[PATCH 1/2] scsi: smartpqi: Replace semaphore sync_request_sem with mutex

Binoy Jayan
2016-10-20T08:54:19Z

Semaphores are going away in the future, so replace the semaphore
sync_request_sem with the a mutex lock. timeout_msecs is not used
for the lock sync_request_sem, so remove the timed locking too.

Signed-off-by: Binoy Jayan <binoy.jayan@linaro.org>
---
drivers/scsi/smartpqi/smartpqi.h | 4 +++-
drivers/scsi/smartpqi/smartpqi_init.c | 31 ++++++-------------------------
2 files changed, 9 insertions(+), 26 deletions(-)

diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h
index 07b6444..b4559b1 100644
--- a/drivers/scsi/smartpqi/smartpqi.h
+++ b/drivers/scsi/smartpqi/smartpqi.h
@@ -19,6 +19,8 @@
#if !defined(_SMARTPQI_H)
#define _SMARTPQI_H

+#include <linux/mutex.h>
+
#pragma pack(1)

#define PQI_DEVICE_SIGNATURE "PQI DREG"
@@ -961,7 +963,7 @@ struct pqi_ctrl_info {
unsigned int num_heartbeats_requested;
struct timer_list heartbeat_timer;

- struct semaphore sync_request_sem;
+ struct mutex sync_request_mutex;
struct semaphore lun_reset_sem;
};

diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index a535b26..4974f7e 100644
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -3444,29 +3444,11 @@ static int pqi_submit_raid_request_synchronous(struct pqi_ctrl_info *ctrl_info,
unsigned long msecs_blocked;
size_t iu_length;

- /*
- * Note that specifying PQI_SYNC_FLAGS_INTERRUPTABLE and a timeout value
- * are mutually exclusive.
- */
-
- if (flags & PQI_SYNC_FLAGS_INTERRUPTABLE) {
- if (down_interruptible(&ctrl_info->sync_request_sem))
+ if (flags & PQI_SYNC_FLAGS_INTERRUPTABLE)
+ if (mutex_lock_interruptible(&ctrl_info->sync_request_mutex))
return -ERESTARTSYS;
- } else {
- if (timeout_msecs == NO_TIMEOUT) {
- down(&ctrl_info->sync_request_sem);
- } else {
- start_jiffies = jiffies;
- if (down_timeout(&ctrl_info->sync_request_sem,
- msecs_to_jiffies(timeout_msecs)))
- return -ETIMEDOUT;
- msecs_blocked =
- jiffies_to_msecs(jiffies - start_jiffies);
- if (msecs_blocked >= timeout_msecs)
- return -ETIMEDOUT;
- timeout_msecs -= msecs_blocked;
- }
- }
+ else
+ mutex_lock(&ctrl_info->sync_request_mutex);

io_request = pqi_alloc_io_request(ctrl_info);

@@ -3508,7 +3490,7 @@ static int pqi_submit_raid_request_synchronous(struct pqi_ctrl_info *ctrl_info,

pqi_free_io_request(io_request);

- up(&ctrl_info->sync_request_sem);
+ mutex_unlock(&ctrl_info->sync_request_mutex);

return rc;
}
@@ -5540,8 +5522,7 @@ static struct pqi_ctrl_info *pqi_alloc_ctrl_info(int numa_node)
INIT_DELAYED_WORK(&ctrl_info->rescan_work, pqi_rescan_worker);
INIT_DELAYED_WORK(&ctrl_info->update_time_work, pqi_update_time_worker);

- sema_init(&ctrl_info->sync_request_sem,
- PQI_RESERVED_IO_SLOTS_SYNCHRONOUS_REQUESTS);
+ mutex_init(&ctrl_info->sync_request_mutex);
sema_init(&ctrl_info->lun_reset_sem, PQI_RESERVED_IO_SLOTS_LUN_RESET);

ctrl_info->ctrl_id = atomic_inc_return(&pqi_controller_count) - 1;
--
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