X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;ds=sidebyside;f=io_u.c;h=0bc83d2277633c8057c81c53a84e6685547af840;hb=5efce23f88563bc08f64e122297fcfbea32fdd4f;hp=7709df5fe55bf7fb6237d6b93476b2f09a2d3d3d;hpb=78c1eda5486f586ca73e9cbe7e40b93fccdbd218;p=fio.git

diff --git a/io_u.c b/io_u.c
index 7709df5f..0bc83d22 100644
--- a/io_u.c
+++ b/io_u.c
@@ -13,6 +13,7 @@
 
 struct io_completion_data {
 	int nr;				/* input */
+	int account;			/* input */
 
 	int error;			/* output */
 	unsigned long bytes_done[2];	/* output */
@@ -249,8 +250,12 @@ static int get_next_seq_block(struct thread_data *td, struct fio_file *f,
 	assert(ddir_rw(ddir));
 
 	if (f->last_pos < f->real_file_size) {
-		unsigned long long pos = f->last_pos - f->file_offset;
+		unsigned long long pos;
 
+		if (f->last_pos == f->file_offset && td->o.ddir_seq_add < 0)
+			f->last_pos = f->real_file_size;
+
+		pos = f->last_pos - f->file_offset;
 		if (pos)
 			pos += td->o.ddir_seq_add;
 
@@ -1116,6 +1121,44 @@ static int check_get_verify(struct thread_data *td, struct io_u *io_u)
 	return 0;
 }
 
+/*
+ * Fill offset and start time into the buffer content, to prevent too
+ * easy compressible data for simple de-dupe attempts. Do this for every
+ * 512b block in the range, since that should be the smallest block size
+ * we can expect from a device.
+ */
+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;
+
+	if (!nr_blocks)
+		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 ^ boffset) & 511;
+		offset &= ~(sizeof(unsigned long long) - 1);
+		if (offset >= 512 - sizeof(unsigned long long))
+			offset -= sizeof(unsigned long long);
+		memcpy(p + offset, &boffset, sizeof(boffset));
+
+		end = p + 512 - sizeof(io_u->start_time);
+		memcpy(end, &io_u->start_time, sizeof(io_u->start_time));
+		p += 512;
+		boffset += 512;
+	}
+}
+
 /*
  * Return an io_u to be processed. Gets a buflen and offset, sets direction,
  * etc. The returned io_u is fully ready to be prepped and submitted.
@@ -1124,6 +1167,7 @@ struct io_u *get_io_u(struct thread_data *td)
 {
 	struct fio_file *f;
 	struct io_u *io_u;
+	int do_scramble = 0;
 
 	io_u = __get_io_u(td);
 	if (!io_u) {
@@ -1165,11 +1209,14 @@ struct io_u *get_io_u(struct thread_data *td)
 		f->last_start = io_u->offset;
 		f->last_pos = io_u->offset + io_u->buflen;
 
-		if (td->o.verify != VERIFY_NONE && io_u->ddir == DDIR_WRITE)
-			populate_verify_io_u(td, io_u);
-		else if (td->o.refill_buffers && io_u->ddir == DDIR_WRITE)
-			io_u_fill_buffer(td, io_u, io_u->xfer_buflen);
-		else if (io_u->ddir == DDIR_READ) {
+		if (io_u->ddir == DDIR_WRITE) {
+			if (td->o.verify != VERIFY_NONE)
+				populate_verify_io_u(td, io_u);
+			else if (td->o.refill_buffers)
+				io_u_fill_buffer(td, io_u, io_u->xfer_buflen);
+			else if (td->o.scramble_buffers)
+				do_scramble = 1;
+		} else if (io_u->ddir == DDIR_READ) {
 			/*
 			 * Reset the buf_filled parameters so next time if the
 			 * buffer is used for writes it is refilled.
@@ -1189,6 +1236,8 @@ out:
 	if (!td_io_prep(td, io_u)) {
 		if (!td->o.disable_slat)
 			fio_gettime(&io_u->start_time, NULL);
+		if (do_scramble)
+			small_content_scramble(io_u);
 		return io_u;
 	}
 err_put:
@@ -1218,6 +1267,34 @@ void io_u_log_error(struct thread_data *td, struct io_u *io_u)
 		td_verror(td, io_u->error, "io_u error");
 }
 
+static void account_io_completion(struct thread_data *td, struct io_u *io_u,
+				  struct io_completion_data *icd,
+				  const enum fio_ddir idx, unsigned int bytes)
+{
+	unsigned long uninitialized_var(lusec);
+
+	if (!icd->account)
+		return;
+
+	if (!td->o.disable_clat || !td->o.disable_bw)
+		lusec = utime_since(&io_u->issue_time, &icd->time);
+
+	if (!td->o.disable_lat) {
+		unsigned long tusec;
+
+		tusec = utime_since(&io_u->start_time, &icd->time);
+		add_lat_sample(td, idx, tusec, bytes);
+	}
+
+	if (!td->o.disable_clat) {
+		add_clat_sample(td, idx, lusec, bytes);
+		io_u_mark_latency(td, lusec);
+	}
+
+	if (!td->o.disable_bw)
+		add_bw_sample(td, idx, bytes, &icd->time);
+}
+
 static void io_completed(struct thread_data *td, struct io_u *io_u,
 			 struct io_completion_data *icd)
 {
@@ -1271,24 +1348,8 @@ static void io_completed(struct thread_data *td, struct io_u *io_u,
 		}
 
 		if (ramp_time_over(td)) {
-			unsigned long uninitialized_var(lusec);
-
-			if (!td->o.disable_clat || !td->o.disable_bw)
-				lusec = utime_since(&io_u->issue_time,
-							&icd->time);
-			if (!td->o.disable_lat) {
-				unsigned long tusec;
+			account_io_completion(td, io_u, icd, idx, bytes);
 
-				tusec = utime_since(&io_u->start_time,
-							&icd->time);
-				add_lat_sample(td, idx, tusec, bytes);
-			}
-			if (!td->o.disable_clat) {
-				add_clat_sample(td, idx, lusec, bytes);
-				io_u_mark_latency(td, lusec);
-			}
-			if (!td->o.disable_bw)
-				add_bw_sample(td, idx, bytes, &icd->time);
 			if (__should_check_rate(td, idx)) {
 				td->rate_pending_usleep[idx] =
 					((td->this_io_bytes[idx] *
@@ -1338,6 +1399,7 @@ static void init_icd(struct thread_data *td, struct io_completion_data *icd,
 		fio_gettime(&icd->time, NULL);
 
 	icd->nr = nr;
+	icd->account = 1;
 
 	icd->error = 0;
 	icd->bytes_done[0] = icd->bytes_done[1] = 0;
@@ -1356,6 +1418,8 @@ static void ios_completed(struct thread_data *td,
 
 		if (!(io_u->flags & IO_U_F_FREE_DEF))
 			put_io_u(td, io_u);
+
+		icd->account = 0;
 	}
 }
 
@@ -1446,7 +1510,7 @@ void io_u_fill_buffer(struct thread_data *td, struct io_u *io_u,
 	io_u->buf_filled_len = 0;
 
 	if (!td->o.zero_buffers)
-		fill_random_buf(io_u->buf, max_bs);
+		fill_random_buf(&td->buf_state, io_u->buf, max_bs);
 	else
 		memset(io_u->buf, 0, max_bs);
 }