d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
467535dcfa
freebsd-skq/sys/vm/pmap.h
Mark Johnston 01cef4caa7 Remove page locking from pmap_mincore(). 
After r352110 the page lock no longer protects a page's identity, so
there is no purpose in locking the page in pmap_mincore().  Instead,
if vm.mincore_mapped is set to the non-default value of 0, re-lookup
the page after acquiring its object lock, which holds the page's
identity stable.

The change removes the last callers of vm_page_pa_tryrelock(), so
remove it.

Reviewed by:	kib
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D21823
2019-10-16 22:03:27 +00:00

176 lines
7.0 KiB
C
Raw Blame History

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* The Mach Operating System project at Carnegie-Mellon University.
*
* 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.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* from: @(#)pmap.h 8.1 (Berkeley) 6/11/93
*
*
* Copyright (c) 1987, 1990 Carnegie-Mellon University.
* All rights reserved.
*
* Author: Avadis Tevanian, Jr.
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*
* $FreeBSD$
*/
/*
* Machine address mapping definitions -- machine-independent
* section. [For machine-dependent section, see "machine/pmap.h".]
*/
#ifndef _PMAP_VM_
#define _PMAP_VM_
/*
* Each machine dependent implementation is expected to
* keep certain statistics. They may do this anyway they
* so choose, but are expected to return the statistics
* in the following structure.
*/
struct pmap_statistics {
long resident_count; /* # of pages mapped (total) */
long wired_count; /* # of pages wired */
};
typedef struct pmap_statistics *pmap_statistics_t;
/*
* Each machine-dependent implementation is required to provide:
*
* vm_memattr_t pmap_page_get_memattr(vm_page_t);
* boolean_t pmap_page_is_mapped(vm_page_t);
* boolean_t pmap_page_is_write_mapped(vm_page_t);
* void pmap_page_set_memattr(vm_page_t, vm_memattr_t);
*/
#include <machine/pmap.h>
#ifdef _KERNEL
struct thread;
/*
* Updates to kernel_vm_end are synchronized by the kernel_map's system mutex.
*/
extern vm_offset_t kernel_vm_end;
/*
* Flags for pmap_enter(). The bits in the low-order byte are reserved
* for the protection code (vm_prot_t) that describes the fault type.
* Bits 24 through 31 are reserved for the pmap's internal use.
*/
#define PMAP_ENTER_NOSLEEP 0x00000100
#define PMAP_ENTER_WIRED 0x00000200
#define PMAP_ENTER_RESERVED 0xFF000000
/*
* Define the maximum number of machine-dependent reference bits that are
* cleared by a call to pmap_ts_referenced(). This limit serves two purposes.
* First, it bounds the cost of reference bit maintenance on widely shared
* pages. Second, it prevents numeric overflow during maintenance of a
* widely shared page's "act_count" field. An overflow could result in the
* premature deactivation of the page.
*/
#define PMAP_TS_REFERENCED_MAX 5
void pmap_activate(struct thread *td);
void pmap_advise(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
int advice);
void pmap_align_superpage(vm_object_t, vm_ooffset_t, vm_offset_t *,
vm_size_t);
void pmap_clear_modify(vm_page_t m);
void pmap_copy(pmap_t, pmap_t, vm_offset_t, vm_size_t, vm_offset_t);
void pmap_copy_page(vm_page_t, vm_page_t);
void pmap_copy_pages(vm_page_t ma[], vm_offset_t a_offset,
vm_page_t mb[], vm_offset_t b_offset, int xfersize);
int pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m,
vm_prot_t prot, u_int flags, int8_t psind);
void pmap_enter_object(pmap_t pmap, vm_offset_t start,
vm_offset_t end, vm_page_t m_start, vm_prot_t prot);
void pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m,
vm_prot_t prot);
vm_paddr_t pmap_extract(pmap_t pmap, vm_offset_t va);
vm_page_t pmap_extract_and_hold(pmap_t pmap, vm_offset_t va,
vm_prot_t prot);
void pmap_growkernel(vm_offset_t);
void pmap_init(void);
boolean_t pmap_is_modified(vm_page_t m);
boolean_t pmap_is_prefaultable(pmap_t pmap, vm_offset_t va);
boolean_t pmap_is_referenced(vm_page_t m);
boolean_t pmap_is_valid_memattr(pmap_t, vm_memattr_t);
vm_offset_t pmap_map(vm_offset_t *, vm_paddr_t, vm_paddr_t, int);
int pmap_mincore(pmap_t pmap, vm_offset_t addr, vm_paddr_t *pap);
void pmap_object_init_pt(pmap_t pmap, vm_offset_t addr,
vm_object_t object, vm_pindex_t pindex, vm_size_t size);
boolean_t pmap_page_exists_quick(pmap_t pmap, vm_page_t m);
void pmap_page_init(vm_page_t m);
int pmap_page_wired_mappings(vm_page_t m);
int pmap_pinit(pmap_t);
void pmap_pinit0(pmap_t);
void pmap_protect(pmap_t, vm_offset_t, vm_offset_t, vm_prot_t);
void pmap_qenter(vm_offset_t, vm_page_t *, int);
void pmap_qremove(vm_offset_t, int);
vm_offset_t pmap_quick_enter_page(vm_page_t);
void pmap_quick_remove_page(vm_offset_t);
void pmap_release(pmap_t);
void pmap_remove(pmap_t, vm_offset_t, vm_offset_t);
void pmap_remove_all(vm_page_t m);
void pmap_remove_pages(pmap_t);
void pmap_remove_write(vm_page_t m);
void pmap_sync_icache(pmap_t, vm_offset_t, vm_size_t);
int pmap_ts_referenced(vm_page_t m);
void pmap_unwire(pmap_t pmap, vm_offset_t start, vm_offset_t end);
void pmap_zero_page(vm_page_t);
void pmap_zero_page_area(vm_page_t, int off, int size);
#define pmap_resident_count(pm) ((pm)->pm_stats.resident_count)
#define pmap_wired_count(pm) ((pm)->pm_stats.wired_count)
#endif /* _KERNEL */
#endif /* _PMAP_VM_ */
Reference in New Issue View Git Blame Copy Permalink