RE: [PATCH 1/5] use mutex instead of semaphore in Megaraid Mailbox driver

Patro, Sumant
2007-07-03T18:09:55Z

Thank you Matthias for the patch.

Regards,

Sumant

-----Original Message-----
From: Matthias Kaehlcke [mailto:matthias.kaehlcke@gmail.com]
Sent: Sunday, July 01, 2007 9:29 AM
To: DL-MegaRAID Linux; linux-scsi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org; akpm@linux-foundation.org
Subject: [PATCH 1/5] use mutex instead of semaphore in Megaraid Mailbox
driver

The Megaraid Mailbox driver uses a semaphore as mutex. Use the mutex API
instead of the (binary) semaphore.

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>

--

diff --git a/drivers/scsi/megaraid/mega_common.h
b/drivers/scsi/megaraid/mega_common.h
index 26e1e6c..fef9ac9 100644
--- a/drivers/scsi/megaraid/mega_common.h
+++ b/drivers/scsi/megaraid/mega_common.h
@@ -21,6 +21,7 @@
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/spinlock.h>
+#include <linux/mutex.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/blkdev.h>
diff --git a/drivers/scsi/megaraid/megaraid_mbox.c
b/drivers/scsi/megaraid/megaraid_mbox.c
index 04d0b69..2cecc64 100644
--- a/drivers/scsi/megaraid/megaraid_mbox.c
+++ b/drivers/scsi/megaraid/megaraid_mbox.c
@@ -3957,7 +3957,7 @@ megaraid_sysfs_alloc_resources(adapter_t *adapter)
megaraid_sysfs_free_resources(adapter);
}

- sema_init(&raid_dev->sysfs_sem, 1);
+ mutex_init(&raid_dev->sysfs_mtx);

init_waitqueue_head(&raid_dev->sysfs_wait_q);

@@ -4058,7 +4058,7 @@ megaraid_sysfs_get_ldmap(adapter_t *adapter)
/*
* Allow only one read at a time to go through the sysfs
attributes
*/
- down(&raid_dev->sysfs_sem);
+ mutex_lock(&raid_dev->sysfs_mtx);

uioc = raid_dev->sysfs_uioc;
mbox64 = raid_dev->sysfs_mbox64;
@@ -4134,7 +4134,7 @@ megaraid_sysfs_get_ldmap(adapter_t *adapter)

del_timer_sync(timerp);

- up(&raid_dev->sysfs_sem);
+ mutex_unlock(&raid_dev->sysfs_mtx);

return rval;
}
diff --git a/drivers/scsi/megaraid/megaraid_mbox.h
b/drivers/scsi/megaraid/megaraid_mbox.h
index 9de803c..626459d 100644
--- a/drivers/scsi/megaraid/megaraid_mbox.h
+++ b/drivers/scsi/megaraid/megaraid_mbox.h
@@ -168,7 +168,7 @@ typedef struct {
* @hw_error : set if FW not responding
* @fast_load : If set, skip physical device scanning
* @channel_class : channel class, RAID or SCSI
- * @sysfs_sem : semaphore to serialize access to sysfs
res.
+ * @sysfs_mtx : mutex to serialize access to sysfs
res.
* @sysfs_uioc : management packet to issue FW calls
from sysfs
* @sysfs_mbox64 : mailbox packet to issue FW calls from
sysfs
* @sysfs_buffer : data buffer for FW commands issued
from sysfs
@@ -208,7 +208,7 @@ typedef struct {
int hw_error;
int fast_load;
uint8_t channel_class;
- struct semaphore sysfs_sem;
+ struct mutex sysfs_mtx;
uioc_t *sysfs_uioc;
mbox64_t *sysfs_mbox64;
caddr_t sysfs_buffer;

--
Matthias Kaehlcke
Linux Application Developer
Barcelona

An ounce of practice is worth more than tons of preaching
(Mahatma Gandhi)