[SCSI] zfcp: Simplify latency lock handling
Christof Schmitt [Mon, 2 Mar 2009 12:08:57 +0000 (13:08 +0100)]
The lock only needs to protect the softirq context called from qdio
against the userspace context called from sysfs. spin_lock and
spin_lock_bh is enough.

Acked-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>

drivers/s390/scsi/zfcp_fsf.c
drivers/s390/scsi/zfcp_sysfs.c

index 638cd5a..cce6981 100644 (file)
@@ -2069,7 +2069,6 @@ static void zfcp_fsf_req_latency(struct zfcp_fsf_req *req)
        struct fsf_qual_latency_info *lat_inf;
        struct latency_cont *lat;
        struct zfcp_unit *unit = req->unit;
-       unsigned long flags;
 
        lat_inf = &req->qtcb->prefix.prot_status_qual.latency_info;
 
@@ -2087,11 +2086,11 @@ static void zfcp_fsf_req_latency(struct zfcp_fsf_req *req)
                return;
        }
 
-       spin_lock_irqsave(&unit->latencies.lock, flags);
+       spin_lock(&unit->latencies.lock);
        zfcp_fsf_update_lat(&lat->channel, lat_inf->channel_lat);
        zfcp_fsf_update_lat(&lat->fabric, lat_inf->fabric_lat);
        lat->counter++;
-       spin_unlock_irqrestore(&unit->latencies.lock, flags);
+       spin_unlock(&unit->latencies.lock);
 }
 
 #ifdef CONFIG_BLK_DEV_IO_TRACE
index 9e9931a..14e38c2 100644 (file)
@@ -318,10 +318,9 @@ zfcp_sysfs_unit_##_name##_latency_show(struct device *dev,         \
        struct zfcp_unit *unit = sdev->hostdata;                        \
        struct zfcp_latencies *lat = &unit->latencies;                  \
        struct zfcp_adapter *adapter = unit->port->adapter;             \
-       unsigned long flags;                                            \
        unsigned long long fsum, fmin, fmax, csum, cmin, cmax, cc;      \
                                                                        \
-       spin_lock_irqsave(&lat->lock, flags);                           \
+       spin_lock_bh(&lat->lock);                                       \
        fsum = lat->_name.fabric.sum * adapter->timer_ticks;            \
        fmin = lat->_name.fabric.min * adapter->timer_ticks;            \
        fmax = lat->_name.fabric.max * adapter->timer_ticks;            \
@@ -329,7 +328,7 @@ zfcp_sysfs_unit_##_name##_latency_show(struct device *dev,          \
        cmin = lat->_name.channel.min * adapter->timer_ticks;           \
        cmax = lat->_name.channel.max * adapter->timer_ticks;           \
        cc  = lat->_name.counter;                                       \
-       spin_unlock_irqrestore(&lat->lock, flags);                      \
+       spin_unlock_bh(&lat->lock);                                     \
                                                                        \
        do_div(fsum, 1000);                                             \
        do_div(fmin, 1000);                                             \