diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2011-02-18 09:25:07 -0800 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2011-07-03 03:55:27 -0700 |
| commit | 0cf89d1d27c1bdd0abf1714096f98ea44704dcff (patch) | |
| tree | 0bee9fa05aba8a6e1fe4b6b50a3bfc6d0793356f /drivers/scsi/isci/host.h | |
| parent | c7ef4031f01301298bbaba2666740183cd399f8c (diff) | |
isci: cleanup "starting" state handling
The lldd actively disallows requests in the "starting" state. Retrying
or holding off commands in this state is sub-optimal:
1/ it adds another state check to the fast path
2/ retrying can cause libsas to give up
However, isci's ->lldd_dev_found() routine already waits for controller
start to complete before allowing further progress. Checking the
"starting" state in isci_task_execute_task and the isr is redundant and
misleading. Clean this up and introduce a controller-wide event queue
to start reeling in "completion" proliferation in the driver.
The "stopping" state cleanups are in a similar vein, rely on the the isr
and other paths being precluded from occurring rather than implementing
state checking logic.
Reported-by: Christoph Hellwig <hch@infradead.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Edmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/scsi/isci/host.h')
| -rw-r--r-- | drivers/scsi/isci/host.h | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/drivers/scsi/isci/host.h b/drivers/scsi/isci/host.h index 421d3debdae..26768c5bbe0 100644 --- a/drivers/scsi/isci/host.h +++ b/drivers/scsi/isci/host.h @@ -109,13 +109,15 @@ struct isci_host { u8 sas_addr[SAS_ADDR_SIZE]; enum isci_status status; + #define IHOST_START_PENDING 0 + #define IHOST_STOP_PENDING 1 + unsigned long flags; + wait_queue_head_t eventq; struct Scsi_Host *shost; struct tasklet_struct completion_tasklet; struct list_head mdl_struct_list; struct list_head requests_to_complete; struct list_head requests_to_abort; - struct completion stop_complete; - struct completion start_complete; spinlock_t scic_lock; struct isci_host *next; }; @@ -202,6 +204,17 @@ static inline void isci_host_can_dequeue( spin_unlock_irqrestore(&isci_host->queue_lock, flags); } +static inline void wait_for_start(struct isci_host *ihost) +{ + wait_event(ihost->eventq, !test_bit(IHOST_START_PENDING, &ihost->flags)); +} + +static inline void wait_for_stop(struct isci_host *ihost) +{ + wait_event(ihost->eventq, !test_bit(IHOST_STOP_PENDING, &ihost->flags)); +} + + /** * isci_host_from_sas_ha() - This accessor retrieves the isci_host object * reference from the Linux sas_ha_struct reference. |