From 9934ccc75cec2bafac552c2130835630530c4f7e Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sun, 15 Aug 2021 23:28:49 +0200 Subject: [PATCH] locking/ww_mutex: Abstract out mutex accessors Move the mutex related access from various ww_mutex functions into helper functions so they can be substituted for rtmutex based ww_mutex later. 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/20210815211304.622477030@linutronix.de --- kernel/locking/ww_mutex.h | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/kernel/locking/ww_mutex.h b/kernel/locking/ww_mutex.h index f5aaf2f..842dbed 100644 --- a/kernel/locking/ww_mutex.h +++ b/kernel/locking/ww_mutex.h @@ -53,6 +53,18 @@ __ww_waiter_add(struct mutex *lock, struct mutex_waiter *waiter, struct mutex_wa __mutex_add_waiter(lock, waiter, p); } +static inline struct task_struct * +__ww_mutex_owner(struct mutex *lock) +{ + return __mutex_owner(lock); +} + +static inline bool +__ww_mutex_has_waiters(struct mutex *lock) +{ + return atomic_long_read(&lock->owner) & MUTEX_FLAG_WAITERS; +} + /* * Wait-Die: * The newer transactions are killed when: @@ -157,7 +169,7 @@ static bool __ww_mutex_wound(struct mutex *lock, struct ww_acquire_ctx *ww_ctx, struct ww_acquire_ctx *hold_ctx) { - struct task_struct *owner = __mutex_owner(lock); + struct task_struct *owner = __ww_mutex_owner(lock); lockdep_assert_held(&lock->wait_lock); @@ -253,7 +265,7 @@ ww_mutex_set_context_fastpath(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) * __ww_mutex_add_waiter() and makes sure we either observe ww->ctx * and/or !empty list. */ - if (likely(!(atomic_long_read(&lock->base.owner) & MUTEX_FLAG_WAITERS))) + if (likely(!__ww_mutex_has_waiters(&lock->base))) return; /* -- 2.7.4