This patch refactors the busy checking codes of scsi_device,
Scsi_Host and scsi_target. There should be no functional change.
This is a preparation for another patch which exports scsi's busy
state to the block layer for request stacking drivers.
Signed-off-by: Kiyoshi Ueda <k-ueda@xxxxxxxxxxxxx>
Signed-off-by: Jun'ichi Nomura <j-nomura@xxxxxxxxxxxxx>
Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/scsi/scsi_lib.c | 30 ++++++++++++++++++++----------
1 files changed, 20 insertions(+), 10 deletions(-)
Index: scsi-post-merge-2.6/drivers/scsi/scsi_lib.c
===================================================================
--- scsi-post-merge-2.6.orig/drivers/scsi/scsi_lib.c
+++ scsi-post-merge-2.6/drivers/scsi/scsi_lib.c
@@ -529,6 +529,14 @@ static void scsi_single_lun_run(struct s
spin_unlock_irqrestore(shost->host_lock, flags);
}
+static inline int scsi_device_is_busy(struct scsi_device *sdev)
+{
+ if (sdev->device_busy >= sdev->queue_depth || sdev->device_blocked)
+ return 1;
+
+ return 0;
+}
+
static inline int scsi_target_is_busy(struct scsi_target *starget)
{
return ((starget->can_queue > 0 &&
@@ -536,6 +544,15 @@ static inline int scsi_target_is_busy(st
starget->target_blocked);
}
+static inline int scsi_host_is_busy(struct Scsi_Host *shost)
+{
+ if ((shost->can_queue > 0 && shost->host_busy >= shost->can_queue) ||
+ shost->host_blocked || shost->host_self_blocked)
+ return 1;
+
+ return 0;
+}
+
/*
* Function: scsi_run_queue()
*
@@ -558,11 +575,7 @@ static void scsi_run_queue(struct reques
scsi_single_lun_run(sdev);
spin_lock_irqsave(shost->host_lock, flags);
- while (!list_empty(&shost->starved_list) &&
- !shost->host_blocked && !shost->host_self_blocked &&
- !((shost->can_queue > 0) &&
- (shost->host_busy >= shost->can_queue))) {
-
+ while (!list_empty(&shost->starved_list) && !scsi_host_is_busy(shost)) {
int flagset;
/*
@@ -1348,8 +1361,6 @@ int scsi_prep_fn(struct request_queue *q
static inline int scsi_dev_queue_ready(struct request_queue *q,
struct scsi_device *sdev)
{
- if (sdev->device_busy >= sdev->queue_depth)
- return 0;
if (sdev->device_busy == 0 && sdev->device_blocked) {
/*
* unblock after device_blocked iterates to zero
@@ -1363,7 +1374,7 @@ static inline int scsi_dev_queue_ready(s
return 0;
}
}
- if (sdev->device_blocked)
+ if (scsi_device_is_busy(sdev))
return 0;
return 1;
@@ -1440,8 +1451,7 @@ static inline int scsi_host_queue_ready(
return 0;
}
}
- if ((shost->can_queue > 0 && shost->host_busy >= shost->can_queue) ||
- shost->host_blocked || shost->host_self_blocked) {
+ if (scsi_host_is_busy(shost)) {
if (list_empty(&sdev->starved_entry))
list_add_tail(&sdev->starved_entry, &shost->starved_list);
return 0;
--
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