)=(%d,%d,%d) len=%d\n", m, k, p, len);
printf(" encode (m,k,p)=(%d,%d,%d) len=%d\n", m, k, p, len);
// Pick an encode matrix.
gf_gen_full_pb_cauchy_matrix(encode_matrix, m2, k2);
// Pick an encode matrix.
gf_gen_full_pb_cauchy_matrix(encode_matrix, m2, k2);
if (verbose)
print_matrix(m2, k2, encode_matrix, "encode matrix");
if (verbose)
print_matrix(m2, k2, encode_matrix, "encode matrix");
// Initialize g_tbls from encode matrix
ec_init_tables(k2, p2, &encode_matrix[k2 * k2], g_tbls);
// Initialize g_tbls from encode matrix
ec_init_tables(k2, p2, &encode_matrix[k2 * k2], g_tbls);
// Fold A and B into single list of fragments
for (i = 0; i < k; i++)
frag_ptrs[i + k] = &frag_ptrs[i][len / 2];
// Fold A and B into single list of fragments
for (i = 0; i < k; i++)
frag_ptrs[i + k] = &frag_ptrs[i][len / 2];
if (!sparse_matrix_opt) {
// Standard encode using no assumptions on the encode matrix
if (!sparse_matrix_opt) {
// Standard encode using no assumptions on the encode matrix
// Generate EC parity blocks from sources
ec_encode_data(len / 2, k2, p2, g_tbls, frag_ptrs, parity_ptrs);
// Generate EC parity blocks from sources
ec_encode_data(len / 2, k2, p2, g_tbls, frag_ptrs, parity_ptrs);
if (benchmark) {
struct perf start;
BENCHMARK(&start, BENCHMARK_TIME,
ec_encode_data(len / 2, k2, p2, g_tbls, frag_ptrs,
parity_ptrs));
printf("ec_piggyback_encode_std: ");
perf_print(start, m2 * len / 2);
}
} else {
// Sparse matrix optimization - use fact that input matrix is sparse
if (benchmark) {
struct perf start;
BENCHMARK(&start, BENCHMARK_TIME,
ec_encode_data(len / 2, k2, p2, g_tbls, frag_ptrs, parity_ptrs));
printf("ec_piggyback_encode_std: ");
perf_print(start, m2 * len / 2);
}
} else {
// Sparse matrix optimization - use fact that input matrix is sparse
// Keep an encode matrix with some zero elements removed
u8 *encode_matrix_faster, *g_tbls_faster;
encode_matrix_faster = malloc(m * k);
g_tbls_faster = malloc(k * p * 32);
if (encode_matrix_faster == NULL || g_tbls_faster == NULL) {
printf("Test failure! Error with malloc\n");
return -1;
}
// Keep an encode matrix with some zero elements removed
u8 *encode_matrix_faster, *g_tbls_faster;
encode_matrix_faster = malloc(m * k);
g_tbls_faster = malloc(k * p * 32);
if (encode_matrix_faster == NULL || g_tbls_faster == NULL) {
printf("Test failure! Error with malloc\n");
return -1;
}
/*
* Pack with only the part that we know are non-zero. Alternatively
* we could search and keep track of non-zero elements but for
* simplicity we just skip the lower quadrant.
*/
for (i = k, j = k2; i < m; i++, j++)
memcpy(&encode_matrix_faster[k * i], &encode_matrix[k2 * j], k);
/*
* Pack with only the part that we know are non-zero. Alternatively
* we could search and keep track of non-zero elements but for
* simplicity we just skip the lower quadrant.
*/
for (i = k, j = k2; i < m; i++, j++)
memcpy(&encode_matrix_faster[k * i], &encode_matrix[k2 * j], k);
if (verbose) {
print_matrix(p, k, &encode_matrix_faster[k * k],
"encode via sparse-opt");
print_matrix(p2 / 2, k2, &encode_matrix[(k2 + p2 / 2) * k2],
"encode via sparse-opt");
}
// Initialize g_tbls from encode matrix
ec_init_tables(k, p, &encode_matrix_faster[k * k], g_tbls_faster);
if (verbose) {
print_matrix(p, k, &encode_matrix_faster[k * k], "encode via sparse-opt");
print_matrix(p2 / 2, k2, &encode_matrix[(k2 + p2 / 2) * k2],
"encode via sparse-opt");
}
// Initialize g_tbls from encode matrix
ec_init_tables(k, p, &encode_matrix_faster[k * k], g_tbls_faster);
// Generate EC parity blocks from sources
ec_encode_data(len / 2, k, p, g_tbls_faster, frag_ptrs, parity_ptrs);
ec_encode_data(len / 2, k2, p, &g_tbls[k2 * p * 32], frag_ptrs,
&parity_ptrs[p]);
// Generate EC parity blocks from sources
ec_encode_data(len / 2, k, p, g_tbls_faster, frag_ptrs, parity_ptrs);
ec_encode_data(len / 2, k2, p, &g_tbls[k2 * p * 32], frag_ptrs, &parity_ptrs[p]);
if (benchmark) {
struct perf start;
BENCHMARK(&start, BENCHMARK_TIME,
ec_encode_data(len / 2, k, p, g_tbls_faster, frag_ptrs,
parity_ptrs);
ec_encode_data(len / 2, k2, p, &g_tbls[k2 * p * 32],
frag_ptrs, &parity_ptrs[p]));
printf("ec_piggyback_encode_sparse: ");
perf_print(start, m2 * len / 2);
}
}
if (benchmark) {
struct perf start;
BENCHMARK(&start, BENCHMARK_TIME,
ec_encode_data(len / 2, k, p, g_tbls_faster, frag_ptrs,
parity_ptrs);
ec_encode_data(len / 2, k2, p, &g_tbls[k2 * p * 32], frag_ptrs,
&parity_ptrs[p]));
printf("ec_piggyback_encode_sparse: ");
perf_print(start, m2 * len / 2);
}
}
if (nerrs <= 0)
return 0;
if (nerrs <= 0)
return 0;
printf(" recover %d fragments\n", nerrs);
printf(" recover %d fragments\n", nerrs);
// Set frag pointers to correspond to parity
for (i = k2; i < m2; i++)
frag_ptrs[i] = parity_ptrs[i - k2];
// Set frag pointers to correspond to parity
for (i = k2; i < m2; i++)
frag_ptrs[i] = parity_ptrs[i - k2];
print_list(nerrs2, frag_err_list, " frag err list");
print_list(nerrs2, frag_err_list, " frag err list");
// Find a decode matrix to regenerate all erasures from remaining frags
ret = gf_gen_decode_matrix(encode_matrix, decode_matrix,
invert_matrix, temp_matrix, decode_index, frag_err_list,
nerrs2, k2, m2);
// Find a decode matrix to regenerate all erasures from remaining frags
ret = gf_gen_decode_matrix(encode_matrix, decode_matrix, invert_matrix, temp_matrix,
decode_index, frag_err_list, nerrs2, k2, m2);
if (ret != 0) {
printf("Fail on generate decode matrix\n");
return -1;
}
// Pack recovery array pointers as list of valid fragments
for (i = 0; i < k2; i++)
if (decode_index[i] < k2)
recover_srcs[i] = frag_ptrs[decode_index[i]];
else
recover_srcs[i] = parity_ptrs[decode_index[i] - k2];
if (ret != 0) {
printf("Fail on generate decode matrix\n");
return -1;
}
// Pack recovery array pointers as list of valid fragments
for (i = 0; i < k2; i++)
if (decode_index[i] < k2)
recover_srcs[i] = frag_ptrs[decode_index[i]];
else
recover_srcs[i] = parity_ptrs[decode_index[i] - k2];
print_list(k2, decode_index, " decode index");
print_list(k2, decode_index, " decode index");
// Recover data
ec_init_tables(k2, nerrs2, decode_matrix, g_tbls);
ec_encode_data(len / 2, k2, nerrs2, g_tbls, recover_srcs, recover_outp);
// Recover data
ec_init_tables(k2, nerrs2, decode_matrix, g_tbls);
ec_encode_data(len / 2, k2, nerrs2, g_tbls, recover_srcs, recover_outp);
if (benchmark) {
struct perf start;
BENCHMARK(&start, BENCHMARK_TIME,
ec_encode_data(len / 2, k2, nerrs2, g_tbls, recover_srcs,
recover_outp));
printf("ec_piggyback_decode: ");
perf_print(start, (k2 + nerrs2) * len / 2);
}
// Check that recovered buffers are the same as original
printf(" check recovery of block {");
for (i = 0; i < nerrs2; i++) {
printf(" %d", frag_err_list[i]);
if (memcmp(recover_outp[i], frag_ptrs[frag_err_list[i]], len / 2)) {
printf(" Fail erasure recovery %d, frag %d\n", i, frag_err_list[i]);
return -1;
}
}
printf(" } done all: Pass\n");
if (benchmark) {
struct perf start;
BENCHMARK(&start, BENCHMARK_TIME,
ec_encode_data(len / 2, k2, nerrs2, g_tbls, recover_srcs, recover_outp));
printf("ec_piggyback_decode: ");
perf_print(start, (k2 + nerrs2) * len / 2);
}
// Check that recovered buffers are the same as original
printf(" check recovery of block {");
for (i = 0; i < nerrs2; i++) {
printf(" %d", frag_err_list[i]);
if (memcmp(recover_outp[i], frag_ptrs[frag_err_list[i]], len / 2)) {
printf(" Fail erasure recovery %d, frag %d\n", i, frag_err_list[i]);
return -1;
}
}
printf(" } done all: Pass\n");
return 0;
return 0;
}
// Generate decode matrix from encode matrix and erasure list
static int gf_gen_decode_matrix(u8 * encode_matrix,
u8 * decode_matrix,
u8 * invert_matrix,
u8 * temp_matrix,
u8 * decode_index, u8 * frag_err_list, int nerrs, int k, int m)
static int
gf_gen_decode_matrix(u8 *encode_matrix, u8 *decode_matrix, u8 *invert_matrix, u8 *temp_matrix,
u8 *decode_index, u8 *frag_err_list, int nerrs, int k, int m)
{
int i, j, p, r;
int nsrcerrs = 0;
u8 s, *b = temp_matrix;
u8 frag_in_err[MMAX];
int i, j, p, r;
int nsrcerrs = 0;
u8 s, *b = temp_matrix;
u8 frag_in_err[MMAX];
memset(frag_in_err, 0, sizeof(frag_in_err));
memset(frag_in_err, 0, sizeof(frag_in_err));
// Order the fragments in erasure for easier sorting
for (i = 0; i < nerrs; i++) {
if (frag_err_list[i] < k)
nsrcerrs++;
frag_in_err[frag_err_list[i]] = 1;
}
// Order the fragments in erasure for easier sorting
for (i = 0; i < nerrs; i++) {
if (frag_err_list[i] < k)
nsrcerrs++;
frag_in_err[frag_err_list[i]] = 1;
}
// Construct b (matrix that encoded remaining frags) by removing erased rows
for (i = 0, r = 0; i < k; i++, r++) {
while (frag_in_err[r])
r++;
for (j = 0; j < k; j++)
b[k * i + j] = encode_matrix[k * r + j];
decode_index[i] = r;
}
if (verbose > 1)
print_matrix(k, k, b, "matrix to invert");
// Construct b (matrix that encoded remaining frags) by removing erased rows
for (i = 0, r = 0; i < k; i++, r++) {
while (frag_in_err[r])
r++;
for (j = 0; j < k; j++)
b[k * i + j] = encode_matrix[k * r + j];
decode_index[i] = r;
}
if (verbose > 1)
print_matrix(k, k, b, "matrix to invert");
// Invert matrix to get recovery matrix
if (gf_invert_matrix(b, invert_matrix, k) < 0)
return -1;
// Invert matrix to get recovery matrix
if (gf_invert_matrix(b, invert_matrix, k) < 0)
return -1;
if (verbose > 2)
print_matrix(k, k, invert_matrix, "matrix inverted");
if (verbose > 2)
print_matrix(k, k, invert_matrix, "matrix inverted");
// Get decode matrix with only wanted recovery rows
for (i = 0; i < nsrcerrs; i++) {
for (j = 0; j < k; j++) {
decode_matrix[k * i + j] = invert_matrix[k * frag_err_list[i] + j];
}
}
// Get decode matrix with only wanted recovery rows
for (i = 0; i < nsrcerrs; i++) {
for (j = 0; j < k; j++) {
decode_matrix[k * i + j] = invert_matrix[k * frag_err_list[i] + j];
}
}
// For non-src (parity) erasures need to multiply encode matrix * invert
for (p = nsrcerrs; p < nerrs; p++) {
for (i = 0; i < k; i++) {
s = 0;
for (j = 0; j < k; j++)
s ^= gf_mul(invert_matrix[j * k + i],
encode_matrix[k * frag_err_list[p] + j]);
// For non-src (parity) erasures need to multiply encode matrix * invert
for (p = nsrcerrs; p < nerrs; p++) {
for (i = 0; i < k; i++) {
s = 0;
for (j = 0; j < k; j++)
s ^= gf_mul(invert_matrix[j * k + i],
encode_matrix[k * frag_err_list[p] + j]);
decode_matrix[k * p + i] = s;
}
}
if (verbose > 1)
print_matrix(nerrs, k, decode_matrix, "decode matrix");
return 0;
decode_matrix[k * p + i] = s;
}
}
if (verbose > 1)
print_matrix(nerrs, k, decode_matrix, "decode matrix");
return 0;
}