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authorChristof Schmitt <christof.schmitt@de.ibm.com>2009-07-13 15:06:03 +0200
committerJames Bottomley <James.Bottomley@HansenPartnership.com>2009-07-30 08:49:54 -0500
commitacf7b86150701de105aa8307b4b3f9dc533c45bb (patch)
tree3478d074c3a013d6c256d9c3098b6451a8a38264 /drivers
parentdfb3cf00e402686f671db697adbd8b9f4c219268 (diff)
[SCSI] zfcp: Acquire qdio_stat_lock when reading the queue utilization
req_q_util is not atomic, so the qdio_stat_lock must be held when reading this variable. Reviewed-by: Swen Schillig <swen@vnet.ibm.com> Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/s390/scsi/zfcp_sysfs.c7
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/s390/scsi/zfcp_sysfs.c b/drivers/s390/scsi/zfcp_sysfs.c
index 3e51e64d1108..0fe5cce818cb 100644
--- a/drivers/s390/scsi/zfcp_sysfs.c
+++ b/drivers/s390/scsi/zfcp_sysfs.c
@@ -494,9 +494,14 @@ static ssize_t zfcp_sysfs_adapter_q_full_show(struct device *dev,
struct Scsi_Host *scsi_host = class_to_shost(dev);
struct zfcp_adapter *adapter =
(struct zfcp_adapter *) scsi_host->hostdata[0];
+ u64 util;
+
+ spin_lock_bh(&adapter->qdio_stat_lock);
+ util = adapter->req_q_util;
+ spin_unlock_bh(&adapter->qdio_stat_lock);
return sprintf(buf, "%d %llu\n", atomic_read(&adapter->qdio_outb_full),
- (unsigned long long)adapter->req_q_util);
+ (unsigned long long)util);
}
static DEVICE_ATTR(queue_full, S_IRUGO, zfcp_sysfs_adapter_q_full_show, NULL);