RDS: limit the number of times we loop in rds_send_xmit

This will kick the RDS worker thread if we have been looping
too long.

Original commit from 2012 updated to include a change by
Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
that triggers "must_wake" if "rds_ib_recv_refill_one" fails.

Signed-off-by: Gerd Rausch <gerd.rausch@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Chris Mason 2012-02-03 11:07:54 -05:00 committed by David S. Miller
parent 907389b747
commit 65dedd7fe1

View File

@ -385,6 +385,7 @@ void rds_ib_recv_refill(struct rds_connection *conn, int prefill, gfp_t gfp)
unsigned int posted = 0;
int ret = 0;
bool can_wait = !!(gfp & __GFP_DIRECT_RECLAIM);
bool must_wake = false;
u32 pos;
/* the goal here is to just make sure that someone, somewhere
@ -405,6 +406,7 @@ void rds_ib_recv_refill(struct rds_connection *conn, int prefill, gfp_t gfp)
recv = &ic->i_recvs[pos];
ret = rds_ib_recv_refill_one(conn, recv, gfp);
if (ret) {
must_wake = true;
break;
}
@ -423,6 +425,11 @@ void rds_ib_recv_refill(struct rds_connection *conn, int prefill, gfp_t gfp)
}
posted++;
if ((posted > 128 && need_resched()) || posted > 8192) {
must_wake = true;
break;
}
}
/* We're doing flow control - update the window. */
@ -445,10 +452,13 @@ void rds_ib_recv_refill(struct rds_connection *conn, int prefill, gfp_t gfp)
* if we should requeue.
*/
if (rds_conn_up(conn) &&
((can_wait && rds_ib_ring_low(&ic->i_recv_ring)) ||
(must_wake ||
(can_wait && rds_ib_ring_low(&ic->i_recv_ring)) ||
rds_ib_ring_empty(&ic->i_recv_ring))) {
queue_delayed_work(rds_wq, &conn->c_recv_w, 1);
}
if (can_wait)
cond_resched();
}
/*