From 1c6ce08297aa27bb00fbb4e9488ffdd8ade966b9 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 13 Feb 2018 10:47:59 +1100 Subject: [PATCH] staging: lustre: replace l_wait_event_exclusive_head() with wait_event_idle_exclusive This l_wait_event_exclusive_head() will wait indefinitely if the timeout is zero. If it does wait with a timeout and times out, the timeout for next time is set to zero. The can be mapped to a call to either wait_event_idle_exclusive() or wait_event_idle_exclusive_timeout() depending in the timeout setting. The current code arranges for LIFO queuing of waiters, but include/event.h doesn't support that yet. Until it does, fall back on FIFO with wait_event_idle_exclusive{,_timeout}(). Reviewed-by: James Simmons Signed-off-by: NeilBrown Reviewed-by: Patrick Farrell Signed-off-by: Greg Kroah-Hartman --- .../staging/lustre/lustre/ptlrpc/service.c | 43 +++++++++++-------- 1 file changed, 25 insertions(+), 18 deletions(-) diff --git a/drivers/staging/lustre/lustre/ptlrpc/service.c b/drivers/staging/lustre/lustre/ptlrpc/service.c index 6e3403417434..29fdb54f16ca 100644 --- a/drivers/staging/lustre/lustre/ptlrpc/service.c +++ b/drivers/staging/lustre/lustre/ptlrpc/service.c @@ -1897,15 +1897,6 @@ ptlrpc_check_rqbd_pool(struct ptlrpc_service_part *svcpt) } } -static int -ptlrpc_retry_rqbds(void *arg) -{ - struct ptlrpc_service_part *svcpt = arg; - - svcpt->scp_rqbd_timeout = 0; - return -ETIMEDOUT; -} - static inline int ptlrpc_threads_enough(struct ptlrpc_service_part *svcpt) { @@ -1968,13 +1959,17 @@ ptlrpc_server_request_incoming(struct ptlrpc_service_part *svcpt) return !list_empty(&svcpt->scp_req_incoming); } +/* We perfer lifo queuing, but kernel doesn't provide that yet. */ +#ifndef wait_event_idle_exclusive_lifo +#define wait_event_idle_exclusive_lifo wait_event_idle_exclusive +#define wait_event_idle_exclusive_lifo_timeout wait_event_idle_exclusive_timeout +#endif + static __attribute__((__noinline__)) int ptlrpc_wait_event(struct ptlrpc_service_part *svcpt, struct ptlrpc_thread *thread) { /* Don't exit while there are replies to be handled */ - struct l_wait_info lwi = LWI_TIMEOUT(svcpt->scp_rqbd_timeout, - ptlrpc_retry_rqbds, svcpt); /* XXX: Add this back when libcfs watchdog is merged upstream lc_watchdog_disable(thread->t_watchdog); @@ -1982,13 +1977,25 @@ ptlrpc_wait_event(struct ptlrpc_service_part *svcpt, cond_resched(); - l_wait_event_exclusive_head(svcpt->scp_waitq, - ptlrpc_thread_stopping(thread) || - ptlrpc_server_request_incoming(svcpt) || - ptlrpc_server_request_pending(svcpt, - false) || - ptlrpc_rqbd_pending(svcpt) || - ptlrpc_at_check(svcpt), &lwi); + if (svcpt->scp_rqbd_timeout == 0) + wait_event_idle_exclusive_lifo( + svcpt->scp_waitq, + ptlrpc_thread_stopping(thread) || + ptlrpc_server_request_incoming(svcpt) || + ptlrpc_server_request_pending(svcpt, + false) || + ptlrpc_rqbd_pending(svcpt) || + ptlrpc_at_check(svcpt)); + else if (0 == wait_event_idle_exclusive_lifo_timeout( + svcpt->scp_waitq, + ptlrpc_thread_stopping(thread) || + ptlrpc_server_request_incoming(svcpt) || + ptlrpc_server_request_pending(svcpt, + false) || + ptlrpc_rqbd_pending(svcpt) || + ptlrpc_at_check(svcpt), + svcpt->scp_rqbd_timeout)) + svcpt->scp_rqbd_timeout = 0; if (ptlrpc_thread_stopping(thread)) return -EINTR; -- 2.45.2