From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@kernel.org>,
Juri Lelli <juri.lelli@redhat.com>,
Steven Rostedt <rostedt@goodmis.org>,
Daniel Bristot de Oliveira <bristot@redhat.com>,
Will Deacon <will@kernel.org>, Waiman Long <longman@redhat.com>,
Boqun Feng <boqun.feng@gmail.com>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
Davidlohr Bueso <dave@stgolabs.net>
Subject: [patch 17/50] locking/rtmutex: Prepare RT rt_mutex_wake_q for RT locks
Date: Tue, 13 Jul 2021 17:11:11 +0200 [thread overview]
Message-ID: <20210713160747.601687056@linutronix.de> (raw)
In-Reply-To: 20210713151054.700719949@linutronix.de
From: Thomas Gleixner <tglx@linutronix.de>
Add a rtlock_task pointer to rt_mutex_wake_q which allows to handle the RT
specific wakeup for spin/rwlock waiters. The pointer is just consuming 4/8
bytes on stack so it is provided unconditionaly to avoid #ifdeffery all
over the place.
No functional change for non-RT enabled kernels.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
kernel/locking/rtmutex.c | 16 ++++++++++++++--
kernel/locking/rtmutex_common.h | 3 +++
2 files changed, 17 insertions(+), 2 deletions(-)
---
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -351,12 +351,24 @@ static __always_inline void rt_mutex_adj
static __always_inline void rt_mutex_wake_q_add(struct rt_mutex_wake_q_head *wqh,
struct rt_mutex_waiter *w)
{
- wake_q_add(&wqh->head, w->task);
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && w->wake_state != TASK_NORMAL) {
+ get_task_struct(w->task);
+ wqh->rtlock_task = w->task;
+ } else {
+ wake_q_add(&wqh->head, w->task);
+ }
}
static __always_inline void rt_mutex_wake_up_q(struct rt_mutex_wake_q_head *wqh)
{
- wake_up_q(&wqh->head);
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && wqh->rtlock_task) {
+ wake_up_state(wqh->rtlock_task, TASK_RTLOCK_WAIT);
+ put_task_struct(wqh->rtlock_task);
+ wqh->rtlock_task = NULL;
+ }
+
+ if (!wake_q_empty(&wqh->head))
+ wake_up_q(&wqh->head);
/* Pairs with preempt_disable() in mark_wakeup_next_waiter() */
preempt_enable();
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -43,14 +43,17 @@ struct rt_mutex_waiter {
* rt_mutex_wake_q_head - Wrapper around regular wake_q_head to support
* "sleeping" spinlocks on RT
* @head: The regular wake_q_head for sleeping lock variants
+ * @rtlock_task: Task pointer for RT lock (spin/rwlock) wakeups
*/
struct rt_mutex_wake_q_head {
struct wake_q_head head;
+ struct task_struct *rtlock_task;
};
#define DEFINE_RT_MUTEX_WAKE_Q_HEAD(name) \
struct rt_mutex_wake_q_head name = { \
.head = WAKE_Q_HEAD_INITIALIZER(name.head), \
+ .rtlock_task = NULL, \
}
/*
next prev parent reply other threads:[~2021-07-13 16:13 UTC|newest]
Thread overview: 77+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-13 15:10 [patch 00/50] locking, sched: The PREEMPT-RT locking infrastructure Thomas Gleixner
2021-07-13 15:10 ` [patch 01/50] sched: Split out the wakeup state check Thomas Gleixner
2021-07-13 15:10 ` [patch 02/50] sched: Introduce TASK_RTLOCK_WAIT Thomas Gleixner
2021-07-13 15:10 ` [patch 03/50] sched: Prepare for RT sleeping spin/rwlocks Thomas Gleixner
2021-07-13 19:52 ` Waiman Long
2021-07-14 23:20 ` Valentin Schneider
2021-07-15 9:27 ` Peter Zijlstra
2021-07-15 14:08 ` Valentin Schneider
2021-07-13 15:10 ` [patch 04/50] sched: Rework the __schedule() preempt argument Thomas Gleixner
2021-07-13 20:04 ` Waiman Long
2021-07-13 15:10 ` [patch 05/50] sched: Provide schedule point for RT locks Thomas Gleixner
2021-07-14 8:28 ` Peter Zijlstra
2021-07-14 9:49 ` Thomas Gleixner
2021-07-14 10:17 ` Peter Zijlstra
2021-07-14 11:32 ` Thomas Gleixner
2021-07-13 15:11 ` [patch 06/50] sched/wake_q: Provide WAKE_Q_HEAD_INITIALIZER Thomas Gleixner
2021-07-13 15:11 ` [patch 07/50] rtmutex: Convert macros to inlines Thomas Gleixner
2021-07-13 15:11 ` [patch 08/50] rtmutex: Switch to try_cmpxchg() Thomas Gleixner
2021-07-13 15:11 ` [patch 09/50] rtmutex: Split API and implementation Thomas Gleixner
2021-07-13 15:11 ` [patch 10/50] locking/rtmutex: Provide rt_mutex_slowlock_locked() Thomas Gleixner
2021-07-27 17:20 ` Valentin Schneider
2021-07-27 19:02 ` Thomas Gleixner
2021-07-13 15:11 ` [patch 11/50] locking/rtmutex: Provide lockdep less variants of rtmutex interfaces Thomas Gleixner
2021-07-13 15:11 ` [patch 12/50] locking: Add base code for RT rw_semaphore and rwlock Thomas Gleixner
2021-07-13 15:11 ` [patch 13/50] locking/rwsem: Add rtmutex based R/W semaphore implementation Thomas Gleixner
2021-07-13 15:11 ` [patch 14/50] locking/rtmutex: Add wake_state to rt_mutex_waiter Thomas Gleixner
2021-07-14 10:18 ` Peter Zijlstra
2021-07-14 11:33 ` Thomas Gleixner
2021-07-13 15:11 ` [patch 15/50] locking/rtmutex: Provide rt_mutex_wake_q and helpers Thomas Gleixner
2021-07-13 15:11 ` [patch 16/50] locking/rtmutex: Use rt_mutex_wake_q_head Thomas Gleixner
2021-07-14 8:55 ` Peter Zijlstra
2021-07-14 9:51 ` Thomas Gleixner
2021-07-13 15:11 ` Thomas Gleixner [this message]
2021-07-14 8:55 ` [patch 17/50] locking/rtmutex: Prepare RT rt_mutex_wake_q for RT locks Peter Zijlstra
2021-07-14 9:52 ` Thomas Gleixner
2021-07-13 15:11 ` [patch 18/50] locking/rtmutex: Guard regular sleeping locks specific functions Thomas Gleixner
2021-07-13 15:11 ` [patch 19/50] locking/spinlock: Split the lock types header Thomas Gleixner
2021-07-13 15:11 ` [patch 20/50] locking/rtmutex: Prevent future include recursion hell Thomas Gleixner
2021-07-13 15:11 ` [patch 21/50] locking/lockdep: Reduce includes in debug_locks.h Thomas Gleixner
2021-07-13 15:11 ` [patch 22/50] rbtree: Split out the rbtree type definitions Thomas Gleixner
2021-07-14 9:24 ` Peter Zijlstra
2021-07-14 9:31 ` Arnaldo
2021-07-13 15:11 ` [patch 23/50] locking/rtmutex: Include only rbtree types Thomas Gleixner
2021-07-13 15:11 ` [patch 24/50] locking/spinlock: Provide RT specific spinlock type Thomas Gleixner
2021-07-14 9:54 ` Peter Zijlstra
2021-07-14 10:07 ` [PATCH] media/atomisp: Use lockdep instead of *mutex_is_locked() Peter Zijlstra
2021-07-13 15:11 ` [patch 25/50] locking/spinlock: Provide RT variant header Thomas Gleixner
2021-07-13 15:11 ` [patch 26/50] locking/rtmutex: Provide the spin/rwlock core lock function Thomas Gleixner
2021-07-14 10:59 ` Peter Zijlstra
2021-07-13 15:11 ` [patch 27/50] locking/spinlock: Provide RT variant Thomas Gleixner
2021-07-14 11:25 ` Peter Zijlstra
2021-07-13 15:11 ` [patch 28/50] locking/rwlock: " Thomas Gleixner
2021-07-13 15:11 ` [patch 29/50] locking/mutex: Consolidate core headers Thomas Gleixner
2021-07-13 15:11 ` [patch 30/50] locking/mutex: Move waiter to core header Thomas Gleixner
2021-07-13 15:11 ` [patch 31/50] locking/ww_mutex: Move ww_mutex declarations into ww_mutex.h Thomas Gleixner
2021-07-13 15:11 ` [patch 32/50] locking/mutex: Make mutex::wait_lock raw Thomas Gleixner
2021-07-13 15:11 ` [patch 33/50] locking/mutex: Introduce _mutex_t Thomas Gleixner
2021-07-15 17:31 ` Peter Zijlstra
2021-07-13 15:11 ` [patch 34/50] locking/mutex: Rename the ww_mutex relevant functions Thomas Gleixner
2021-07-13 15:11 ` [patch 35/50] locking/ww_mutex: Switch to _mutex_t Thomas Gleixner
2021-07-13 15:11 ` [patch 36/50] locking/mutex: Replace struct mutex in core code Thomas Gleixner
2021-07-13 15:11 ` [patch 37/50] locking/mutex: Rearrange items in mutex.h Thomas Gleixner
2021-07-13 15:11 ` [patch 38/50] locking/mutex: Exclude non-ww_mutex API for RT Thomas Gleixner
2021-07-13 15:11 ` [patch 39/50] locking/rtmutex: Add mutex variant " Thomas Gleixner
2021-07-13 15:11 ` [patch 40/50] lib/test_lockup: Adapt to changed variables Thomas Gleixner
2021-07-13 15:11 ` [patch 41/50] futex: Validate waiter correctly in futex_proxy_trylock_atomic() Thomas Gleixner
2021-07-13 15:11 ` [patch 42/50] futex: Cleanup stale comments Thomas Gleixner
2021-07-28 23:28 ` André Almeida
2021-07-13 15:11 ` [patch 43/50] futex: Correct the number of requeued waiters for PI Thomas Gleixner
2021-07-13 15:11 ` [patch 44/50] futex: Restructure futex_requeue() Thomas Gleixner
2021-07-13 15:11 ` [patch 45/50] futex: Clarify comment in futex_requeue() Thomas Gleixner
2021-07-13 15:11 ` [patch 46/50] futex: Prevent requeue_pi() lock nesting issue on RT Thomas Gleixner
2021-07-13 15:11 ` [patch 47/50] rtmutex: Prevent lockdep false positive with PI futexes Thomas Gleixner
2021-07-13 15:11 ` [patch 48/50] preempt: Adjust PREEMPT_LOCK_OFFSET for RT Thomas Gleixner
2021-07-13 15:11 ` [patch 49/50] locking/rtmutex: Implement equal priority lock stealing Thomas Gleixner
2021-07-13 15:11 ` [patch 50/50] locking/rtmutex: Add adaptive spinwait mechanism Thomas Gleixner
2021-07-27 17:19 ` [patch 00/50] locking, sched: The PREEMPT-RT locking infrastructure Valentin Schneider
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