[SCSI] qla2xxx: Reduce request queue-size overhead with recent ISPs.

The original code to 'resize request-queues' based on iocb-counts
and employed during early ISP23xx testing was too
overly-pessimistic with regards to latencies in the firmware
pulling requests.  Recent ISPs can easily keep up processing a
stream of commands from an abbreviated (effectively, half the
original size) queue.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

2 files changed, 6 insertions, 64 deletions

diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index 01b7fc6f000b..1a84dbf82510 100644
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -176,8 +176,7 @@
 /* ISP request and response entry counts (37-65535) */
 #define REQUEST_ENTRY_CNT_2100          128     /* Number of request entries. */
 #define REQUEST_ENTRY_CNT_2200          2048    /* Number of request entries. */
-#define REQUEST_ENTRY_CNT_2XXX_EXT_MEM  4096    /* Number of request entries. */
-#define REQUEST_ENTRY_CNT_24XX          4096    /* Number of request entries. */
+#define REQUEST_ENTRY_CNT_24XX          2048    /* Number of request entries. */
 #define RESPONSE_ENTRY_CNT_2100         64      /* Number of response entries.*/
 #define RESPONSE_ENTRY_CNT_2300         512     /* Number of response entries.*/
 
diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c
index 997c83b07e8a..f90fd3774f19 100644
--- a/drivers/scsi/qla2xxx/qla_init.c
+++ b/drivers/scsi/qla2xxx/qla_init.c
@@ -20,7 +20,6 @@
 *  QLogic ISP2x00 Hardware Support Function Prototypes.
 */
 static int qla2x00_isp_firmware(scsi_qla_host_t *);
-static void qla2x00_resize_request_q(scsi_qla_host_t *);
 static int qla2x00_setup_chip(scsi_qla_host_t *);
 static int qla2x00_init_rings(scsi_qla_host_t *);
 static int qla2x00_fw_ready(scsi_qla_host_t *);
@@ -893,62 +892,6 @@ cont_alloc:
 }
 
 /**
- * qla2x00_resize_request_q() - Resize request queue given available ISP memory.
- * @ha: HA context
- *
- * Returns 0 on success.
- */
-static void
-qla2x00_resize_request_q(scsi_qla_host_t *vha)
-{
-        int rval;
-        uint16_t fw_iocb_cnt = 0;
-        uint16_t request_q_length = REQUEST_ENTRY_CNT_2XXX_EXT_MEM;
-        dma_addr_t request_dma;
-        request_t *request_ring;
-        struct qla_hw_data *ha = vha->hw;
-        struct req_que *req = ha->req_q_map[0];
-
-        /* Valid only on recent ISPs. */
-        if (IS_QLA2100(ha) || IS_QLA2200(ha))
-                return;
-
-        /* Retrieve IOCB counts available to the firmware. */
-        rval = qla2x00_get_resource_cnts(vha, NULL, NULL, NULL, &fw_iocb_cnt,
-                                        &ha->max_npiv_vports);
-        if (rval)
-                return;
-        /* No point in continuing if current settings are sufficient. */
-        if (fw_iocb_cnt < 1024)
-                return;
-        if (req->length >= request_q_length)
-                return;
-
-        /* Attempt to claim larger area for request queue. */
-        request_ring = dma_alloc_coherent(&ha->pdev->dev,
-            (request_q_length + 1) * sizeof(request_t), &request_dma,
-            GFP_KERNEL);
-        if (request_ring == NULL)
-                return;
-
-        /* Resize successful, report extensions. */
-        qla_printk(KERN_INFO, ha, "Extended memory detected (%d KB)...\n",
-            (ha->fw_memory_size + 1) / 1024);
-        qla_printk(KERN_INFO, ha, "Resizing request queue depth "
-            "(%d -> %d)...\n", req->length, request_q_length);
-
-        /* Clear old allocations. */
-        dma_free_coherent(&ha->pdev->dev,
-            (req->length + 1) * sizeof(request_t), req->ring,
-            req->dma);
-
-        /* Begin using larger queue. */
-        req->length = request_q_length;
-        req->ring = request_ring;
-        req->dma = request_dma;
-}
-
-/**
  * qla2x00_setup_chip() - Load and start RISC firmware.
  * @ha: HA context
  *
@@ -1005,11 +948,11 @@ qla2x00_setup_chip(scsi_qla_host_t *vha)
                                                 ha->max_npiv_vports =
                                                     MIN_MULTI_ID_FABRIC - 1;
                                 }
-                                if (!fw_major_version) {
-                                        qla2x00_resize_request_q(vha);
-                                        if (ql2xallocfwdump)
-                                                qla2x00_alloc_fw_dump(vha);
-                                }
+                                qla2x00_get_resource_cnts(vha, NULL, NULL,
+                                    NULL, NULL, &ha->max_npiv_vports);
+
+                                if (!fw_major_version && ql2xallocfwdump)
+                                        qla2x00_alloc_fw_dump(vha);
                         }
                 } else {
                         DEBUG2(printk(KERN_INFO