Commits
Steve Wise committed b33bd0cbfa1
RDMA/cxgb4: Endpoint timeout fixes 1) timedout endpoint processing can be starved. If there are continual CPL messages flowing into the driver, the endpoint timeout processing can be starved. This condition exposed the other bugs below. Solution: In process_work(), call process_timedout_eps() after each CPL is processed. 2) Connection events can be processed even though the endpoint is on the timeout list. If the endpoint is scheduled for timeout processing, then we must ignore MPA Start Requests and Replies. Solution: Change stop_ep_timer() to return 1 if the ep has already been queued for timeout processing. All the callers of stop_ep_timer() need to check this and act accordingly. There are just a few cases where the caller needs to do something different if stop_ep_timer() returns 1: 1) in process_mpa_reply(), ignore the reply and process_timeout() will abort the connection. 2) in process_mpa_request, ignore the request and process_timeout() will abort the connection. It is ok for callers of stop_ep_timer() to abort the connection since that will leave the state in ABORTING or DEAD, and process_timeout() now ignores timeouts when the ep is in these states. 3) Double insertion on the timeout list. Since the endpoint timers are used for connection setup and teardown, we need to guard against the possibility that an endpoint is already on the timeout list. This is a rare condition and only seen under heavy load and in the presense of the above 2 bugs. Solution: In ep_timeout(), don't queue the endpoint if it is already on the queue. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Roland Dreier <roland@purestorage.com>