target: Remove se_session.sess_wait_list

Since we set se_session.sess_tearing_down and stop new commands from
being added to se_session.sess_cmd_list before we wait for commands to
finish when freeing a session, there's no need for a separate
sess_wait_list -- if we let new commands be added to sess_cmd_list
after setting sess_tearing_down, that would be a bug that breaks the
logic of waiting in-flight commands.

Also rename target_splice_sess_cmd_list() to
target_sess_cmd_list_set_waiting(), since we are no longer splicing
onto a separate list.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Roland Dreier 2012-07-16 11:04:42 -07:00 committed by Nicholas Bellinger
parent e1013f1437
commit 1c7b13fe65
4 changed files with 12 additions and 15 deletions

View File

@ -464,7 +464,7 @@ static int tcm_qla2xxx_shutdown_session(struct se_session *se_sess)
vha = sess->vha; vha = sess->vha;
spin_lock_irqsave(&vha->hw->hardware_lock, flags); spin_lock_irqsave(&vha->hw->hardware_lock, flags);
target_splice_sess_cmd_list(se_sess); target_sess_cmd_list_set_waiting(se_sess);
spin_unlock_irqrestore(&vha->hw->hardware_lock, flags); spin_unlock_irqrestore(&vha->hw->hardware_lock, flags);
return 1; return 1;

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@ -232,7 +232,6 @@ struct se_session *transport_init_session(void)
INIT_LIST_HEAD(&se_sess->sess_list); INIT_LIST_HEAD(&se_sess->sess_list);
INIT_LIST_HEAD(&se_sess->sess_acl_list); INIT_LIST_HEAD(&se_sess->sess_acl_list);
INIT_LIST_HEAD(&se_sess->sess_cmd_list); INIT_LIST_HEAD(&se_sess->sess_cmd_list);
INIT_LIST_HEAD(&se_sess->sess_wait_list);
spin_lock_init(&se_sess->sess_cmd_lock); spin_lock_init(&se_sess->sess_cmd_lock);
kref_init(&se_sess->sess_kref); kref_init(&se_sess->sess_kref);
@ -2478,28 +2477,27 @@ int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
} }
EXPORT_SYMBOL(target_put_sess_cmd); EXPORT_SYMBOL(target_put_sess_cmd);
/* target_splice_sess_cmd_list - Split active cmds into sess_wait_list /* target_sess_cmd_list_set_waiting - Flag all commands in
* @se_sess: session to split * sess_cmd_list to complete cmd_wait_comp. Set
* sess_tearing_down so no more commands are queued.
* @se_sess: session to flag
*/ */
void target_splice_sess_cmd_list(struct se_session *se_sess) void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
{ {
struct se_cmd *se_cmd; struct se_cmd *se_cmd;
unsigned long flags; unsigned long flags;
WARN_ON(!list_empty(&se_sess->sess_wait_list));
INIT_LIST_HEAD(&se_sess->sess_wait_list);
spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
WARN_ON(se_sess->sess_tearing_down);
se_sess->sess_tearing_down = 1; se_sess->sess_tearing_down = 1;
list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list); list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list)
list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
se_cmd->cmd_wait_set = 1; se_cmd->cmd_wait_set = 1;
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
} }
EXPORT_SYMBOL(target_splice_sess_cmd_list); EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
/* target_wait_for_sess_cmds - Wait for outstanding descriptors /* target_wait_for_sess_cmds - Wait for outstanding descriptors
* @se_sess: session to wait for active I/O * @se_sess: session to wait for active I/O
@ -2513,7 +2511,7 @@ void target_wait_for_sess_cmds(
bool rc = false; bool rc = false;
list_for_each_entry_safe(se_cmd, tmp_cmd, list_for_each_entry_safe(se_cmd, tmp_cmd,
&se_sess->sess_wait_list, se_cmd_list) { &se_sess->sess_cmd_list, se_cmd_list) {
list_del(&se_cmd->se_cmd_list); list_del(&se_cmd->se_cmd_list);
pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:" pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"

View File

@ -613,7 +613,6 @@ struct se_session {
struct list_head sess_list; struct list_head sess_list;
struct list_head sess_acl_list; struct list_head sess_acl_list;
struct list_head sess_cmd_list; struct list_head sess_cmd_list;
struct list_head sess_wait_list;
spinlock_t sess_cmd_lock; spinlock_t sess_cmd_lock;
struct kref sess_kref; struct kref sess_kref;
}; };

View File

@ -122,7 +122,7 @@ int transport_check_aborted_status(struct se_cmd *, int);
int transport_send_check_condition_and_sense(struct se_cmd *, u8, int); int transport_send_check_condition_and_sense(struct se_cmd *, u8, int);
int target_put_sess_cmd(struct se_session *, struct se_cmd *); int target_put_sess_cmd(struct se_session *, struct se_cmd *);
void target_splice_sess_cmd_list(struct se_session *); void target_sess_cmd_list_set_waiting(struct se_session *);
void target_wait_for_sess_cmds(struct se_session *, int); void target_wait_for_sess_cmds(struct se_session *, int);
int core_alua_check_nonop_delay(struct se_cmd *); int core_alua_check_nonop_delay(struct se_cmd *);