Speed up verify fill

It's silly to fill an on-stack header, and then copy it to the io_u.
Just map the pointer to the buffer start.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/verify.c b/verify.c
index 533c6acf6361ee89ab93450f04a6bc7967987be7..6c703eef73c3fa6911e6bc1ffc5de3923d0fe442 100644 (file)
--- a/verify.c
+++ b/verify.c
@@ -174,32 +174,38 @@ static void fill_md5(struct verify_header *hdr, void *p, unsigned int len)
  */
 void populate_verify_io_u(struct thread_data *td, struct io_u *io_u)
 {
-       unsigned char *p = (unsigned char *) io_u->buf;
-       struct verify_header hdr;
+       const unsigned int len = io_u->buflen - sizeof(struct verify_header);
+       struct verify_header *hdr;
+       unsigned char *p;
 
        if (td->o.verify == VERIFY_NULL)
                return;
 
-       hdr.fio_magic = FIO_HDR_MAGIC;
-       hdr.len = io_u->buflen;
-       p += sizeof(hdr);
-       fill_random_bytes(td, p, io_u->buflen - sizeof(hdr));
-
-       if (td->o.verify == VERIFY_MD5) {
-               fill_md5(&hdr, p, io_u->buflen - sizeof(hdr));
-               hdr.verify_type = VERIFY_MD5;
-       } else if (td->o.verify == VERIFY_CRC32) {
-               fill_crc32(&hdr, p, io_u->buflen - sizeof(hdr));
-               hdr.verify_type = VERIFY_CRC32;
-       } else if (td->o.verify == VERIFY_CRC16) {
-               fill_crc16(&hdr, p, io_u->buflen - sizeof(hdr));
-               hdr.verify_type = VERIFY_CRC16;
-       } else if (td->o.verify == VERIFY_CRC7) {
-               fill_crc7(&hdr, p, io_u->buflen - sizeof(hdr));
-               hdr.verify_type = VERIFY_CRC7;
+       hdr = (struct verify_header *) io_u->buf;
+       hdr->fio_magic = FIO_HDR_MAGIC;
+       hdr->len = io_u->buflen;
+       hdr->verify_type = td->o.verify;
+
+       p = io_u->buf + sizeof(*hdr);
+       fill_random_bytes(td, p, len);
+
+       switch (td->o.verify) {
+       case VERIFY_MD5:
+               fill_md5(hdr, p, len);
+               break;
+       case VERIFY_CRC32:
+               fill_crc32(hdr, p, len);
+               break;
+       case VERIFY_CRC16:
+               fill_crc16(hdr, p, len);
+               break;
+       case VERIFY_CRC7:
+               fill_crc7(hdr, p, len);
+               break;
+       default:
+               log_err("fio: bad verify type: %d\n", td->o.verify);
+               assert(0);
        }
-
-       memcpy(io_u->buf, &hdr, sizeof(hdr));
 }
 
 int get_next_verify(struct thread_data *td, struct io_u *io_u)