From 4ebb8795a746b2a3dbab4f12e4a1227603441a81 Mon Sep 17 00:00:00 2001 From: Long Li Date: Thu, 26 Mar 2020 22:33:01 -0700 Subject: cifs: smbd: Check and extend sender credits in interrupt context When a RDMA packet is received and server is extending send credits, we should check and unblock senders immediately in IRQ context. Doing it in a worker queue causes unnecessary delay and doesn't save much CPU on the receive path. Signed-off-by: Long Li Signed-off-by: Steve French --- fs/cifs/smbdirect.c | 38 +++++++++++++++----------------------- fs/cifs/smbdirect.h | 1 - 2 files changed, 15 insertions(+), 24 deletions(-) (limited to 'fs/cifs') diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c index a6ae29b3c4e7..8da43a500686 100644 --- a/fs/cifs/smbdirect.c +++ b/fs/cifs/smbdirect.c @@ -459,25 +459,6 @@ static void smbd_post_send_credits(struct work_struct *work) check_and_send_immediate(info); } -static void smbd_recv_done_work(struct work_struct *work) -{ - struct smbd_connection *info = - container_of(work, struct smbd_connection, recv_done_work); - - /* - * We may have new send credits granted from remote peer - * If any sender is blcoked on lack of credets, unblock it - */ - if (atomic_read(&info->send_credits)) - wake_up_interruptible(&info->wait_send_queue); - - /* - * Check if we need to send something to remote peer to - * grant more credits or respond to KEEP_ALIVE packet - */ - check_and_send_immediate(info); -} - /* Called from softirq, when recv is done */ static void recv_done(struct ib_cq *cq, struct ib_wc *wc) { @@ -546,8 +527,15 @@ static void recv_done(struct ib_cq *cq, struct ib_wc *wc) atomic_dec(&info->receive_credits); info->receive_credit_target = le16_to_cpu(data_transfer->credits_requested); - atomic_add(le16_to_cpu(data_transfer->credits_granted), - &info->send_credits); + if (le16_to_cpu(data_transfer->credits_granted)) { + atomic_add(le16_to_cpu(data_transfer->credits_granted), + &info->send_credits); + /* + * We have new send credits granted from remote peer + * If any sender is waiting for credits, unblock it + */ + wake_up_interruptible(&info->wait_send_queue); + } log_incoming(INFO, "data flags %d data_offset %d " "data_length %d remaining_data_length %d\n", @@ -563,7 +551,12 @@ static void recv_done(struct ib_cq *cq, struct ib_wc *wc) info->keep_alive_requested = KEEP_ALIVE_PENDING; } - queue_work(info->workqueue, &info->recv_done_work); + /* + * Check if we need to send something to remote peer to + * grant more credits or respond to KEEP_ALIVE packet + */ + check_and_send_immediate(info); + return; default: @@ -1762,7 +1755,6 @@ static struct smbd_connection *_smbd_get_connection( atomic_set(&info->send_payload_pending, 0); INIT_WORK(&info->disconnect_work, smbd_disconnect_rdma_work); - INIT_WORK(&info->recv_done_work, smbd_recv_done_work); INIT_WORK(&info->post_send_credits_work, smbd_post_send_credits); info->new_credits_offered = 0; spin_lock_init(&info->lock_new_credits_offered); diff --git a/fs/cifs/smbdirect.h b/fs/cifs/smbdirect.h index 6ff880a1e186..8ede915f2b24 100644 --- a/fs/cifs/smbdirect.h +++ b/fs/cifs/smbdirect.h @@ -67,7 +67,6 @@ struct smbd_connection { bool negotiate_done; struct work_struct disconnect_work; - struct work_struct recv_done_work; struct work_struct post_send_credits_work; spinlock_t lock_new_credits_offered; -- cgit