1
2 /*--------------------------------------------------------------------*/
3 /*--- Generic scheduler lock implementation sched-lock-generic.c ---*/
4 /*--- ---*/
5 /*--- This implementation does not guarantee fair scheduling on ---*/
6 /*--- multicore systems but is sufficient to make the Valgrind ---*/
7 /*--- scheduler work reasonably. ---*/
8 /*--------------------------------------------------------------------*/
9
10 /*
11 This file is part of Valgrind, a dynamic binary instrumentation
12 framework.
13
14 Copyright (C) 2011-2017 Bart Van Assche <bvanassche@acm.org>.
15
16 This program is free software; you can redistribute it and/or
17 modify it under the terms of the GNU General Public License as
18 published by the Free Software Foundation; either version 2 of the
19 License, or (at your option) any later version.
20
21 This program is distributed in the hope that it will be useful, but
22 WITHOUT ANY WARRANTY; without even the implied warranty of
23 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
24 General Public License for more details.
25
26 You should have received a copy of the GNU General Public License
27 along with this program; if not, write to the Free Software
28 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
29 02111-1307, USA.
30
31 The GNU General Public License is contained in the file COPYING.
32 */
33
34 #include "pub_core_basics.h"
35 #include "pub_core_mallocfree.h"
36 #include "priv_sema.h"
37 #include "priv_sched-lock.h"
38 #include "priv_sched-lock-impl.h"
39
40 struct sched_lock {
41 vg_sema_t sema;
42 };
43
get_sched_lock_name(void)44 static const HChar *get_sched_lock_name(void)
45 {
46 return "generic";
47 }
48
create_sched_lock(void)49 static struct sched_lock *create_sched_lock(void)
50 {
51 struct sched_lock *p;
52
53 p = VG_(malloc)("sched_lock", sizeof(*p));
54 ML_(sema_init)(&p->sema);
55 return p;
56 }
57
destroy_sched_lock(struct sched_lock * p)58 static void destroy_sched_lock(struct sched_lock *p)
59 {
60 ML_(sema_deinit)(&p->sema);
61 VG_(free)(p);
62 }
63
get_sched_lock_owner(struct sched_lock * p)64 static int get_sched_lock_owner(struct sched_lock *p)
65 {
66 return p->sema.owner_lwpid;
67 }
68
acquire_sched_lock(struct sched_lock * p)69 static void acquire_sched_lock(struct sched_lock *p)
70 {
71 ML_(sema_down)(&p->sema, False);
72 }
73
release_sched_lock(struct sched_lock * p)74 static void release_sched_lock(struct sched_lock *p)
75 {
76 ML_(sema_up)(&p->sema, False);
77 }
78
79 const struct sched_lock_ops ML_(generic_sched_lock_ops) = {
80 .get_sched_lock_name = get_sched_lock_name,
81 .create_sched_lock = create_sched_lock,
82 .destroy_sched_lock = destroy_sched_lock,
83 .get_sched_lock_owner = get_sched_lock_owner,
84 .acquire_sched_lock = acquire_sched_lock,
85 .release_sched_lock = release_sched_lock,
86 };
87