From: Jens Axboe <jens.axboe@oracle.com>
Date: Mon, 30 Oct 2006 16:00:24 +0000 (+0100)
Subject: [PATCH] Randomly fill output buffers
X-Git-Tag: fio-1.8~18
X-Git-Url: https://git.kernel.dk/?p=fio.git;a=commitdiff_plain;h=6b9cea23c22c218625b68eca63da38089b299846

[PATCH] Randomly fill output buffers

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

diff --git a/fio.c b/fio.c
index 81e9e90d..52caa4e9 100644
--- a/fio.c
+++ b/fio.c
@@ -479,6 +479,19 @@ static void cleanup_io_u(struct thread_data *td)
 	free_io_mem(td);
 }
 
+/*
+ * "randomly" fill the buffer contents
+ */
+static void fill_rand_buf(struct io_u *io_u, unsigned int max_bs)
+{
+	unsigned int *ptr = io_u->buf;
+
+	while ((void *) ptr - io_u->buf < max_bs) {
+		*ptr = rand() * 0x9e370001;
+		ptr++;
+	}
+}
+
 static int init_io_u(struct thread_data *td)
 {
 	struct io_u *io_u;
@@ -505,6 +518,9 @@ static int init_io_u(struct thread_data *td)
 		INIT_LIST_HEAD(&io_u->list);
 
 		io_u->buf = p + td->max_bs * i;
+		if (td_write(td) || td_rw(td))
+			fill_rand_buf(io_u, td->max_bs);
+
 		io_u->index = i;
 		list_add(&io_u->list, &td->io_u_freelist);
 	}
diff --git a/fio.h b/fio.h
index b30dec59..6a68ec8d 100644
--- a/fio.h
+++ b/fio.h
@@ -63,7 +63,7 @@ struct io_u {
 	struct timeval start_time;
 	struct timeval issue_time;
 
-	char *buf;
+	void *buf;
 	unsigned int buflen;
 	unsigned long long offset;