Commit a7eef614 authored by Stefan Metzmacher's avatar Stefan Metzmacher Committed by Steve French
Browse files

smb: server: queue post_recv_credits_work in put_recvmsg() and avoid count_avail_recvmsg 



This is basically what the client is doing in put_receive_buffer().

It means we don't need complicated work to maintain count_avail_recvmsg.

But we keep the logic to queue post_recv_credits_work if the
peer raises the requested credit_target and put_receive_buffer()
is not called.

Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: default avatarStefan Metzmacher <metze@samba.org>
Acked-by: default avatarNamjae Jeon <linkinjeon@kernel.org>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent d4b86b49

fs/smb/server/transport_rdma.c

+11 −34
Original line number Diff line number Diff line
@@ -96,7 +96,6 @@ struct smb_direct_transport { 


	spinlock_t		receive_credit_lock;

	int			recv_credits;

	int			count_avail_recvmsg;

	int			recv_credit_target;



	atomic_t		send_credits;
@@ -183,13 +182,6 @@ static inline void 
	return (void *)recvmsg->packet;

}



static inline bool is_receive_credit_post_required(int receive_credits,

						   int avail_recvmsg_count)

{

	return receive_credits <= (smb_direct_receive_credit_max >> 3) &&

		avail_recvmsg_count >= (receive_credits >> 2);

}



static struct

smbdirect_recv_io *get_free_recvmsg(struct smb_direct_transport *t)

{
@@ -223,6 +215,8 @@ static void put_recvmsg(struct smb_direct_transport *t, 
	spin_lock(&sc->recv_io.free.lock);

	list_add(&recvmsg->list, &sc->recv_io.free.list);

	spin_unlock(&sc->recv_io.free.lock);



	queue_work(smb_direct_wq, &t->post_recv_credits_work);

}



static void enqueue_reassembly(struct smb_direct_transport *t,
@@ -530,7 +524,7 @@ static void recv_done(struct ib_cq *cq, struct ib_wc *wc) 
		struct smbdirect_data_transfer *data_transfer =

			(struct smbdirect_data_transfer *)recvmsg->packet;

		u32 remaining_data_length, data_offset, data_length;

		int avail_recvmsg_count, receive_credits;

		int old_recv_credit_target;



		if (wc->byte_len <

		    offsetof(struct smbdirect_data_transfer, padding)) {
@@ -565,18 +559,13 @@ static void recv_done(struct ib_cq *cq, struct ib_wc *wc) 
				sc->recv_io.reassembly.full_packet_received = false;

			else

				sc->recv_io.reassembly.full_packet_received = true;

		}



		spin_lock(&t->receive_credit_lock);

			receive_credits = --(t->recv_credits);

			avail_recvmsg_count = t->count_avail_recvmsg;

		t->recv_credits -= 1;

		spin_unlock(&t->receive_credit_lock);

		} else {

			spin_lock(&t->receive_credit_lock);

			receive_credits = --(t->recv_credits);

			avail_recvmsg_count = ++(t->count_avail_recvmsg);

			spin_unlock(&t->receive_credit_lock);

		}



		old_recv_credit_target = t->recv_credit_target;

		t->recv_credit_target =

				le16_to_cpu(data_transfer->credits_requested);

		atomic_add(le16_to_cpu(data_transfer->credits_granted),
@@ -589,10 +578,10 @@ static void recv_done(struct ib_cq *cq, struct ib_wc *wc) 
		if (atomic_read(&t->send_credits) > 0)

			wake_up(&t->wait_send_credits);



		if (is_receive_credit_post_required(receive_credits, avail_recvmsg_count))

		if (data_length) {

			if (t->recv_credit_target > old_recv_credit_target)

				queue_work(smb_direct_wq, &t->post_recv_credits_work);



		if (data_length) {

			enqueue_reassembly(t, recvmsg, (int)data_length);

			wake_up(&sc->recv_io.reassembly.wait_queue);

		} else
@@ -750,15 +739,6 @@ static int smb_direct_read(struct ksmbd_transport *t, char *buf, 
		sc->recv_io.reassembly.queue_length -= queue_removed;

		spin_unlock_irq(&sc->recv_io.reassembly.lock);



		spin_lock(&st->receive_credit_lock);

		st->count_avail_recvmsg += queue_removed;

		if (is_receive_credit_post_required(st->recv_credits, st->count_avail_recvmsg)) {

			spin_unlock(&st->receive_credit_lock);

			queue_work(smb_direct_wq, &st->post_recv_credits_work);

		} else {

			spin_unlock(&st->receive_credit_lock);

		}



		sc->recv_io.reassembly.first_entry_offset = offset;

		ksmbd_debug(RDMA,

			    "returning to thread data_read=%d reassembly_data_length=%d first_entry_offset=%d\n",
@@ -810,7 +790,6 @@ static void smb_direct_post_recv_credits(struct work_struct *work) 


	spin_lock(&t->receive_credit_lock);

	t->recv_credits += credits;

	t->count_avail_recvmsg -= credits;

	spin_unlock(&t->receive_credit_lock);



	spin_lock(&t->lock_new_recv_credits);
@@ -1826,7 +1805,6 @@ static int smb_direct_init_params(struct smb_direct_transport *t, 
	}



	t->recv_credits = 0;

	t->count_avail_recvmsg = 0;



	sp->recv_credit_max = smb_direct_receive_credit_max;

	t->recv_credit_target = 10;
@@ -1914,7 +1892,6 @@ static int smb_direct_create_pools(struct smb_direct_transport *t) 
		recvmsg->sge.length = 0;

		list_add(&recvmsg->list, &sc->recv_io.free.list);

	}

	t->count_avail_recvmsg = sp->recv_credit_max;



	return 0;

err: