1 // SPDX-License-Identifier: GPL-2.0-only 1 // SPDX-License-Identifier: GPL-2.0-only
2 /* 2 /*
3 * rtmutex API 3 * rtmutex API
4 */ 4 */
5 #include <linux/spinlock.h> 5 #include <linux/spinlock.h>
6 #include <linux/export.h> 6 #include <linux/export.h>
7 7
8 #define RT_MUTEX_BUILD_MUTEX 8 #define RT_MUTEX_BUILD_MUTEX
9 #define WW_RT 9 #define WW_RT
10 #include "rtmutex.c" 10 #include "rtmutex.c"
11 11
12 int ww_mutex_trylock(struct ww_mutex *lock, st 12 int ww_mutex_trylock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx)
13 { 13 {
14 struct rt_mutex *rtm = &lock->base; 14 struct rt_mutex *rtm = &lock->base;
15 15
16 if (!ww_ctx) 16 if (!ww_ctx)
17 return rt_mutex_trylock(rtm); 17 return rt_mutex_trylock(rtm);
18 18
19 /* 19 /*
20 * Reset the wounded flag after a kill 20 * Reset the wounded flag after a kill. No other process can
21 * race and wound us here, since they 21 * race and wound us here, since they can't have a valid owner
22 * pointer if we don't have any locks 22 * pointer if we don't have any locks held.
23 */ 23 */
24 if (ww_ctx->acquired == 0) 24 if (ww_ctx->acquired == 0)
25 ww_ctx->wounded = 0; 25 ww_ctx->wounded = 0;
26 26
27 if (__rt_mutex_trylock(&rtm->rtmutex)) 27 if (__rt_mutex_trylock(&rtm->rtmutex)) {
28 ww_mutex_set_context_fastpath( 28 ww_mutex_set_context_fastpath(lock, ww_ctx);
29 mutex_acquire_nest(&rtm->dep_m 29 mutex_acquire_nest(&rtm->dep_map, 0, 1, &ww_ctx->dep_map, _RET_IP_);
30 return 1; 30 return 1;
31 } 31 }
32 32
33 return 0; 33 return 0;
34 } 34 }
35 EXPORT_SYMBOL(ww_mutex_trylock); 35 EXPORT_SYMBOL(ww_mutex_trylock);
36 36
37 static int __sched 37 static int __sched
38 __ww_rt_mutex_lock(struct ww_mutex *lock, stru 38 __ww_rt_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx,
39 unsigned int state, unsigne 39 unsigned int state, unsigned long ip)
40 { 40 {
41 struct lockdep_map __maybe_unused *nes 41 struct lockdep_map __maybe_unused *nest_lock = NULL;
42 struct rt_mutex *rtm = &lock->base; 42 struct rt_mutex *rtm = &lock->base;
43 int ret; 43 int ret;
44 44
45 might_sleep(); 45 might_sleep();
46 46
47 if (ww_ctx) { 47 if (ww_ctx) {
48 if (unlikely(ww_ctx == READ_ON 48 if (unlikely(ww_ctx == READ_ONCE(lock->ctx)))
49 return -EALREADY; 49 return -EALREADY;
50 50
51 /* 51 /*
52 * Reset the wounded flag afte 52 * Reset the wounded flag after a kill. No other process can
53 * race and wound us here, sin 53 * race and wound us here, since they can't have a valid owner
54 * pointer if we don't have an 54 * pointer if we don't have any locks held.
55 */ 55 */
56 if (ww_ctx->acquired == 0) 56 if (ww_ctx->acquired == 0)
57 ww_ctx->wounded = 0; 57 ww_ctx->wounded = 0;
58 58
59 #ifdef CONFIG_DEBUG_LOCK_ALLOC 59 #ifdef CONFIG_DEBUG_LOCK_ALLOC
60 nest_lock = &ww_ctx->dep_map; 60 nest_lock = &ww_ctx->dep_map;
61 #endif 61 #endif
62 } 62 }
63 mutex_acquire_nest(&rtm->dep_map, 0, 0 63 mutex_acquire_nest(&rtm->dep_map, 0, 0, nest_lock, ip);
64 64
65 if (likely(rt_mutex_try_acquire(&rtm-> 65 if (likely(rt_mutex_try_acquire(&rtm->rtmutex))) {
66 if (ww_ctx) 66 if (ww_ctx)
67 ww_mutex_set_context_f 67 ww_mutex_set_context_fastpath(lock, ww_ctx);
68 return 0; 68 return 0;
69 } 69 }
70 70
71 ret = rt_mutex_slowlock(&rtm->rtmutex, 71 ret = rt_mutex_slowlock(&rtm->rtmutex, ww_ctx, state);
72 72
73 if (ret) 73 if (ret)
74 mutex_release(&rtm->dep_map, i 74 mutex_release(&rtm->dep_map, ip);
75 return ret; 75 return ret;
76 } 76 }
77 77
78 int __sched 78 int __sched
79 ww_mutex_lock(struct ww_mutex *lock, struct ww 79 ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
80 { 80 {
81 return __ww_rt_mutex_lock(lock, ctx, T 81 return __ww_rt_mutex_lock(lock, ctx, TASK_UNINTERRUPTIBLE, _RET_IP_);
82 } 82 }
83 EXPORT_SYMBOL(ww_mutex_lock); 83 EXPORT_SYMBOL(ww_mutex_lock);
84 84
85 int __sched 85 int __sched
86 ww_mutex_lock_interruptible(struct ww_mutex *l 86 ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
87 { 87 {
88 return __ww_rt_mutex_lock(lock, ctx, T 88 return __ww_rt_mutex_lock(lock, ctx, TASK_INTERRUPTIBLE, _RET_IP_);
89 } 89 }
90 EXPORT_SYMBOL(ww_mutex_lock_interruptible); 90 EXPORT_SYMBOL(ww_mutex_lock_interruptible);
91 91
92 void __sched ww_mutex_unlock(struct ww_mutex * 92 void __sched ww_mutex_unlock(struct ww_mutex *lock)
93 { 93 {
94 struct rt_mutex *rtm = &lock->base; 94 struct rt_mutex *rtm = &lock->base;
95 95
96 __ww_mutex_unlock(lock); 96 __ww_mutex_unlock(lock);
97 97
98 mutex_release(&rtm->dep_map, _RET_IP_) 98 mutex_release(&rtm->dep_map, _RET_IP_);
99 __rt_mutex_unlock(&rtm->rtmutex); 99 __rt_mutex_unlock(&rtm->rtmutex);
100 } 100 }
101 EXPORT_SYMBOL(ww_mutex_unlock); 101 EXPORT_SYMBOL(ww_mutex_unlock);
102 102
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