From: Davidlohr Bueso <dave@stgolabs.net>
To: tglx@linutronix.de
Cc: mingo@redhat.com, peterz@infradead.org, dvhart@infradead.org,
dave@stgolabs.net, linux-kernel@vger.kernel.org,
Davidlohr Bueso <dbueso@suse.de>
Subject: [PATCH 2/4] kernel/futex: Make futex_wait_requeue_pi() only call fixup_owner()
Date: Fri, 26 Feb 2021 09:50:27 -0800 [thread overview]
Message-ID: <20210226175029.50335-2-dave@stgolabs.net> (raw)
In-Reply-To: <20210226175029.50335-1-dave@stgolabs.net>
A small cleanup that allows for fixup_pi_state_owner() only to be
called from fixup_owner(), and make the requeue_pi uniformly call
fixup_owner() regardless of the state in which the fixup is actually
needed. Of course this makes the caller's first pi_state->owner != current
check redundant, but that should't really matter.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
kernel/futex.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/kernel/futex.c b/kernel/futex.c
index db8002dbca7a..ee09995d707b 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -3241,15 +3241,14 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
* reference count.
*/
- /* Check if the requeue code acquired the second futex for us. */
+ /*
+ * Check if the requeue code acquired the second futex for us and do
+ * any pertinent fixup.
+ */
if (!q.rt_waiter) {
- /*
- * Got the lock. We might not be the anticipated owner if we
- * did a lock-steal - fix up the PI-state in that case.
- */
if (q.pi_state && (q.pi_state->owner != current)) {
spin_lock(q.lock_ptr);
- ret = fixup_pi_state_owner(uaddr2, &q, current);
+ ret = fixup_owner(uaddr2, &q, true);
/*
* Drop the reference to the pi state which
* the requeue_pi() code acquired for us.
--
2.26.2
next prev parent reply other threads:[~2021-02-26 17:52 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-26 17:50 [PATCH 1/4] kernel/futex: Kill rt_mutex_next_owner() Davidlohr Bueso
2021-02-26 17:50 ` Davidlohr Bueso [this message]
2021-03-11 18:24 ` [tip: locking/core] kernel/futex: Make futex_wait_requeue_pi() only call fixup_owner() tip-bot2 for Davidlohr Bueso
2021-02-26 17:50 ` [PATCH 3/4] kernel/futex: Move hb unlock out of unqueue_me_pi() Davidlohr Bueso
2021-03-11 18:24 ` [tip: locking/core] " tip-bot2 for Davidlohr Bueso
2021-02-26 17:50 ` [PATCH 4/4] kernel/futex: Explicitly document pi_lock for pi_state owner fixup Davidlohr Bueso
2021-03-11 18:24 ` [tip: locking/core] " tip-bot2 for Davidlohr Bueso
2021-03-01 15:19 ` [PATCH 1/4] kernel/futex: Kill rt_mutex_next_owner() Peter Zijlstra
2021-03-11 18:24 ` [tip: locking/core] " tip-bot2 for Davidlohr Bueso
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