[S390] dasd: optimize cpu usage in goodcase

remove unnecessary dbf call, remove string operations for magic

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index c11770f..f15addf 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -730,7 +730,8 @@
 	struct dasd_ccw_req *cqr;
 	struct ccw1 *ccw;
 
-	cqr = dasd_smalloc_request("ECKD", 1 /* RCD */, ciw->count, device);
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* RCD */, ciw->count,
+				   device);
 
 	if (IS_ERR(cqr)) {
 		DBF_DEV_EVENT(DBF_WARNING, device, "%s",
@@ -934,8 +935,7 @@
 	struct dasd_eckd_private *private;
 
 	private = (struct dasd_eckd_private *) device->private;
-	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
-				   1 /* PSF */	+ 1 /* RSSD */ ,
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* PSF */	+ 1 /* RSSD */,
 				   (sizeof(struct dasd_psf_prssd_data) +
 				    sizeof(struct dasd_rssd_features)),
 				   device);
@@ -998,7 +998,7 @@
 	struct dasd_psf_ssc_data *psf_ssc_data;
 	struct ccw1 *ccw;
 
-	cqr = dasd_smalloc_request("ECKD", 1 /* PSF */ ,
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* PSF */ ,
 				  sizeof(struct dasd_psf_ssc_data),
 				  device);
 
@@ -1149,8 +1149,8 @@
 		goto out_err3;
 
 	/* Read Device Characteristics */
-	rc = dasd_generic_read_dev_chars(device, "ECKD", &private->rdc_data,
-					 64);
+	rc = dasd_generic_read_dev_chars(device, DASD_ECKD_MAGIC,
+					 &private->rdc_data, 64);
 	if (rc) {
 		DBF_EVENT(DBF_WARNING,
 			  "Read device characteristics failed, rc=%d for "
@@ -1217,8 +1217,7 @@
 
 	cplength = 8;
 	datasize = sizeof(struct DE_eckd_data) + 2*sizeof(struct LO_eckd_data);
-	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
-				   cplength, datasize, device);
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, cplength, datasize, device);
 	if (IS_ERR(cqr))
 		return cqr;
 	ccw = cqr->cpaddr;
@@ -1499,8 +1498,7 @@
 		return ERR_PTR(-EINVAL);
 	}
 	/* Allocate the format ccw request. */
-	fcp = dasd_smalloc_request(dasd_eckd_discipline.name,
-				   cplength, datasize, device);
+	fcp = dasd_smalloc_request(DASD_ECKD_MAGIC, cplength, datasize, device);
 	if (IS_ERR(fcp))
 		return fcp;
 
@@ -1783,8 +1781,8 @@
 		datasize += count*sizeof(struct LO_eckd_data);
 	}
 	/* Allocate the ccw request. */
-	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
-				   cplength, datasize, startdev);
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, cplength, datasize,
+				   startdev);
 	if (IS_ERR(cqr))
 		return cqr;
 	ccw = cqr->cpaddr;
@@ -1948,8 +1946,8 @@
 		cidaw * sizeof(unsigned long long);
 
 	/* Allocate the ccw request. */
-	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
-				   cplength, datasize, startdev);
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, cplength, datasize,
+				   startdev);
 	if (IS_ERR(cqr))
 		return cqr;
 	ccw = cqr->cpaddr;
@@ -2249,8 +2247,7 @@
 
 	/* Allocate the ccw request. */
 	itcw_size = itcw_calc_size(0, ctidaw, 0);
-	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
-				   0, itcw_size, startdev);
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 0, itcw_size, startdev);
 	if (IS_ERR(cqr))
 		return cqr;
 
@@ -2557,8 +2554,7 @@
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 
-	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
-				   1, 32, device);
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device);
 	if (IS_ERR(cqr)) {
 		DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 			    "Could not allocate initialization request");
@@ -2600,8 +2596,7 @@
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 
-	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
-				   1, 32, device);
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device);
 	if (IS_ERR(cqr)) {
 		DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 			    "Could not allocate initialization request");
@@ -2642,8 +2637,7 @@
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 
-	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
-				   1, 32, device);
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device);
 	if (IS_ERR(cqr)) {
 		DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 			    "Could not allocate initialization request");
@@ -2681,8 +2675,7 @@
 	struct ccw1 *ccw;
 	int rc;
 
-	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
-				   1 /* PSF */  + 1 /* RSSD */ ,
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* PSF */  + 1 /* RSSD */,
 				   (sizeof(struct dasd_psf_prssd_data) +
 				    sizeof(struct dasd_rssd_perf_stats_t)),
 				   device);
@@ -2828,7 +2821,7 @@
 	}
 
 	/* setup CCWs for PSF + RSSD */
-	cqr = dasd_smalloc_request("ECKD", 2 , 0, device);
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 2 , 0, device);
 	if (IS_ERR(cqr)) {
 		DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 			"Could not allocate initialization request");
@@ -3254,7 +3247,7 @@
 
 	/* Read Device Characteristics */
 	memset(&private->rdc_data, 0, sizeof(private->rdc_data));
-	rc = dasd_generic_read_dev_chars(device, "ECKD",
+	rc = dasd_generic_read_dev_chars(device, DASD_ECKD_MAGIC,
 					 &private->rdc_data, 64);
 	if (rc) {
 		DBF_EVENT(DBF_WARNING,