SUNRPC: Enqueue swapper tagged RPCs at the head of the transmit queue

Avoid memory starvation by giving RPCs that are tagged with the
RPC_TASK_SWAPPER flag the highest priority.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This commit is contained in:
Trond Myklebust 2018-09-08 14:22:41 -04:00
parent 75891f502f
commit 86aeee0eb6

View File

@ -1112,6 +1112,17 @@ xprt_request_enqueue_transmit(struct rpc_task *task)
INIT_LIST_HEAD(&req->rq_xmit2);
goto out;
}
} else if (RPC_IS_SWAPPER(task)) {
list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) {
if (pos->rq_cong || pos->rq_bytes_sent)
continue;
if (RPC_IS_SWAPPER(pos->rq_task))
continue;
/* Note: req is added _before_ pos */
list_add_tail(&req->rq_xmit, &pos->rq_xmit);
INIT_LIST_HEAD(&req->rq_xmit2);
goto out;
}
} else {
list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) {
if (pos->rq_task->tk_owner != task->tk_owner)