1#include <fcntl.h>
2#include "perf_index.h"
3#include <errno.h>
4
5#define MAXFILESIZE 8589934592L
6
7static int *fds = NULL;
8static char writebuff[4096];
9
10void stress_file_write_init(const char *fs_path, int num_threads, long long length) {
11  int i;
12  char filepath[MAXPATHLEN];
13
14  if(fds == NULL)
15    fds = (int*)malloc(sizeof(int)*num_threads);
16  for(i=0; i<num_threads; i++) {
17    snprintf(filepath, sizeof(filepath), "%s/file_write-%d", fs_path, i);
18    fds[i] = open(filepath, O_CREAT | O_EXCL | O_WRONLY, 0644);
19    assert(fds[i] > 0);
20  }
21  bzero(writebuff, sizeof(writebuff));
22}
23
24void stress_file_write(const char *fs_path, int thread_id, int num_threads, long long length, long long max_file_size) {
25  long long left;
26  size_t file_offset = 0;
27  int writelen;
28  char filepath[MAXPATHLEN];
29  int fd = fds[thread_id];
30
31  if(max_file_size == 0)
32    max_file_size = MAXFILESIZE;
33
34  for(left=length; left>0;) {
35    writelen = sizeof(writebuff) < left ? sizeof(writebuff) : left;
36    assert(write(fd, writebuff, writelen) == writelen);
37    left -= writelen;
38    file_offset += writelen;
39    if(file_offset>max_file_size/num_threads) {
40      lseek(fd, 0, SEEK_SET);
41      file_offset = 0;
42    }
43  }
44  snprintf(filepath, sizeof(filepath), "%s/file_write-%d", fs_path, thread_id);
45  assert(unlink(filepath)>=0);
46}
47