On 2/4/21 5:23 PM, Chaitanya Kulkarni wrote:
On 2/4/21 03:40, Mike Christie wrote:
This patch adds plug/unplug callouts for iblock. For initiator drivers
like iscsi which wants to pass multiple cmds to its xmit thread instead
of one cmd at a time, this increases IOPs by around 10% with vhost-scsi
(combined with the last patches we can see a total 40-50% increase). For
driver combos like tcm_loop and faster drivers like the iser initiator, we
can still see IOPs increase by 20-30% when tcm_loop's nr_hw_queues setting
is also increased.
Signed-off-by: Mike Christie <michael.christie@xxxxxxxxxx>
---
drivers/target/target_core_iblock.c | 41 ++++++++++++++++++++++++++++-
drivers/target/target_core_iblock.h | 10 +++++++
2 files changed, 50 insertions(+), 1 deletion(-)
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 8ed93fd205c7..a4951e662615 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -61,9 +61,18 @@ static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *nam
return NULL;
}
+ ib_dev->ibd_plug = kcalloc(nr_cpu_ids, sizeof(*ib_dev->ibd_plug),
+ GFP_KERNEL);
+ if (!ib_dev->ibd_plug)
+ goto free_dev;
+
pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);
return &ib_dev->dev;
+
+free_dev:
+ kfree(ib_dev);
+ return NULL;
}
static int iblock_configure_device(struct se_device *dev)
@@ -171,6 +180,7 @@ static void iblock_dev_call_rcu(struct rcu_head *p)
struct se_device *dev = container_of(p, struct se_device, rcu_head);
struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ kfree(ib_dev->ibd_plug);
kfree(ib_dev);
}
@@ -188,6 +198,30 @@ static void iblock_destroy_device(struct se_device *dev)
bioset_exit(&ib_dev->ibd_bio_set);
}
+static struct se_dev_plug *iblock_plug_device(struct se_cmd *se_cmd)
+{
+ struct se_device *se_dev = se_cmd->se_dev;
+ struct iblock_dev *ib_dev = IBLOCK_DEV(se_dev);
+ struct iblock_dev_plug *ib_dev_plug;
+
+ ib_dev_plug = &ib_dev->ibd_plug[se_cmd->cpuid];
+ if (test_and_set_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags))
+ return NULL;
+
+ blk_start_plug(&ib_dev_plug->blk_plug);
+ return &ib_dev_plug->se_plug;
+}
+
+static void iblock_unplug_device(struct se_dev_plug *se_plug)
+{
+ struct iblock_dev_plug *ib_dev_plug =
+ container_of(se_plug, struct iblock_dev_plug,
+ se_plug);
I think something like on the new line read much easier for me atleast :-
ib_dev_plug = container_of(se_plug, struct iblock_dev_plug,
se_plug);
Yeah nicer. Will change this and the other one.
