From: Jens Axboe <axboe@kernel.dk>
Date: Mon, 24 Sep 2012 12:25:33 +0000 (+0200)
Subject: backend: don't allocate memory buffers for non-data workloads
X-Git-Tag: fio-2.0.10~17
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=59d8d0f5fb939ef23e4aa495dbe8fabd59d5bf25;p=fio.git

backend: don't allocate memory buffers for non-data workloads

A trim workload doesn't transfer any actual data, so don't any
backing memory for the IO buffers.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/backend.c b/backend.c
index 39d13a33..88623bea 100644
--- a/backend.c
+++ b/backend.c
@@ -802,6 +802,7 @@ static int init_io_u(struct thread_data *td)
 	struct io_u *io_u;
 	unsigned int max_bs, min_write;
 	int cl_align, i, max_units;
+	int data_xfer = 1;
 	char *p;
 
 	max_units = td->o.iodepth;
@@ -811,6 +812,9 @@ static int init_io_u(struct thread_data *td)
 	td->orig_buffer_size = (unsigned long long) max_bs
 					* (unsigned long long) max_units;
 
+	if ((td->io_ops->flags & FIO_NOIO) || !td_rw(td))
+		data_xfer = 0;
+
 	if (td->o.mem_type == MEM_SHMHUGE || td->o.mem_type == MEM_MMAPHUGE) {
 		unsigned long bs;
 
@@ -823,7 +827,7 @@ static int init_io_u(struct thread_data *td)
 		return 1;
 	}
 
-	if (allocate_io_mem(td))
+	if (data_xfer && allocate_io_mem(td))
 		return 1;
 
 	if (td->o.odirect || td->o.mem_align ||
@@ -851,7 +855,7 @@ static int init_io_u(struct thread_data *td)
 		INIT_FLIST_HEAD(&io_u->list);
 		dprint(FD_MEM, "io_u alloc %p, index %u\n", io_u, i);
 
-		if (!(td->io_ops->flags & FIO_NOIO)) {
+		if (data_xfer) {
 			io_u->buf = p;
 			dprint(FD_MEM, "io_u %p, mem %p\n", io_u, io_u->buf);