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Commit	Line	Data
	1	/*
	2	* Copyright (c) 2006 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
	5	*
	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
	25	*
	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
	27	*
	28	*/
	29	/*-
	30	* Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org>
	31	* All rights reserved.
	32	*
	33	* Redistribution and use in source and binary forms, with or without
	34	* modification, are permitted provided that the following conditions
	35	* are met:
	36	* 1. Redistributions of source code must retain the above copyright
	37	* notice, this list of conditions and the following disclaimer.
	38	* 2. Redistributions in binary form must reproduce the above copyright
	39	* notice, this list of conditions and the following disclaimer in the
	40	* documentation and/or other materials provided with the distribution.
	41	*
	42	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
	43	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	44	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	45	* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
	46	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	47	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	48	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	49	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	50	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	51	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	52	* SUCH DAMAGE.
	53	*/
	54
	55	#include <sys/kern_event.h>
	56	#include <sys/kern_memorystatus.h>
	57
	58	#include <kern/sched_prim.h>
	59	#include <kern/task.h>
	60	#include <kern/thread.h>
	61	#include <libkern/libkern.h>
	62	#include <sys/sysctl.h>
	63
	64	static void kern_memorystatus_thread(void);
	65
	66	int kern_memorystatus_wakeup = 0;
	67	int kern_memorystatus_pause = 0;
	68	int kern_memorystatus_level = 0;
	69	int kern_memorystatus_last_level = 0;
	70	unsigned int kern_memorystatus_kev_failure_count = 0;
	71
	72	SYSCTL_INT(_kern, OID_AUTO, memorystatus_level, CTLFLAG_RD, &kern_memorystatus_level, 0, "");
	73	SYSCTL_UINT(_kern, OID_AUTO, memorystatus_kev_failure_count, CTLFLAG_RD, &kern_memorystatus_kev_failure_count, 0, "");
	74
	75	__private_extern__ void
	76	kern_memorystatus_init(void)
	77	{
	78	(void)kernel_thread(kernel_task, kern_memorystatus_thread);
	79	}
	80
	81	static void
	82	kern_memorystatus_thread(void)
	83	{
	84	struct kev_msg ev_msg;
	85	int ret;
	86
	87	while(1) {
	88
	89	kern_memorystatus_last_level = kern_memorystatus_level;
	90
	91	ev_msg.vendor_code = KEV_VENDOR_APPLE;
	92	ev_msg.kev_class = KEV_SYSTEM_CLASS;
	93	ev_msg.kev_subclass = KEV_MEMORYSTATUS_SUBCLASS;
	94
	95	/* pass the memory status level in the event code (as percent used) */
	96	ev_msg.event_code = 100 - kern_memorystatus_last_level;
	97
	98	ev_msg.dv[0].data_length = 0;
	99
	100	ret = kev_post_msg(&ev_msg);
	101	if (ret) {
	102	kern_memorystatus_kev_failure_count++;
	103	printf("%s: kev_post_msg() failed, err %d\n", __func__, ret);
	104	}
	105
	106	assert_wait_timeout((event_t)&kern_memorystatus_pause, THREAD_UNINT, 1, 2501000NSEC_PER_USEC);
	107	(void)thread_block(THREAD_CONTINUE_NULL);
	108
	109	if (kern_memorystatus_level >= kern_memorystatus_last_level + 5 \|\|
	110	kern_memorystatus_level <= kern_memorystatus_last_level - 5)
	111	continue;
	112
	113	assert_wait(&kern_memorystatus_wakeup, THREAD_UNINT);
	114	(void)thread_block((thread_continue_t)kern_memorystatus_thread);
	115	}
	116	}