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From: Henrik Austad <henrik@austad.us>
To: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	stable@vger.kernel.org, Henrik Austad <haustad@cisco.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Peter Zijlstra <peterz@infradead.org>,
	Darren Hart <darren@dvhart.com>,
	Davidlohr Bueso <dave@stgolabs.net>,
	Bhuvanesh_Surachari@mentor.com, Andy Lowe <Andy_Lowe@mentor.com>
Subject: [PATCH 09/17] futex: Rename free_pi_state() to put_pi_state()
Date: Fri,  9 Nov 2018 11:07:37 +0100	[thread overview]
Message-ID: <1541758065-10952-10-git-send-email-henrik@austad.us> (raw)
In-Reply-To: <1541758065-10952-1-git-send-email-henrik@austad.us>

From: Thomas Gleixner <tglx@linutronix.de>

commit 29e9ee5d48c35d6cf8afe09bdf03f77125c9ac11 upstream.

free_pi_state() is confusing as it is in fact only freeing/caching the
pi state when the last reference is gone. Rename it to put_pi_state()
which reflects better what it is doing.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <darren@dvhart.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Bhuvanesh_Surachari@mentor.com
Cc: Andy Lowe <Andy_Lowe@mentor.com>
Link: http://lkml.kernel.org/r/20151219200607.259636467@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Henrik Austad <haustad@cisco.com>
---
 kernel/futex.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/kernel/futex.c b/kernel/futex.c
index 91acb65..09f698a 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -815,9 +815,12 @@ static void get_pi_state(struct futex_pi_state *pi_state)
 }
 
 /*
+ * Drops a reference to the pi_state object and frees or caches it
+ * when the last reference is gone.
+ *
  * Must be called with the hb lock held.
  */
-static void free_pi_state(struct futex_pi_state *pi_state)
+static void put_pi_state(struct futex_pi_state *pi_state)
 {
 	if (!pi_state)
 		return;
@@ -1959,7 +1962,7 @@ retry_private:
 		case 0:
 			break;
 		case -EFAULT:
-			free_pi_state(pi_state);
+			put_pi_state(pi_state);
 			pi_state = NULL;
 			double_unlock_hb(hb1, hb2);
 			hb_waiters_dec(hb2);
@@ -1976,7 +1979,7 @@ retry_private:
 			 *   exit to complete.
 			 * - The user space value changed.
 			 */
-			free_pi_state(pi_state);
+			put_pi_state(pi_state);
 			pi_state = NULL;
 			double_unlock_hb(hb1, hb2);
 			hb_waiters_dec(hb2);
@@ -2049,7 +2052,7 @@ retry_private:
 			} else if (ret) {
 				/* -EDEADLK */
 				this->pi_state = NULL;
-				free_pi_state(pi_state);
+				put_pi_state(pi_state);
 				goto out_unlock;
 			}
 		}
@@ -2058,7 +2061,7 @@ retry_private:
 	}
 
 out_unlock:
-	free_pi_state(pi_state);
+	put_pi_state(pi_state);
 	double_unlock_hb(hb1, hb2);
 	wake_up_q(&wake_q);
 	hb_waiters_dec(hb2);
@@ -2211,7 +2214,7 @@ static void unqueue_me_pi(struct futex_q *q)
 	__unqueue_futex(q);
 
 	BUG_ON(!q->pi_state);
-	free_pi_state(q->pi_state);
+	put_pi_state(q->pi_state);
 	q->pi_state = NULL;
 
 	spin_unlock(q->lock_ptr);
@@ -2993,7 +2996,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
 			 * Drop the reference to the pi state which
 			 * the requeue_pi() code acquired for us.
 			 */
-			free_pi_state(q.pi_state);
+			put_pi_state(q.pi_state);
 			spin_unlock(q.lock_ptr);
 		}
 	} else {
-- 
2.7.4


  parent reply	other threads:[~2018-11-09 10:09 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-11-09 10:07 [PATCH 00/17] Backport rt/deadline crash and the ardous story of FUTEX_UNLOCK_PI to 4.4 Henrik Austad
2018-11-09 10:07 ` [PATCH 01/17] futex: Cleanup variable names for futex_top_waiter() Henrik Austad
2018-11-09 10:07 ` [PATCH 02/17] futex: Use smp_store_release() in mark_wake_futex() Henrik Austad
2018-11-09 10:07 ` [PATCH 03/17] futex: Remove rt_mutex_deadlock_account_*() Henrik Austad
2018-11-09 10:07 ` [PATCH 04/17] rtmutex: Make wait_lock irq safe Henrik Austad
2018-11-09 10:07 ` [PATCH 05/17] futex,rt_mutex: Provide futex specific rt_mutex API Henrik Austad
2018-11-09 10:07 ` [PATCH 06/17] futex: Change locking rules Henrik Austad
2018-11-09 10:07 ` [PATCH 07/17] futex: Cleanup refcounting Henrik Austad
2018-11-09 10:07 ` [PATCH 08/17] futex: Rework inconsistent rt_mutex/futex_q state Henrik Austad
2018-11-09 10:07 ` Henrik Austad [this message]
2018-11-09 10:07 ` [PATCH 10/17] futex: Pull rt_mutex_futex_unlock() out from under hb->lock Henrik Austad
2018-11-09 10:07 ` [PATCH 11/17] futex,rt_mutex: Introduce rt_mutex_init_waiter() Henrik Austad
2018-11-09 10:07 ` [PATCH 12/17] futex,rt_mutex: Restructure rt_mutex_finish_proxy_lock() Henrik Austad
2018-11-09 10:07 ` [PATCH 13/17] futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock() Henrik Austad
2018-11-09 10:07 ` [PATCH 14/17] futex: Futex_unlock_pi() determinism Henrik Austad
2018-11-09 10:07 ` [PATCH 15/17] futex: Drop hb->lock before enqueueing on the rtmutex Henrik Austad
2018-11-09 10:07 ` [PATCH 16/17] rtmutex: Deboost before waking up the top waiter Henrik Austad
2018-11-09 10:07 ` [PATCH 17/17] sched/rtmutex/deadline: Fix a PI crash for deadline tasks Henrik Austad
2018-11-09 10:35 ` [PATCH 00/17] Backport rt/deadline crash and the ardous story of FUTEX_UNLOCK_PI to 4.4 Henrik Austad
2018-11-19 11:27   ` Henrik Austad
2018-12-14  7:18     ` Greg Kroah-Hartman
2018-12-14  7:36       ` Henrik Austad

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