tegrakernel/kernel/kernel-4.9/rt-patches/0014-futex-rt_mutex-Restruc...

56 lines
2.1 KiB
Diff

From 930e844d958515d1a659d3f7d112d0001b28d2b0 Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz@infradead.org>
Date: Wed, 22 Mar 2017 11:35:57 +0100
Subject: [PATCH 014/365] futex,rt_mutex: Restructure
rt_mutex_finish_proxy_lock()
Upstream commit 38d589f2fd08f1296aea3ce62bebd185125c6d81
With the ultimate goal of keeping rt_mutex wait_list and futex_q waiters
consistent it's necessary to split 'rt_mutex_futex_lock()' into finer
parts, such that only the actual blocking can be done without hb->lock
held.
Split split_mutex_finish_proxy_lock() into two parts, one that does the
blocking and one that does remove_waiter() when the lock acquire failed.
When the rtmutex was acquired successfully the waiter can be removed in the
acquisiton path safely, since there is no concurrency on the lock owner.
This means that, except for futex_lock_pi(), all wait_list modifications
are done with both hb->lock and wait_lock held.
[bigeasy@linutronix.de: fix for futex_requeue_pi_signal_restart]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: xlpang@redhat.com
Cc: rostedt@goodmis.org
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: dvhart@infradead.org
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/20170322104152.001659630@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
kernel/locking/rtmutex_common.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
index b550e9d86b1f..8e81b17c0ee5 100644
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -113,6 +113,7 @@ extern int rt_mutex_wait_proxy_lock(struct rt_mutex *lock,
struct rt_mutex_waiter *waiter);
extern bool rt_mutex_cleanup_proxy_lock(struct rt_mutex *lock,
struct rt_mutex_waiter *waiter);
+
extern int rt_mutex_timed_futex_lock(struct rt_mutex *l, struct hrtimer_sleeper *to);
extern int rt_mutex_futex_trylock(struct rt_mutex *l);
--
2.28.0