freebsd-dev/sys/vm/vm_reserv.h
Doug Moore 0d5fac2872 vm: alloc pages from reserv before breaking it
Function vm_reserv_reclaim_contig breaks a reservation with enough
free space to satisfy an allocation request and returns the free space
to the buddy allocator. Change the function to allocate the request
memory from the reservation before breaking it, and return that memory
to the caller. That avoids a second call to the buddy allocator and
guarantees successful allocation after breaking the reservation, where
that success is not currently guaranteed.

Reviewed by:	alc, kib (previous version)
Differential Revision:	https://reviews.freebsd.org/D33644
2021-12-24 12:59:16 -06:00

75 lines
2.9 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2002-2006 Rice University
* Copyright (c) 2007-2008 Alan L. Cox <alc@cs.rice.edu>
* All rights reserved.
*
* This software was developed for the FreeBSD Project by Alan L. Cox,
* Olivier Crameri, Peter Druschel, Sitaram Iyer, and Juan Navarro.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
* WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* Superpage reservation management definitions
*/
#ifndef _VM_RESERV_H_
#define _VM_RESERV_H_
#ifdef _KERNEL
#if VM_NRESERVLEVEL > 0
/*
* The following functions are only to be used by the virtual memory system.
*/
vm_page_t vm_reserv_alloc_contig(vm_object_t object, vm_pindex_t pindex,
int domain, int req, vm_page_t mpred, u_long npages,
vm_paddr_t low, vm_paddr_t high, u_long alignment,
vm_paddr_t boundary);
vm_page_t vm_reserv_alloc_page(vm_object_t object, vm_pindex_t pindex,
int domain, int req, vm_page_t mpred);
void vm_reserv_break_all(vm_object_t object);
boolean_t vm_reserv_free_page(vm_page_t m);
void vm_reserv_init(void);
bool vm_reserv_is_page_free(vm_page_t m);
int vm_reserv_level(vm_page_t m);
int vm_reserv_level_iffullpop(vm_page_t m);
vm_page_t vm_reserv_reclaim_contig(int domain, u_long npages,
vm_paddr_t low, vm_paddr_t high, u_long alignment,
vm_paddr_t boundary);
bool vm_reserv_reclaim_inactive(int domain);
void vm_reserv_rename(vm_page_t m, vm_object_t new_object,
vm_object_t old_object, vm_pindex_t old_object_offset);
int vm_reserv_size(int level);
vm_paddr_t vm_reserv_startup(vm_offset_t *vaddr, vm_paddr_t end);
vm_page_t vm_reserv_to_superpage(vm_page_t m);
#endif /* VM_NRESERVLEVEL > 0 */
#endif /* _KERNEL */
#endif /* !_VM_RESERV_H_ */