[SCSI] qla2xxx: Reduce lock-contention during do-work processing.
Queued work processing will now be serialized with its own
lower-priority spinlock. This also simplifies the work-queue
interface for future work-queue consumers.
Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index 128b3d5..dcf0116 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -2533,6 +2533,8 @@
INIT_LIST_HEAD(&vha->work_list);
INIT_LIST_HEAD(&vha->list);
+ spin_lock_init(&vha->work_lock);
+
sprintf(vha->host_str, "%s_%ld", QLA2XXX_DRIVER_NAME, vha->host_no);
return vha;
@@ -2541,13 +2543,11 @@
}
static struct qla_work_evt *
-qla2x00_alloc_work(struct scsi_qla_host *vha, enum qla_work_type type,
- int locked)
+qla2x00_alloc_work(struct scsi_qla_host *vha, enum qla_work_type type)
{
struct qla_work_evt *e;
- e = kzalloc(sizeof(struct qla_work_evt), locked ? GFP_ATOMIC:
- GFP_KERNEL);
+ e = kzalloc(sizeof(struct qla_work_evt), GFP_ATOMIC);
if (!e)
return NULL;
@@ -2558,17 +2558,15 @@
}
static int
-qla2x00_post_work(struct scsi_qla_host *vha, struct qla_work_evt *e, int locked)
+qla2x00_post_work(struct scsi_qla_host *vha, struct qla_work_evt *e)
{
- unsigned long uninitialized_var(flags);
- struct qla_hw_data *ha = vha->hw;
+ unsigned long flags;
- if (!locked)
- spin_lock_irqsave(&ha->hardware_lock, flags);
+ spin_lock_irqsave(&vha->work_lock, flags);
list_add_tail(&e->list, &vha->work_list);
+ spin_unlock_irqrestore(&vha->work_lock, flags);
qla2xxx_wake_dpc(vha);
- if (!locked)
- spin_unlock_irqrestore(&ha->hardware_lock, flags);
+
return QLA_SUCCESS;
}
@@ -2578,13 +2576,13 @@
{
struct qla_work_evt *e;
- e = qla2x00_alloc_work(vha, QLA_EVT_AEN, 1);
+ e = qla2x00_alloc_work(vha, QLA_EVT_AEN);
if (!e)
return QLA_FUNCTION_FAILED;
e->u.aen.code = code;
e->u.aen.data = data;
- return qla2x00_post_work(vha, e, 1);
+ return qla2x00_post_work(vha, e);
}
int
@@ -2592,25 +2590,27 @@
{
struct qla_work_evt *e;
- e = qla2x00_alloc_work(vha, QLA_EVT_IDC_ACK, 1);
+ e = qla2x00_alloc_work(vha, QLA_EVT_IDC_ACK);
if (!e)
return QLA_FUNCTION_FAILED;
memcpy(e->u.idc_ack.mb, mb, QLA_IDC_ACK_REGS * sizeof(uint16_t));
- return qla2x00_post_work(vha, e, 1);
+ return qla2x00_post_work(vha, e);
}
static void
qla2x00_do_work(struct scsi_qla_host *vha)
{
- struct qla_work_evt *e;
- struct qla_hw_data *ha = vha->hw;
+ struct qla_work_evt *e, *tmp;
+ unsigned long flags;
+ LIST_HEAD(work);
- spin_lock_irq(&ha->hardware_lock);
- while (!list_empty(&vha->work_list)) {
- e = list_entry(vha->work_list.next, struct qla_work_evt, list);
+ spin_lock_irqsave(&vha->work_lock, flags);
+ list_splice_init(&vha->work_list, &work);
+ spin_unlock_irqrestore(&vha->work_lock, flags);
+
+ list_for_each_entry_safe(e, tmp, &work, list) {
list_del_init(&e->list);
- spin_unlock_irq(&ha->hardware_lock);
switch (e->type) {
case QLA_EVT_AEN:
@@ -2623,10 +2623,9 @@
}
if (e->flags & QLA_EVT_FLAG_FREE)
kfree(e);
- spin_lock_irq(&ha->hardware_lock);
}
- spin_unlock_irq(&ha->hardware_lock);
}
+
/* Relogins all the fcports of a vport
* Context: dpc thread
*/