diff options
authorNicholas Bellinger <nab@linux-iscsi.org>2013-10-03 14:03:59 -0700
committerNicholas Bellinger <nab@linux-iscsi.org>2013-10-03 14:22:45 -0700
commit9e20ae339721d614a1b0768c48bd73b456ff7905 (patch)
parentf56cbbb4b5871e5bc2838ddeeba5b29debc2a734 (diff)
iscsi-target; Allow an extra tag_num / 2 number of percpu_ida tags
This patch bumps the default number of tags allocated per session by iscsi-target via transport_alloc_session_tags() -> percpu_ida_init() by another (tag_num / 2). This is done to take into account the tags waiting to be acknowledged and released in iscsit_ack_from_expstatsn(), but who's number are not directly limited by the CmdSN Window queue_depth being enforced by the target. Using a larger value here is also useful to prevent percpu_ida_alloc() from having to steal tags from other CPUs when no tags are available on the local CPU, while waiting for unacknowledged tags to be released. Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/target/iscsi/iscsi_target_nego.c b/drivers/target/iscsi/iscsi_target_nego.c
index 14d1aed5af1d..ef6d836a4d09 100644
--- a/drivers/target/iscsi/iscsi_target_nego.c
+++ b/drivers/target/iscsi/iscsi_target_nego.c
@@ -1192,7 +1192,7 @@ get_target:
tag_num = max_t(u32, ISCSIT_MIN_TAGS, queue_depth);
- tag_num += ISCSIT_EXTRA_TAGS;
+ tag_num += (tag_num / 2) + ISCSIT_EXTRA_TAGS;
tag_size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
ret = transport_alloc_session_tags(sess->se_sess, tag_num, tag_size);