From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
This patch changes vhost/scsi to use transport_init_session_tagpool()
pre-allocation logic for per-cpu session tag pooling with internal
tag_alloc() + tag_free() calls based upon the saved se_cmd->map_tag id.
FIXME: Make transport_init_session_tagpool() number of tags
configurable per vring client setting
Cc: Kent Overstreet <koverstreet@xxxxxxxxxx>
Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
Cc: Asias He <asias@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Roland Dreier <roland@xxxxxxxxxx>
Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
---
drivers/vhost/scsi.c | 31 +++++++++++++++++++------------
1 files changed, 19 insertions(+), 12 deletions(-)
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 1e5e820..0f33451 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -48,6 +48,7 @@
#include <linux/virtio_scsi.h>
#include <linux/llist.h>
#include <linux/bitmap.h>
+#include <linux/tags.h>
#include "vhost.c"
#include "vhost.h"
@@ -448,6 +449,7 @@ static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
{
struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
struct tcm_vhost_cmd, tvc_se_cmd);
+ struct se_session *se_sess = se_cmd->se_sess;
if (tv_cmd->tvc_sgl_count) {
u32 i;
@@ -458,7 +460,7 @@ static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
}
tcm_vhost_put_inflight(tv_cmd->inflight);
- kfree(tv_cmd);
+ tag_free(&se_sess->sess_tag_pool, se_cmd->map_tag);
}
static int tcm_vhost_shutdown_session(struct se_session *se_sess)
@@ -700,7 +702,7 @@ static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
vhost_signal(&vs->dev, &vs->vqs[vq].vq);
}
-static struct tcm_vhost_cmd *vhost_scsi_allocate_cmd(
+static struct tcm_vhost_cmd *vhost_scsi_get_tag(
struct vhost_virtqueue *vq,
struct tcm_vhost_tpg *tv_tpg,
struct virtio_scsi_cmd_req *v_req,
@@ -709,18 +711,21 @@ static struct tcm_vhost_cmd *vhost_scsi_allocate_cmd(
{
struct tcm_vhost_cmd *tv_cmd;
struct tcm_vhost_nexus *tv_nexus;
+ struct se_session *se_sess;
+ int tag;
tv_nexus = tv_tpg->tpg_nexus;
if (!tv_nexus) {
pr_err("Unable to locate active struct tcm_vhost_nexus\n");
return ERR_PTR(-EIO);
}
+ se_sess = tv_nexus->tvn_se_sess;
- tv_cmd = kzalloc(sizeof(struct tcm_vhost_cmd), GFP_ATOMIC);
- if (!tv_cmd) {
- pr_err("Unable to allocate struct tcm_vhost_cmd\n");
- return ERR_PTR(-ENOMEM);
- }
+ tag = tag_alloc(&se_sess->sess_tag_pool, true);
+ tv_cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[tag];
+ memset(tv_cmd, 0, sizeof(struct tcm_vhost_cmd));
+
+ tv_cmd->tvc_se_cmd.map_tag = tag;
tv_cmd->tvc_tag = v_req->tag;
tv_cmd->tvc_task_attr = v_req->task_attr;
tv_cmd->tvc_exp_data_len = exp_data_len;
@@ -982,10 +987,10 @@ static void vhost_scsi_handle_vq(struct vhost_scsi *vs,
for (i = 0; i < data_num; i++)
exp_data_len += vq->iov[data_first + i].iov_len;
- tv_cmd = vhost_scsi_allocate_cmd(vq, tv_tpg, &v_req,
- exp_data_len, data_direction);
+ tv_cmd = vhost_scsi_get_tag(vq, tv_tpg, &v_req,
+ exp_data_len, data_direction);
if (IS_ERR(tv_cmd)) {
- vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n",
+ vq_err(vq, "vhost_scsi_get_tag failed %ld\n",
PTR_ERR(tv_cmd));
goto err_cmd;
}
@@ -1662,9 +1667,11 @@ static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tv_tpg,
return -ENOMEM;
}
/*
- * Initialize the struct se_session pointer
+ * Initialize the struct se_session pointer and setup tagpool
+ * for struct tcm_vhost_cmd descriptors
*/
- tv_nexus->tvn_se_sess = transport_init_session();
+ tv_nexus->tvn_se_sess = transport_init_session_tagpool(256,
+ sizeof(struct tcm_vhost_cmd));
if (IS_ERR(tv_nexus->tvn_se_sess)) {
mutex_unlock(&tv_tpg->tv_tpg_mutex);
kfree(tv_nexus);
--
1.7.2.5
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
