1 /* 2 * Copyright (c) 2024 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 #include <stdbool.h> 29 #include <stdint.h> 30 31 #pragma once 32 33 __BEGIN_DECLS 34 #if XNU_KERNEL_PRIVATE 35 36 /* TODO: migrate other xnu-private interfaces from kern_memorystatus.h */ 37 38 /* 39 * Return the minimum number of available pages jetsam requires before it 40 * begins killing non-idle processes. This is useful for some pageout 41 * mechanisms to avoid deadlock. 42 */ 43 extern uint32_t memorystatus_get_critical_page_shortage_threshold(void); 44 45 /* 46 * Return the minimum number of available pages jetsam requires before it 47 * begins killing idle processes. This is consumed by the vm pressure 48 * notification system in the absence of the compressor. 49 */ 50 extern uint32_t memorystatus_get_idle_exit_page_shortage_threshold(void); 51 52 /* 53 * Return the minimum number of available pages jetsam requires before it 54 * begins killing processes which have violated their soft memory limit. This 55 * is consumed by the vm pressure notification system in the absence of the 56 * compressor. 57 */ 58 extern uint32_t memorystatus_get_soft_memlimit_page_shortage_threshold(void); 59 60 /* 61 * Return the current number of available pages in the system. 62 */ 63 extern uint32_t memorystatus_get_available_page_count(void); 64 65 /* 66 * Set the available page count and consider engaging response measures (e.g. 67 * waking jetsam thread/pressure-notification thread). 68 */ 69 extern void memorystatus_update_available_page_count(uint32_t available_pages); 70 71 /* 72 * Override fast-jetsam support. If override is enabled, fast-jetsam will be 73 * disabled. 74 */ 75 extern void memorystatus_fast_jetsam_override(bool enable_override); 76 77 #endif /* XNU_KERNEL_PRIVATE */ 78 __END_DECLS 79