1 1.5 riastrad /* $NetBSD: shrinker.h,v 1.5 2021/12/19 01:22:37 riastradh Exp $ */ 2 1.2 riastrad 3 1.2 riastrad /*- 4 1.2 riastrad * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 1.2 riastrad * All rights reserved. 6 1.2 riastrad * 7 1.2 riastrad * This code is derived from software contributed to The NetBSD Foundation 8 1.2 riastrad * by Taylor R. Campbell. 9 1.2 riastrad * 10 1.2 riastrad * Redistribution and use in source and binary forms, with or without 11 1.2 riastrad * modification, are permitted provided that the following conditions 12 1.2 riastrad * are met: 13 1.2 riastrad * 1. Redistributions of source code must retain the above copyright 14 1.2 riastrad * notice, this list of conditions and the following disclaimer. 15 1.2 riastrad * 2. Redistributions in binary form must reproduce the above copyright 16 1.2 riastrad * notice, this list of conditions and the following disclaimer in the 17 1.2 riastrad * documentation and/or other materials provided with the distribution. 18 1.2 riastrad * 19 1.2 riastrad * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 1.2 riastrad * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 1.2 riastrad * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 1.2 riastrad * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 1.2 riastrad * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 1.2 riastrad * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 1.2 riastrad * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 1.2 riastrad * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 1.2 riastrad * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 1.2 riastrad * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 1.2 riastrad * POSSIBILITY OF SUCH DAMAGE. 30 1.2 riastrad */ 31 1.2 riastrad 32 1.2 riastrad #ifndef _LINUX_SHRINKER_H_ 33 1.2 riastrad #define _LINUX_SHRINKER_H_ 34 1.2 riastrad 35 1.5 riastrad #include <uvm/uvm.h> 36 1.5 riastrad 37 1.2 riastrad struct shrink_control { 38 1.3 riastrad unsigned long nr_to_scan; 39 1.5 riastrad unsigned long nr_scanned; 40 1.2 riastrad }; 41 1.2 riastrad 42 1.2 riastrad struct shrinker { 43 1.3 riastrad int (*shrink)(struct shrinker *, struct shrink_control *); 44 1.3 riastrad unsigned long (*count_objects)(struct shrinker *, 45 1.3 riastrad struct shrink_control *); 46 1.3 riastrad unsigned long (*scan_objects)(struct shrinker *, 47 1.3 riastrad struct shrink_control *); 48 1.3 riastrad int seeks; 49 1.5 riastrad size_t batch; 50 1.2 riastrad }; 51 1.2 riastrad 52 1.4 riastrad #define SHRINK_STOP (~0UL) 53 1.4 riastrad 54 1.2 riastrad #define DEFAULT_SEEKS 2 /* XXX cargo-culted from Linux */ 55 1.2 riastrad 56 1.5 riastrad static inline int 57 1.2 riastrad register_shrinker(struct shrinker *shrinker __unused) 58 1.2 riastrad { 59 1.5 riastrad return 0; 60 1.2 riastrad } 61 1.2 riastrad 62 1.2 riastrad static inline void 63 1.2 riastrad unregister_shrinker(struct shrinker *shrinker __unused) 64 1.2 riastrad { 65 1.2 riastrad } 66 1.2 riastrad 67 1.5 riastrad static inline bool 68 1.5 riastrad current_is_kswapd(void) 69 1.5 riastrad { 70 1.5 riastrad return curlwp == uvm.pagedaemon_lwp; 71 1.5 riastrad } 72 1.5 riastrad 73 1.5 riastrad static inline size_t 74 1.5 riastrad get_nr_swap_pages(void) 75 1.5 riastrad { 76 1.5 riastrad return uvmexp.swpages; 77 1.5 riastrad } 78 1.5 riastrad 79 1.2 riastrad #endif /* _LINUX_SHRINKER_H_ */ 80