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>
diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
index ba9787d..bf76fc4 100644
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -800,14 +800,7 @@
int iscsi_task_attr;
int sam_task_attr;
- spin_lock_bh(&conn->sess->session_stats_lock);
- conn->sess->cmd_pdus++;
- if (conn->sess->se_sess->se_node_acl) {
- spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
- conn->sess->se_sess->se_node_acl->num_cmds++;
- spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
- }
- spin_unlock_bh(&conn->sess->session_stats_lock);
+ atomic_long_inc(&conn->sess->cmd_pdus);
hdr = (struct iscsi_scsi_req *) buf;
payload_length = ntoh24(hdr->dlength);
@@ -1254,14 +1247,7 @@
}
/* iSCSI write */
- spin_lock_bh(&conn->sess->session_stats_lock);
- conn->sess->rx_data_octets += payload_length;
- if (conn->sess->se_sess->se_node_acl) {
- spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
- conn->sess->se_sess->se_node_acl->write_bytes += payload_length;
- spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
- }
- spin_unlock_bh(&conn->sess->session_stats_lock);
+ atomic_long_add(payload_length, &conn->sess->rx_data_octets);
if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
pr_err("DataSegmentLength: %u is greater than"
@@ -2631,14 +2617,7 @@
return -1;
}
- spin_lock_bh(&conn->sess->session_stats_lock);
- conn->sess->tx_data_octets += datain.length;
- if (conn->sess->se_sess->se_node_acl) {
- spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
- conn->sess->se_sess->se_node_acl->read_bytes += datain.length;
- spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
- }
- spin_unlock_bh(&conn->sess->session_stats_lock);
+ atomic_long_add(datain.length, &conn->sess->tx_data_octets);
/*
* Special case for successfully execution w/ both DATAIN
* and Sense Data.
@@ -3163,9 +3142,7 @@
if (inc_stat_sn)
cmd->stat_sn = conn->stat_sn++;
- spin_lock_bh(&conn->sess->session_stats_lock);
- conn->sess->rsp_pdus++;
- spin_unlock_bh(&conn->sess->session_stats_lock);
+ atomic_long_inc(&conn->sess->rsp_pdus);
memset(hdr, 0, ISCSI_HDR_LEN);
hdr->opcode = ISCSI_OP_SCSI_CMD_RSP;
@@ -4114,9 +4091,7 @@
* hit default in the switch below.
*/
memset(buffer, 0xff, ISCSI_HDR_LEN);
- spin_lock_bh(&conn->sess->session_stats_lock);
- conn->sess->conn_digest_errors++;
- spin_unlock_bh(&conn->sess->session_stats_lock);
+ atomic_long_inc(&conn->sess->conn_digest_errors);
} else {
pr_debug("Got HeaderDigest CRC32C"
" 0x%08x\n", checksum);