xref: /freebsd/sys/contrib/openzfs/module/os/linux/spl/spl-shrinker.c (revision 61145dc2b94f12f6a47344fb9aac702321880e43)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
4  *  Copyright (C) 2007 The Regents of the University of California.
5  *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
6  *  Written by Brian Behlendorf <behlendorf1@llnl.gov>.
7  *  UCRL-CODE-235197
8  *
9  *  This file is part of the SPL, Solaris Porting Layer.
10  *
11  *  The SPL is free software; you can redistribute it and/or modify it
12  *  under the terms of the GNU General Public License as published by the
13  *  Free Software Foundation; either version 2 of the License, or (at your
14  *  option) any later version.
15  *
16  *  The SPL is distributed in the hope that it will be useful, but WITHOUT
17  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
18  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
19  *  for more details.
20  *
21  *  You should have received a copy of the GNU General Public License along
22  *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
23  *
24  *  Solaris Porting Layer (SPL) Shrinker Implementation.
25  */
26 
27 #include <sys/kmem.h>
28 #include <sys/shrinker.h>
29 
30 struct shrinker *
spl_register_shrinker(const char * name,spl_shrinker_cb countfunc,spl_shrinker_cb scanfunc,int seek_cost)31 spl_register_shrinker(const char *name, spl_shrinker_cb countfunc,
32     spl_shrinker_cb scanfunc, int seek_cost)
33 {
34 	struct shrinker *shrinker;
35 
36 	/* allocate shrinker */
37 #ifdef HAVE_SHRINKER_REGISTER
38 	/* 6.7: kernel will allocate the shrinker for us */
39 	shrinker = shrinker_alloc(0, name);
40 #else
41 	/* 4.4-6.6: we allocate the shrinker  */
42 	shrinker = kmem_zalloc(sizeof (struct shrinker), KM_SLEEP);
43 #endif
44 
45 	if (shrinker == NULL)
46 		return (NULL);
47 
48 	/* set callbacks */
49 	shrinker->count_objects = countfunc;
50 	shrinker->scan_objects = scanfunc;
51 
52 	/* set params */
53 	shrinker->seeks = seek_cost;
54 
55 	/* register with kernel */
56 #if defined(HAVE_SHRINKER_REGISTER)
57 	shrinker_register(shrinker);
58 #elif defined(HAVE_REGISTER_SHRINKER_VARARG)
59 	register_shrinker(shrinker, name);
60 #else
61 	register_shrinker(shrinker);
62 #endif
63 
64 	return (shrinker);
65 }
66 EXPORT_SYMBOL(spl_register_shrinker);
67 
68 void
spl_unregister_shrinker(struct shrinker * shrinker)69 spl_unregister_shrinker(struct shrinker *shrinker)
70 {
71 #if defined(HAVE_SHRINKER_REGISTER)
72 	shrinker_free(shrinker);
73 #else
74 	unregister_shrinker(shrinker);
75 	kmem_free(shrinker, sizeof (struct shrinker));
76 #endif
77 }
78 EXPORT_SYMBOL(spl_unregister_shrinker);
79