// 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);