/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2002-2003, Network Appliance, Inc. All rights reserved.
*/
/*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
*
* MODULE: dapl_evd_dequeue.c
*
* PURPOSE: Event Management
*
* Description: Interfaces in this file are completely described in
* the uDAPL 1.1 API, Chapter 6, section 3
*
* $Id: dapl_evd_dequeue.c,v 1.9 2003/07/30 18:13:38 hobie16 Exp $
*/
#include "dapl.h"
#include "dapl_ring_buffer_util.h"
#include "dapl_evd_util.h"
/*
* dapl_evd_dequeue
*
* DAPL Requirements Version xxx, 6.3.2.7
*
* Remove first element from an event dispatcher
*
* Input:
* evd_handle
*
* Output:
* event
*
* Returns:
* DAT_SUCCESS
* DAT_INVALID_HANDLE
* DAT_INVALID_PARAMETER
* DAT_INVALID_STATE
* DAT_QUEUE_EMPTY
*/
DAT_RETURN dapl_evd_dequeue(
IN DAT_EVD_HANDLE evd_handle,
OUT DAT_EVENT *event)
{
DAPL_EVD *evd_ptr;
DAT_EVENT *local_event;
DAT_RETURN dat_status;
dapl_dbg_log(DAPL_DBG_TYPE_API,
"dapl_evd_dequeue (%p, %p)\n",
evd_handle,
event);
evd_ptr = (DAPL_EVD *)evd_handle;
dat_status = DAT_SUCCESS;
if (DAPL_BAD_HANDLE(evd_handle, DAPL_MAGIC_EVD)) {
dat_status = DAT_ERROR(DAT_INVALID_HANDLE, 0);
goto bail;
}
if (event == NULL) {
dat_status = DAT_ERROR(DAT_INVALID_PARAMETER, DAT_INVALID_ARG2);
goto bail;
}
/*
* We need to dequeue under lock, as the IB OS Access API
* restricts us from having multiple threads in CQ poll, and the
* DAPL 1.1 API allows multiple threads in dat_evd_dequeue()
*/
dapl_os_lock(&evd_ptr->header.lock);
/*
* Make sure there are no other waiters and the evd is active.
* Currently this means only the OPEN state is allowed.
*/
if (evd_ptr->evd_state != DAPL_EVD_STATE_OPEN ||
evd_ptr->catastrophic_overflow) {
dapl_os_unlock(&evd_ptr->header.lock);
dat_status = DAT_ERROR(DAT_INVALID_STATE, 0);
goto bail;
}
/*
* Try the EVD rbuf first; poll from the CQ only if that's empty.
* This keeps events in order if dat_evd_wait() has copied events
* from CQ to EVD.
*/
if (evd_ptr->pending_event_queue.head !=
evd_ptr->pending_event_queue.tail) {
local_event = (DAT_EVENT *)
dapls_rbuf_remove(&evd_ptr->pending_event_queue);
if (local_event != NULL) {
*event = *local_event;
dat_status = dapls_rbuf_add(&evd_ptr->free_event_queue,
local_event);
} else { /* should never happen */
dat_status = DAT_ERROR(DAT_INTERNAL_ERROR, 0);
}
} else if (evd_ptr->ib_cq_handle == IB_INVALID_HANDLE) {
dat_status = DAT_ERROR(DAT_QUEUE_EMPTY, 0);
} else if ((evd_ptr->evd_flags & (DAT_EVD_CONNECTION_FLAG |
DAT_EVD_CR_FLAG | DAT_EVD_ASYNC_FLAG)) == 0) {
/*
* No need to drop into kernel, just check the CQ.
*/
dat_status = dapls_evd_cq_poll_to_event(evd_ptr, event);
} else {
/* poll for events with threshold and timeout both 0 */
evd_ptr->threshold = 0;
dapl_os_unlock(&evd_ptr->header.lock);
dat_status = dapls_evd_copy_events(evd_ptr, 0);
if (dat_status != DAT_SUCCESS) {
dat_status = DAT_ERROR(DAT_QUEUE_EMPTY, 0);
goto bail;
}
dapl_os_lock(&evd_ptr->header.lock);
local_event = (DAT_EVENT *)dapls_rbuf_remove(
&evd_ptr->pending_event_queue);
if (local_event != NULL) {
*event = *local_event;
dat_status = dapls_rbuf_add(&evd_ptr->free_event_queue,
local_event);
} else { /* still didn't find anything */
dat_status = DAT_ERROR(DAT_QUEUE_EMPTY, 0);
}
}
dapl_os_unlock(&evd_ptr->header.lock);
bail:
dapl_dbg_log(DAPL_DBG_TYPE_RTN,
"dapl_evd_dequeue () returns 0x%x\n",
dat_status);
return (dat_status);
}