From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Simmons Date: Thu, 27 Feb 2020 16:15:49 -0500 Subject: [lustre-devel] [PATCH 481/622] lnet: change ln_mt_waitq to a completion. In-Reply-To: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> References: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> Message-ID: <1582838290-17243-482-git-send-email-jsimmons@infradead.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org From: Mr NeilBrown ln_mt_waitq is only waited on by a call to wait_event_interruptible_timeout(..., false, timeout); As 'false' is never 'true', this will always wait for the full timeout to expire. So the waitq is effectively pointless. To acheive the apparent intent of the waitq, change it to a completion. The completion adds a 'done' flag to a waitq so we can wait until a timeout or until a wakeup is requested. With this, a longer timeout would could be used, but that is left to a later patch. WC-bug-id: https://jira.whamcloud.com/browse/LU-12686 Lustre-commit: b81bcc6c6f0c ("LU-12686 lnet: change ln_mt_waitq to a completion.") Signed-off-by: Mr NeilBrown Reviewed-on: https://review.whamcloud.com/35874 Reviewed-by: Chris Horn Reviewed-by: James Simmons Reviewed-by: Oleg Drokin Signed-off-by: James Simmons --- include/linux/lnet/lib-types.h | 5 +++-- net/lnet/lnet/api-ni.c | 2 +- net/lnet/lnet/lib-move.c | 10 +++++++--- net/lnet/lnet/lib-msg.c | 2 +- net/lnet/lnet/router.c | 4 ++-- 5 files changed, 14 insertions(+), 9 deletions(-) diff --git a/include/linux/lnet/lib-types.h b/include/linux/lnet/lib-types.h index 22c2bc6..18d4e4e 100644 --- a/include/linux/lnet/lib-types.h +++ b/include/linux/lnet/lib-types.h @@ -1145,10 +1145,11 @@ struct lnet { */ bool ln_nis_from_mod_params; - /* waitq for the monitor thread. The monitor thread takes care of + /* + * completion for the monitor thread. The monitor thread takes care of * checking routes, timedout messages and resending messages. */ - wait_queue_head_t ln_mt_waitq; + struct completion ln_mt_wait_complete; /* per-cpt resend queues */ struct list_head **ln_mt_resendqs; diff --git a/net/lnet/lnet/api-ni.c b/net/lnet/lnet/api-ni.c index 79deaac..e66d9dc7 100644 --- a/net/lnet/lnet/api-ni.c +++ b/net/lnet/lnet/api-ni.c @@ -486,7 +486,7 @@ static int lnet_discover(struct lnet_process_id id, u32 force, spin_lock_init(&the_lnet.ln_eq_wait_lock); spin_lock_init(&the_lnet.ln_msg_resend_lock); init_waitqueue_head(&the_lnet.ln_eq_waitq); - init_waitqueue_head(&the_lnet.ln_mt_waitq); + init_completion(&the_lnet.ln_mt_wait_complete); mutex_init(&the_lnet.ln_lnd_mutex); } diff --git a/net/lnet/lnet/lib-move.c b/net/lnet/lnet/lib-move.c index 322998a..2f31f06 100644 --- a/net/lnet/lnet/lib-move.c +++ b/net/lnet/lnet/lib-move.c @@ -3276,8 +3276,12 @@ struct lnet_mt_event_info { min((unsigned int)alive_router_check_interval / lnet_current_net_count, lnet_transaction_timeout / 2)); - wait_event_interruptible_timeout(the_lnet.ln_mt_waitq, - false, HZ * interval); + wait_for_completion_interruptible_timeout(&the_lnet.ln_mt_wait_complete, + interval * HZ); + /* Must re-init the completion before testing anything, + * including ln_mt_state. + */ + reinit_completion(&the_lnet.ln_mt_wait_complete); } /* Shutting down */ @@ -3539,7 +3543,7 @@ void lnet_monitor_thr_stop(void) lnet_net_unlock(LNET_LOCK_EX); /* tell the monitor thread that we're shutting down */ - wake_up(&the_lnet.ln_mt_waitq); + complete(&the_lnet.ln_mt_wait_complete); /* block until monitor thread signals that it's done */ wait_for_completion(&the_lnet.ln_mt_signal); diff --git a/net/lnet/lnet/lib-msg.c b/net/lnet/lnet/lib-msg.c index 5c39ce3..d74ff53 100644 --- a/net/lnet/lnet/lib-msg.c +++ b/net/lnet/lnet/lib-msg.c @@ -640,7 +640,7 @@ list_add_tail(&msg->msg_list, the_lnet.ln_mt_resendqs[msg->msg_tx_cpt]); - wake_up(&the_lnet.ln_mt_waitq); + complete(&the_lnet.ln_mt_wait_complete); } int diff --git a/net/lnet/lnet/router.c b/net/lnet/lnet/router.c index bc9494d..7246eea 100644 --- a/net/lnet/lnet/router.c +++ b/net/lnet/lnet/router.c @@ -674,7 +674,7 @@ static void lnet_shuffle_seed(void) kfree(rnet); /* kick start the monitor thread to handle the added route */ - wake_up(&the_lnet.ln_mt_waitq); + complete(&the_lnet.ln_mt_wait_complete); return rc; } @@ -1419,7 +1419,7 @@ bool lnet_router_checker_active(void) lnet_net_lock(LNET_LOCK_EX); the_lnet.ln_routing = 1; lnet_net_unlock(LNET_LOCK_EX); - wake_up(&the_lnet.ln_mt_waitq); + complete(&the_lnet.ln_mt_wait_complete); return 0; failed: -- 1.8.3.1