Move the IB completion handler error handling code into the new
function srp_handle_qp_err(). Convert srp_target_port.qp_in_error
from int to bool. Move the initialization of that variable into
srp_connect_target(). Help the CPU branch predictor by making it
clear that IB_WC_SUCCESS is the most likely case.

Signed-off-by: Bart Van Assche <[email protected]>
Cc: David Dillow <[email protected]>
Cc: Roland Dreier <[email protected]>
---
 drivers/infiniband/ulp/srp/ib_srp.c |   37 ++++++++++++++++++----------------
 drivers/infiniband/ulp/srp/ib_srp.h |    2 +-
 2 files changed, 21 insertions(+), 18 deletions(-)

diff --git a/drivers/infiniband/ulp/srp/ib_srp.c 
b/drivers/infiniband/ulp/srp/ib_srp.c
index 5543c2b..6279343 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -515,6 +515,8 @@ static int srp_connect_target(struct srp_target_port 
*target)
        int retries = 3;
        int ret;
 
+       target->qp_in_error = false;
+
        ret = srp_lookup_path(target);
        if (ret)
                return ret;
@@ -648,7 +650,6 @@ static int srp_reconnect_target(struct srp_target_port 
*target)
        for (i = 0; i < SRP_SQ_SIZE; ++i)
                list_add(&target->tx_ring[i]->list, &target->free_tx);
 
-       target->qp_in_error = 0;
        ret = srp_connect_target(target);
        if (ret)
                goto err;
@@ -1215,6 +1216,15 @@ static void srp_handle_recv(struct srp_target_port 
*target, struct ib_wc *wc)
                             PFX "Recv failed with error code %d\n", res);
 }
 
+static void srp_handle_qp_err(enum ib_wc_status wc_status,
+                             enum ib_wc_opcode wc_opcode,
+                             struct srp_target_port *target)
+{
+       shost_printk(KERN_ERR, target->scsi_host, PFX "failed %s status %d\n",
+                    wc_opcode & IB_WC_RECV ? "receive" : "send", wc_status);
+       target->qp_in_error = true;
+}
+
 static void srp_recv_completion(struct ib_cq *cq, void *target_ptr)
 {
        struct srp_target_port *target = target_ptr;
@@ -1222,15 +1232,12 @@ static void srp_recv_completion(struct ib_cq *cq, void 
*target_ptr)
 
        ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
        while (ib_poll_cq(cq, 1, &wc) > 0) {
-               if (wc.status) {
-                       shost_printk(KERN_ERR, target->scsi_host,
-                                    PFX "failed receive status %d\n",
-                                    wc.status);
-                       target->qp_in_error = 1;
+               if (likely(wc.status == IB_WC_SUCCESS)) {
+                       srp_handle_recv(target, &wc);
+               } else {
+                       srp_handle_qp_err(wc.status, wc.opcode, target);
                        break;
                }
-
-               srp_handle_recv(target, &wc);
        }
 }
 
@@ -1241,16 +1248,13 @@ static void srp_send_completion(struct ib_cq *cq, void 
*target_ptr)
        struct srp_iu *iu;
 
        while (ib_poll_cq(cq, 1, &wc) > 0) {
-               if (wc.status) {
-                       shost_printk(KERN_ERR, target->scsi_host,
-                                    PFX "failed send status %d\n",
-                                    wc.status);
-                       target->qp_in_error = 1;
+               if (likely(wc.status == IB_WC_SUCCESS)) {
+                       iu = (struct srp_iu *) (uintptr_t) wc.wr_id;
+                       list_add(&iu->list, &target->free_tx);
+               } else {
+                       srp_handle_qp_err(wc.status, wc.opcode, target);
                        break;
                }
-
-               iu = (struct srp_iu *) (uintptr_t) wc.wr_id;
-               list_add(&iu->list, &target->free_tx);
        }
 }
 
@@ -2237,7 +2241,6 @@ static ssize_t srp_create_target(struct device *dev,
        if (ret)
                goto err_free_ib;
 
-       target->qp_in_error = 0;
        ret = srp_connect_target(target);
        if (ret) {
                shost_printk(KERN_ERR, target->scsi_host,
diff --git a/drivers/infiniband/ulp/srp/ib_srp.h 
b/drivers/infiniband/ulp/srp/ib_srp.h
index e3a6304..f0daeb3 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.h
+++ b/drivers/infiniband/ulp/srp/ib_srp.h
@@ -180,7 +180,7 @@ struct srp_target_port {
        struct list_head        list;
        struct completion       done;
        int                     status;
-       int                     qp_in_error;
+       bool                    qp_in_error;
 
        struct completion       tsk_mgmt_done;
        u8                      tsk_mgmt_status;
-- 
1.7.7


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