1/* $OpenBSD: uvm_percpu.h,v 1.3 2024/05/01 12:54:27 mpi Exp $ */
2
3/*
4 * Copyright (c) 2024 Martin Pieuchot <mpi@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19#ifndef _UVM_UVM_PCPU_H_
20#define _UVM_UVM_PCPU_H_
21
22struct vm_page;
23
24/*
25 * The number of pages per magazine should be large enough to get rid of the
26 * contention in the pmemrange allocator during concurrent page faults and
27 * small enough to limit fragmentation.
28 */
29#define UVM_PMR_CACHEMAGSZ 8
30
31/*
32 * Magazine
33 */
34struct uvm_pmr_cache_item {
35 struct vm_page *upci_pages[UVM_PMR_CACHEMAGSZ];
36 int upci_npages; /* # of pages in magazine */
37};
38
39/*
40 * Per-CPU cache of physical pages.
41 */
42struct uvm_pmr_cache {
43 struct uvm_pmr_cache_item upc_magz[2]; /* magazines */
44 int upc_actv; /* index of active magazine */
45
46};
47
48#endif /* _UVM_UVM_PCPU_H_ */