2 * Copyright (c) 1997 John Birrell <jb@cimlogic.com.au>.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the author nor the names of any co-contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 #include <sys/types.h>
32 #include <machine/atomic.h>
33 #include <machine/tls.h>
35 #include <libc_private.h>
38 #include "thr_private.h"
40 #define MAX_SPINLOCKS 256
43 * These data structures are used to trace all spinlocks
46 struct spinlock_extra
{
50 static umtx_t spinlock_static_lock
;
51 static struct spinlock_extra extra
[MAX_SPINLOCKS
];
52 static int spinlock_count
;
53 static int initialized
;
55 static void init_spinlock(spinlock_t
*lck
);
58 * These are for compatability only. Spinlocks of this type
63 _spinunlock(spinlock_t
*lck
)
65 struct pthread
*curthread
= tls_get_curthread();
67 THR_UMTX_UNLOCK(curthread
, (volatile umtx_t
*)&lck
->access_lock
);
71 _spinlock(spinlock_t
*lck
)
73 struct pthread
*curthread
;
76 PANIC("Spinlock called when not threaded.");
78 PANIC("Spinlocks not initialized.");
79 if (lck
->fname
== NULL
)
82 curthread
= tls_get_curthread();
83 THR_UMTX_LOCK(curthread
, (volatile umtx_t
*)&lck
->access_lock
);
87 * Returns 0 on success, else EBUSY
90 _spintrylock(spinlock_t
*lck
)
92 struct pthread
*curthread
;
95 PANIC("Spinlock called when not threaded.");
97 PANIC("Spinlocks not initialized.");
98 if (lck
->fname
== NULL
)
101 curthread
= tls_get_curthread();
102 return(THR_UMTX_TRYLOCK(curthread
,
103 (volatile umtx_t
*)&lck
->access_lock
));
107 _spinlock_debug(spinlock_t
*lck
, char *fname __unused
, int lineno __unused
)
113 init_spinlock(spinlock_t
*lck
)
115 static int count
= 0;
116 struct pthread
*curthread
= tls_get_curthread();
118 THR_UMTX_LOCK(curthread
, &spinlock_static_lock
);
119 if ((lck
->fname
== NULL
) && (spinlock_count
< MAX_SPINLOCKS
)) {
120 lck
->fname
= (char *)&extra
[spinlock_count
];
121 extra
[spinlock_count
].owner
= lck
;
124 THR_UMTX_UNLOCK(curthread
, &spinlock_static_lock
);
125 if (lck
->fname
== NULL
&& ++count
< 5)
126 stderr_debug("Warning: exceeded max spinlocks");
130 _thr_spinlock_init(void)
134 _thr_umtx_init(&spinlock_static_lock
);
135 if (initialized
!= 0) {
137 * called after fork() to reset state of libc spin locks,
138 * it is not quite right since libc may be in inconsistent
139 * state, resetting the locks to allow current thread to be
140 * able to hold them may not help things too much, but
141 * anyway, we do our best.
142 * it is better to do pthread_atfork in libc.
144 for (i
= 0; i
< spinlock_count
; i
++)
145 _thr_umtx_init((volatile umtx_t
*)
146 &extra
[i
].owner
->access_lock
);