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
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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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18 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
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21 * CA 95054 USA or visit www.sun.com if you need additional information or
27 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
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30 * Copyright (c) 2011, 2012, Intel Corporation.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
37 #define DEBUG_SUBSYSTEM S_LNET
38 #include <linux/module.h>
39 #include <linux/kernel.h>
40 #include <linux/fs_struct.h>
41 #include <linux/sched.h>
43 #include "../../../include/linux/libcfs/libcfs.h"
45 #if defined(CONFIG_KGDB)
46 #include <linux/kgdb.h>
50 * wait_queue_t of Linux (version < 2.6.34) is a FIFO list for exclusively
51 * waiting threads, which is not always desirable because all threads will
52 * be waken up again and again, even user only needs a few of them to be
53 * active most time. This is not good for performance because cache can
54 * be polluted by different threads.
56 * LIFO list can resolve this problem because we always wakeup the most
57 * recent active thread by default.
59 * NB: please don't call non-exclusive & exclusive wait on the same
60 * waitq if add_wait_queue_exclusive_head is used.
63 add_wait_queue_exclusive_head(wait_queue_head_t *waitq, wait_queue_t *link)
67 spin_lock_irqsave(&waitq->lock, flags);
68 __add_wait_queue_exclusive(waitq, link);
69 spin_unlock_irqrestore(&waitq->lock, flags);
71 EXPORT_SYMBOL(add_wait_queue_exclusive_head);
74 cfs_block_allsigs(void)
79 spin_lock_irqsave(¤t->sighand->siglock, flags);
80 old = current->blocked;
81 sigfillset(¤t->blocked);
83 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
87 EXPORT_SYMBOL(cfs_block_allsigs);
89 sigset_t cfs_block_sigs(unsigned long sigs)
94 spin_lock_irqsave(¤t->sighand->siglock, flags);
95 old = current->blocked;
96 sigaddsetmask(¤t->blocked, sigs);
98 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
101 EXPORT_SYMBOL(cfs_block_sigs);
103 /* Block all signals except for the @sigs */
104 sigset_t cfs_block_sigsinv(unsigned long sigs)
109 spin_lock_irqsave(¤t->sighand->siglock, flags);
110 old = current->blocked;
111 sigaddsetmask(¤t->blocked, ~sigs);
113 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
117 EXPORT_SYMBOL(cfs_block_sigsinv);
120 cfs_restore_sigs(sigset_t old)
124 spin_lock_irqsave(¤t->sighand->siglock, flags);
125 current->blocked = old;
127 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
129 EXPORT_SYMBOL(cfs_restore_sigs);
132 cfs_signal_pending(void)
134 return signal_pending(current);
136 EXPORT_SYMBOL(cfs_signal_pending);
139 cfs_clear_sigpending(void)
143 spin_lock_irqsave(¤t->sighand->siglock, flags);
144 clear_tsk_thread_flag(current, TIF_SIGPENDING);
145 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
147 EXPORT_SYMBOL(cfs_clear_sigpending);