We don't need protection against the SCSI stack, so use our own lock to
allow parallel progress on separate CPUs.
This is a break-out of Bart Van Assche's work.
---
drivers/infiniband/ulp/srp/ib_srp.c | 42 +++++++++++++++++-----------------
drivers/infiniband/ulp/srp/ib_srp.h | 2 +
2 files changed, 23 insertions(+), 21 deletions(-)
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c
b/drivers/infiniband/ulp/srp/ib_srp.c
index 4e8ae59..fff72c8 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -447,12 +447,12 @@ static bool srp_change_state(struct srp_target_port
*target,
{
int changed = false;
- spin_lock_irq(target->scsi_host->host_lock);
+ spin_lock_irq(&target->lock);
if (target->state == old) {
target->state = new;
changed = true;
}
- spin_unlock_irq(target->scsi_host->host_lock);
+ spin_unlock_irq(&target->lock);
return changed;
}
@@ -555,11 +555,11 @@ static void srp_remove_req(struct srp_target_port *target,
unsigned long flags;
srp_unmap_data(req->scmnd, target, req);
- spin_lock_irqsave(target->scsi_host->host_lock, flags);
+ spin_lock_irqsave(&target->lock, flags);
target->req_lim += req_lim_delta;
req->scmnd = NULL;
list_move_tail(&req->list, &target->free_reqs);
- spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
+ spin_unlock_irqrestore(&target->lock, flags);
}
static void srp_reset_req(struct srp_target_port *target, struct srp_request
*req)
@@ -634,13 +634,13 @@ err:
* Schedule our work inside the lock to avoid a race with
* the flush_scheduled_work() in srp_remove_one().
*/
- spin_lock_irq(target->scsi_host->host_lock);
+ spin_lock_irq(&target->lock);
if (target->state == SRP_TARGET_CONNECTING) {
target->state = SRP_TARGET_DEAD;
INIT_WORK(&target->work, srp_remove_work);
schedule_work(&target->work);
}
- spin_unlock_irq(target->scsi_host->host_lock);
+ spin_unlock_irq(&target->lock);
return ret;
}
@@ -829,17 +829,16 @@ static void srp_put_tx_iu(struct srp_target_port *target,
struct srp_iu *iu,
{
unsigned long flags;
- spin_lock_irqsave(target->scsi_host->host_lock, flags);
+ spin_lock_irqsave(&target->lock, flags);
list_add(&iu->list, &target->free_tx);
if (iu_type != SRP_IU_RSP)
++target->req_lim;
- spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
+ spin_unlock_irqrestore(&target->lock, flags);
}
/*
- * Must be called with target->scsi_host->host_lock held to protect
- * req_lim and free_tx. If IU is not sent, it must be returned using
- * srp_put_tx_iu().
+ * Must be called with target->lock held to protect req_lim and free_tx.
+ * If IU is not sent, it must be returned using srp_put_tx_iu().
*
* Note:
* An upper limit for the number of allocated information units for each
@@ -958,10 +957,10 @@ static int srp_response_common(struct srp_target_port
*target, s32 req_delta,
struct srp_iu *iu;
int err;
- spin_lock_irqsave(target->scsi_host->host_lock, flags);
+ spin_lock_irqsave(&target->lock, flags);
target->req_lim += req_delta;
iu = __srp_get_tx_iu(target, SRP_IU_RSP);
- spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
+ spin_unlock_irqrestore(&target->lock, flags);
if (!iu) {
shost_printk(KERN_ERR, target->scsi_host, PFX
@@ -1126,7 +1125,7 @@ static int srp_queuecommand(struct Scsi_Host *shost,
struct scsi_cmnd *scmnd)
return 0;
}
- spin_lock_irqsave(shost->host_lock, flags);
+ spin_lock_irqsave(&target->lock, flags);
/* This goes away once the scsi_eh routines stop testing it. */
scsi_cmd_get_serial(shost, scmnd);
iu = __srp_get_tx_iu(target, SRP_IU_CMD);
@@ -1135,7 +1134,7 @@ static int srp_queuecommand(struct Scsi_Host *shost,
struct scsi_cmnd *scmnd)
list);
list_del_init(&req->list);
}
- spin_unlock_irqrestore(shost->host_lock, flags);
+ spin_unlock_irqrestore(&target->lock, flags);
if (!iu)
goto err;
@@ -1181,9 +1180,9 @@ err_unmap:
err_iu:
srp_put_tx_iu(target, iu, SRP_IU_CMD);
- spin_lock_irqsave(shost->host_lock, flags);
+ spin_lock_irqsave(&target->lock, flags);
list_add(&req->list, &target->free_reqs);
- spin_unlock_irqrestore(shost->host_lock, flags);
+ spin_unlock_irqrestore(&target->lock, flags);
err:
return SCSI_MLQUEUE_HOST_BUSY;
@@ -1449,9 +1448,9 @@ static int srp_send_tsk_mgmt(struct srp_target_port
*target,
init_completion(&target->tsk_mgmt_done);
- spin_lock_irq(target->scsi_host->host_lock);
+ spin_lock_irq(&target->lock);
iu = __srp_get_tx_iu(target, SRP_IU_TSK_MGMT);
- spin_unlock_irq(target->scsi_host->host_lock);
+ spin_unlock_irq(&target->lock);
if (!iu)
return -1;
@@ -1955,6 +1954,7 @@ static ssize_t srp_create_target(struct device *dev,
target->scsi_host = target_host;
target->srp_host = host;
+ spin_lock_init(&target->lock);
INIT_LIST_HEAD(&target->free_tx);
INIT_LIST_HEAD(&target->free_reqs);
for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
@@ -2184,9 +2184,9 @@ static void srp_remove_one(struct ib_device *device)
*/
spin_lock(&host->target_lock);
list_for_each_entry(target, &host->target_list, list) {
- spin_lock_irq(target->scsi_host->host_lock);
+ spin_lock_irq(&target->lock);
target->state = SRP_TARGET_REMOVED;
- spin_unlock_irq(target->scsi_host->host_lock);
+ spin_unlock_irq(&target->lock);
}
spin_unlock(&host->target_lock);
diff --git a/drivers/infiniband/ulp/srp/ib_srp.h
b/drivers/infiniband/ulp/srp/ib_srp.h
index e2b1719..c4699ea 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.h
+++ b/drivers/infiniband/ulp/srp/ib_srp.h
@@ -144,6 +144,8 @@ struct srp_target_port {
struct srp_iu *rx_ring[SRP_RQ_SIZE];
+ spinlock_t lock;
+
struct list_head free_tx;
struct srp_iu *tx_ring[SRP_SQ_SIZE];
--
1.7.2.3
--
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