From 2408f7a3782a6bfa69a573f5408b3a9666db78ca Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sun, 15 Aug 2021 23:28:56 +0200 Subject: [PATCH] locking/ww_mutex: Add rt_mutex based lock type and accessors Provide the defines for RT mutex based ww_mutexes and fix up the debug logic so it's either enabled by DEBUG_MUTEXES or DEBUG_RT_MUTEXES on RT kernels. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20210815211304.908012566@linutronix.de --- include/linux/ww_mutex.h | 33 ++++++++++++++++++++++++--------- kernel/locking/ww_mutex.h | 6 +++--- 2 files changed, 27 insertions(+), 12 deletions(-) diff --git a/include/linux/ww_mutex.h b/include/linux/ww_mutex.h index 3438e302a52a..29db736af86d 100644 --- a/include/linux/ww_mutex.h +++ b/include/linux/ww_mutex.h @@ -18,11 +18,24 @@ #define __LINUX_WW_MUTEX_H #include +#include +#if defined(CONFIG_DEBUG_MUTEXES) || \ + (defined(CONFIG_PREEMPT_RT) && defined(CONFIG_DEBUG_RT_MUTEXES)) +#define DEBUG_WW_MUTEXES +#endif + +#ifndef CONFIG_PREEMPT_RT #define WW_MUTEX_BASE mutex #define ww_mutex_base_init(l,n,k) __mutex_init(l,n,k) #define ww_mutex_base_trylock(l) mutex_trylock(l) #define ww_mutex_base_is_locked(b) mutex_is_locked((b)) +#else +#define WW_MUTEX_BASE rt_mutex +#define ww_mutex_base_init(l,n,k) __rt_mutex_init(l,n,k) +#define ww_mutex_base_trylock(l) rt_mutex_trylock(l) +#define ww_mutex_base_is_locked(b) rt_mutex_base_is_locked(&(b)->rtmutex) +#endif struct ww_class { atomic_long_t stamp; @@ -36,7 +49,7 @@ struct ww_class { struct ww_mutex { struct WW_MUTEX_BASE base; struct ww_acquire_ctx *ctx; -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES struct ww_class *ww_class; #endif }; @@ -47,10 +60,10 @@ struct ww_acquire_ctx { unsigned int acquired; unsigned short wounded; unsigned short is_wait_die; -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES unsigned int done_acquire; struct ww_class *ww_class; - struct ww_mutex *contending_lock; + void *contending_lock; #endif #ifdef CONFIG_DEBUG_LOCK_ALLOC struct lockdep_map dep_map; @@ -89,7 +102,7 @@ static inline void ww_mutex_init(struct ww_mutex *lock, { ww_mutex_base_init(&lock->base, ww_class->mutex_name, &ww_class->mutex_key); lock->ctx = NULL; -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES lock->ww_class = ww_class; #endif } @@ -126,7 +139,7 @@ static inline void ww_acquire_init(struct ww_acquire_ctx *ctx, ctx->acquired = 0; ctx->wounded = false; ctx->is_wait_die = ww_class->is_wait_die; -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES ctx->ww_class = ww_class; ctx->done_acquire = 0; ctx->contending_lock = NULL; @@ -156,7 +169,7 @@ static inline void ww_acquire_init(struct ww_acquire_ctx *ctx, */ static inline void ww_acquire_done(struct ww_acquire_ctx *ctx) { -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES lockdep_assert_held(ctx); DEBUG_LOCKS_WARN_ON(ctx->done_acquire); @@ -176,7 +189,7 @@ static inline void ww_acquire_fini(struct ww_acquire_ctx *ctx) #ifdef CONFIG_DEBUG_LOCK_ALLOC mutex_release(&ctx->dep_map, _THIS_IP_); #endif -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES DEBUG_LOCKS_WARN_ON(ctx->acquired); if (!IS_ENABLED(CONFIG_PROVE_LOCKING)) /* @@ -282,7 +295,7 @@ static inline void ww_mutex_lock_slow(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) { int ret; -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES DEBUG_LOCKS_WARN_ON(!ctx->contending_lock); #endif ret = ww_mutex_lock(lock, ctx); @@ -318,7 +331,7 @@ static inline int __must_check ww_mutex_lock_slow_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) { -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES DEBUG_LOCKS_WARN_ON(!ctx->contending_lock); #endif return ww_mutex_lock_interruptible(lock, ctx); @@ -348,7 +361,9 @@ static inline int __must_check ww_mutex_trylock(struct ww_mutex *lock) */ static inline void ww_mutex_destroy(struct ww_mutex *lock) { +#ifndef CONFIG_PREEMPT_RT mutex_destroy(&lock->base); +#endif } /** diff --git a/kernel/locking/ww_mutex.h b/kernel/locking/ww_mutex.h index 2dce4f0b0d1c..56f139201f24 100644 --- a/kernel/locking/ww_mutex.h +++ b/kernel/locking/ww_mutex.h @@ -180,7 +180,7 @@ static inline void lockdep_assert_wait_lock_held(struct rt_mutex *lock) static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww, struct ww_acquire_ctx *ww_ctx) { -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES /* * If this WARN_ON triggers, you used ww_mutex_lock to acquire, * but released with a normal mutex_unlock in this call. @@ -413,7 +413,7 @@ static __always_inline int __ww_mutex_kill(struct MUTEX *lock, struct ww_acquire_ctx *ww_ctx) { if (ww_ctx->acquired > 0) { -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES struct ww_mutex *ww; ww = container_of(lock, struct ww_mutex, base); @@ -559,7 +559,7 @@ __ww_mutex_add_waiter(struct MUTEX_WAITER *waiter, static inline void __ww_mutex_unlock(struct ww_mutex *lock) { if (lock->ctx) { -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES DEBUG_LOCKS_WARN_ON(!lock->ctx->acquired); #endif if (lock->ctx->acquired > 0)