From fad82f76eaa03e2f486315537e9d83809d155d58 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 19 Sep 2011 11:33:30 +0200 Subject: [PATCH] Scramble fix Signed-off-by: Jens Axboe --- io_u.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/io_u.c b/io_u.c index 5959bf7f..38efcc16 100644 --- a/io_u.c +++ b/io_u.c @@ -1129,6 +1129,7 @@ static int check_get_verify(struct thread_data *td, struct io_u *io_u) static void small_content_scramble(struct io_u *io_u) { unsigned int i, nr_blocks = io_u->buflen / 512; + unsigned long long boffset; unsigned int offset; void *p, *end; @@ -1136,20 +1137,23 @@ static void small_content_scramble(struct io_u *io_u) return; p = io_u->xfer_buf; + boffset= io_u->offset; + for (i = 0; i < nr_blocks; i++) { /* * Fill the byte offset into a "random" start offset of * the buffer, given by the product of the usec time * and the actual offset. */ - offset = (io_u->start_time.tv_usec * io_u->offset) & 511; + offset = (io_u->start_time.tv_usec ^ boffset) & 511; if (offset >= 512 - sizeof(unsigned long long)) offset -= sizeof(unsigned long long); - *((unsigned long long *) p + offset) = io_u->offset; + *((unsigned long long *) p + offset) = boffset; end = p + 512 - sizeof(io_u->start_time); memcpy(end, &io_u->start_time, sizeof(io_u->start_time)); p += 512; + boffset += 512; } } -- 2.25.1