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// SPDX-License-Identifier: GPL-2.0-only
/*
* rtmutex API
*/
#include <linux/spinlock.h>
#include <linux/export.h>
#define RT_MUTEX_BUILD_MUTEX
#define WW_RT
#include "rtmutex.c"
int ww_mutex_trylock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx)
{
struct rt_mutex *rtm = &lock->base;
if (!ww_ctx)
return rt_mutex_trylock(rtm);
/*
* Reset the wounded flag after a kill. No other process can
* race and wound us here, since they can't have a valid owner
* pointer if we don't have any locks held.
*/
if (ww_ctx->acquired == 0)
ww_ctx->wounded = 0;
if (__rt_mutex_trylock(&rtm->rtmutex)) {
ww_mutex_set_context_fastpath(lock, ww_ctx);
mutex_acquire_nest(&rtm->dep_map, 0, 1, &ww_ctx->dep_map, _RET_IP_);
return 1;
}
return 0;
}
EXPORT_SYMBOL(ww_mutex_trylock);
static int __sched
__ww_rt_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx,
unsigned int state, unsigned long ip)
{
struct lockdep_map __maybe_unused *nest_lock = NULL;
struct rt_mutex *rtm = &lock->base;
int ret;
might_sleep();
if (ww_ctx) {
if (unlikely(ww_ctx == READ_ONCE(lock->ctx)))
return -EALREADY;
/*
* Reset the wounded flag after a kill. No other process can
* race and wound us here, since they can't have a valid owner
* pointer if we don't have any locks held.
*/
if (ww_ctx->acquired == 0)
ww_ctx->wounded = 0;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
nest_lock = &ww_ctx->dep_map;
#endif
}
mutex_acquire_nest(&rtm->dep_map, 0, 0, nest_lock, ip);
if (likely(rt_mutex_cmpxchg_acquire(&rtm->rtmutex, NULL, current))) {
if (ww_ctx)
ww_mutex_set_context_fastpath(lock, ww_ctx);
return 0;
}
ret = rt_mutex_slowlock(&rtm->rtmutex, ww_ctx, state);
if (ret)
mutex_release(&rtm->dep_map, ip);
return ret;
}
int __sched
ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
{
return __ww_rt_mutex_lock(lock, ctx, TASK_UNINTERRUPTIBLE, _RET_IP_);
}
EXPORT_SYMBOL(ww_mutex_lock);
int __sched
ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
{
return __ww_rt_mutex_lock(lock, ctx, TASK_INTERRUPTIBLE, _RET_IP_);
}
EXPORT_SYMBOL(ww_mutex_lock_interruptible);
void __sched ww_mutex_unlock(struct ww_mutex *lock)
{
struct rt_mutex *rtm = &lock->base;
__ww_mutex_unlock(lock);
mutex_release(&rtm->dep_map, _RET_IP_);
__rt_mutex_unlock(&rtm->rtmutex);
}
EXPORT_SYMBOL(ww_mutex_unlock);
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