static void store_pageinfo(int fd)
{
int i;
sigset_t mask, old_mask;
sigfillset(&mask);
sigprocmask(SIG_BLOCK, &mask, &old_mask);
/* Hint we'll be using this file only once;
* the Linux kernel will currently ignore this */
fadv_noreuse(fd, 0, 0);
/* check if there's space to store the info */
pthread_mutex_lock(&lock);
for(i = 0; i < max_fds && fds[i].fd != -1; i++)
;
if(i == max_fds) {
pthread_mutex_unlock(&lock);
goto restoresigset; /* no space! */
}
fds[i].fd = fd;
pthread_mutex_unlock(&lock);
if(!fd_get_pageinfo(fd, &fds[i]))
goto cleanup;
DEBUG("store_pageinfo(fd=%d): pages in cache: %zd/%zd (%.1f%%) [filesize=%.1fK, "
"pagesize=%dK]\n", fd, fds[i].nr_pages_cached, fds[i].nr_pages,
fds[i].nr_pages == 0 ? 0 : (100.0 * fds[i].nr_pages_cached / fds[i].nr_pages),
1.0 * fds[i].size / 1024, (int) PAGESIZE / 1024);
goto restoresigset;
cleanup:
fds[i].fd = -1;
restoresigset:
sigprocmask(SIG_SETMASK, &old_mask, NULL);
return;
}
static void store_pageinfo(int fd)
{
int i;
int pages;
struct stat st;
void *file = NULL;
unsigned char *pageinfo = NULL;
sigset_t mask, old_mask;
sigfillset(&mask);
sigprocmask(SIG_BLOCK, &mask, &old_mask);
if(fstat(fd, &st) == -1 || !S_ISREG(st.st_mode))
goto restoresigset;
/* Hint we'll be using this file only once;
* the Linux kernel will currently ignore this */
fadv_noreuse(fd, 0, 0);
/* check if there's space to store the info */
pthread_mutex_lock(&lock);
for(i = 0; i < max_fds && fds[i].fd != -1; i++)
;
if(i == max_fds) {
pthread_mutex_unlock(&lock);
goto restoresigset; /* no space! */
}
fds[i].fd = fd;
pthread_mutex_unlock(&lock);
/* If size is 0, mmap() will fail. We'll keep the fd stored, anyway, to
* make sure the newly written pages will be freed (so no cleanup!). */
if(st.st_size == 0) {
fds[i].size = 0;
fds[i].nr_pages = 0;
fds[i].info = NULL;
DEBUG("store_pageinfo(fd=%d): file size is ZERO, slot=%d\n", fd, i);
goto restoresigset;
}
DEBUG("store_pageinfo(fd=%d): st.st_size=%ld\n", fd, st.st_size);
fds[i].size = st.st_size;
pages = fds[i].nr_pages = (st.st_size + PAGESIZE - 1) / PAGESIZE;
pageinfo = calloc(sizeof(*pageinfo), pages);
if(!pageinfo) {
DEBUG("calloc failed: size=%d on fd=%d slot=%d\n", pages, fd, i);
goto cleanup;
}
file = mmap(NULL, st.st_size, PROT_NONE, MAP_SHARED, fd, 0);
if(file == MAP_FAILED) {
DEBUG("store_pageinfo(fd=%d): mmap failed, errno:%d, %s\n",
fd, errno, strerror(errno));
goto cleanup;
}
if(mincore(file, st.st_size, pageinfo) == -1)
goto cleanup;
fds[i].info = pageinfo;
munmap(file, st.st_size);
if(debugfp != NULL) {
int j, n = 0;
for(j = 0; j < pages; j++)
if(pageinfo[j] & 1)
n++;
DEBUG("store_pageinfo(fd=%d): pages in cache: %d/%d (%.1f%%) [filesize=%.1fK, "
"pagesize=%dK]\n", fd, n, pages, 100.0 * n / pages,
1.0 * st.st_size / 1024, (int) PAGESIZE / 1024);
}
goto restoresigset;
cleanup:
fds[i].fd = -1;
if(pageinfo)
free(pageinfo);
if(file)
munmap(file, st.st_size);
restoresigset:
sigprocmask(SIG_SETMASK, &old_mask, NULL);
return;
}