iscsi-target: Convert iscsi_session statistics to atomic_long_t

This patch converts a handful of iscsi_session statistics to type
atomic_long_t, instead of using iscsi_session->session_stats_lock
when incrementing these values.

More importantly, go ahead and drop the spinlock usage within
iscsit_setup_scsi_cmd(), iscsit_check_dataout_hdr(),
iscsit_send_datain(), and iscsit_build_rsp_pdu() fast-path code.

(Squash in Roland's  target: Remove write-only stats fields and lock
from struct se_node_acl)

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 12 insertions, 10 deletions

diff --git a/drivers/target/iscsi/iscsi_target_stat.c b/drivers/target/iscsi/iscsi_target_stat.c
index f788e8b5e855..103395510307 100644
--- a/drivers/target/iscsi/iscsi_target_stat.c
+++ b/drivers/target/iscsi/iscsi_target_stat.c
@@ -792,7 +792,8 @@ static ssize_t iscsi_stat_sess_show_attr_cmd_pdus(
         if (se_sess) {
                 sess = se_sess->fabric_sess_ptr;
                 if (sess)
-                        ret = snprintf(page, PAGE_SIZE, "%u\n", sess->cmd_pdus);
+                        ret = snprintf(page, PAGE_SIZE, "%lu\n",
+                                       atomic_long_read(&sess->cmd_pdus));
         }
         spin_unlock_bh(&se_nacl->nacl_sess_lock);
 
@@ -815,7 +816,8 @@ static ssize_t iscsi_stat_sess_show_attr_rsp_pdus(
         if (se_sess) {
                 sess = se_sess->fabric_sess_ptr;
                 if (sess)
-                        ret = snprintf(page, PAGE_SIZE, "%u\n", sess->rsp_pdus);
+                        ret = snprintf(page, PAGE_SIZE, "%lu\n",
+                                       atomic_long_read(&sess->rsp_pdus));
         }
         spin_unlock_bh(&se_nacl->nacl_sess_lock);
 
@@ -838,8 +840,8 @@ static ssize_t iscsi_stat_sess_show_attr_txdata_octs(
         if (se_sess) {
                 sess = se_sess->fabric_sess_ptr;
                 if (sess)
-                        ret = snprintf(page, PAGE_SIZE, "%llu\n",
-                                (unsigned long long)sess->tx_data_octets);
+                        ret = snprintf(page, PAGE_SIZE, "%lu\n",
+                                       atomic_long_read(&sess->tx_data_octets));
         }
         spin_unlock_bh(&se_nacl->nacl_sess_lock);
 
@@ -862,8 +864,8 @@ static ssize_t iscsi_stat_sess_show_attr_rxdata_octs(
         if (se_sess) {
                 sess = se_sess->fabric_sess_ptr;
                 if (sess)
-                        ret = snprintf(page, PAGE_SIZE, "%llu\n",
-                                (unsigned long long)sess->rx_data_octets);
+                        ret = snprintf(page, PAGE_SIZE, "%lu\n",
+                                       atomic_long_read(&sess->rx_data_octets));
         }
         spin_unlock_bh(&se_nacl->nacl_sess_lock);
 
@@ -886,8 +888,8 @@ static ssize_t iscsi_stat_sess_show_attr_conn_digest_errors(
         if (se_sess) {
                 sess = se_sess->fabric_sess_ptr;
                 if (sess)
-                        ret = snprintf(page, PAGE_SIZE, "%u\n",
-                                        sess->conn_digest_errors);
+                        ret = snprintf(page, PAGE_SIZE, "%lu\n",
+                                       atomic_long_read(&sess->conn_digest_errors));
         }
         spin_unlock_bh(&se_nacl->nacl_sess_lock);
 
@@ -910,8 +912,8 @@ static ssize_t iscsi_stat_sess_show_attr_conn_timeout_errors(
         if (se_sess) {
                 sess = se_sess->fabric_sess_ptr;
                 if (sess)
-                        ret = snprintf(page, PAGE_SIZE, "%u\n",
-                                        sess->conn_timeout_errors);
+                        ret = snprintf(page, PAGE_SIZE, "%lu\n",
+                                       atomic_long_read(&sess->conn_timeout_errors));
         }
         spin_unlock_bh(&se_nacl->nacl_sess_lock);