4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
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17 * version 2 along with this program; If not, see
18 * http://www.gnu.org/licenses/gpl-2.0.html
23 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Use is subject to license terms.
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30 * libcfs/include/libcfs/libcfs_prim.h
36 #ifndef __LIBCFS_PRIM_H__
37 #define __LIBCFS_PRIM_H__
39 #include <linux/sched.h>
44 #if BITS_PER_LONG == 32
45 /* limit to lowmem on 32-bit systems */
46 # define NUM_CACHEPAGES \
47 min(totalram_pages, 1UL << (30 - PAGE_SHIFT) * 3 / 4)
49 # define NUM_CACHEPAGES totalram_pages
52 static inline unsigned int memory_pressure_get(void)
54 return current->flags & PF_MEMALLOC;
57 static inline void memory_pressure_set(void)
59 current->flags |= PF_MEMALLOC;
62 static inline void memory_pressure_clr(void)
64 current->flags &= ~PF_MEMALLOC;
67 static inline int cfs_memory_pressure_get_and_set(void)
69 int old = memory_pressure_get();
72 memory_pressure_set();
76 static inline void cfs_memory_pressure_restore(int old)
79 memory_pressure_set();
81 memory_pressure_clr();