freebsd-skq/sys/vm/vm_reserv.h
markj 64730be2e1 Fix locking in vm_reserv_reclaim_contig().
We were not properly handling the case where the trylock of the
reservaton fails, in which case we could leak reservation lock.

Introduce a marker reservation to implement precise scanning in
vm_reserv_reclaim_contig().  Before, a race could result in early
termination of the scan in rare situations.  Use the marker's lock to
serialize scans of the partpop queue so that a global marker structure
can be used.  Modify vm_reserv_reclaim_inactive() to handle the presence
of a marker while minimizing the hold time of domain-global locks.

Reviewed by:	alc, jeff, kib
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D22392
2019-11-22 16:28:52 +00:00

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);
bool 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_ */