From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- kernel/locking/ww_rt_mutex.c | 101 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 kernel/locking/ww_rt_mutex.c (limited to 'kernel/locking/ww_rt_mutex.c') diff --git a/kernel/locking/ww_rt_mutex.c b/kernel/locking/ww_rt_mutex.c new file mode 100644 index 000000000..d1473c624 --- /dev/null +++ b/kernel/locking/ww_rt_mutex.c @@ -0,0 +1,101 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * rtmutex API + */ +#include +#include + +#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); -- cgit v1.2.3