From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Paul Thomas <pthomas8589@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
linux-rt-users <linux-rt-users@vger.kernel.org>,
dunc.mcphie@gmail.com, Anders Roxell <anders.roxell@linaro.org>
Subject: [PATCH RT] arm64: preempt: Check preemption level before looking at lazy-preempt
Date: Wed, 14 Aug 2019 18:17:09 +0200 [thread overview]
Message-ID: <20190814161709.cnlwxvycetlhe5no@linutronix.de> (raw)
In-Reply-To: <20190814112656.z3de2rgbqzpaquz5@linutronix.de>
Before evaluating the lazy-preempt state it must be ensure that the
preempt-count is zero.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
arch/arm64/include/asm/preempt.h | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/arm64/include/asm/preempt.h b/arch/arm64/include/asm/preempt.h
index 3bfad251203b5..ca1c6fe8dd347 100644
--- a/arch/arm64/include/asm/preempt.h
+++ b/arch/arm64/include/asm/preempt.h
@@ -73,6 +73,8 @@ static inline bool __preempt_count_dec_and_test(void)
if (!pc || !READ_ONCE(ti->preempt_count))
return true;
#ifdef CONFIG_PREEMPT_LAZY
+ if ((pc & ~PREEMPT_NEED_RESCHED))
+ return false;
if (current_thread_info()->preempt_lazy_count)
return false;
return test_thread_flag(TIF_NEED_RESCHED_LAZY);
--
2.23.0.rc1
next prev parent reply other threads:[~2019-08-14 16:17 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-12 11:18 poor cyclictest results with 5.0 series rt for arm64 Paul Thomas
[not found] ` <CAD56B7c2=95r7r-6tr0Mby8jSeuQPDNSd4LELnUw1LVRn9Rqew@mail.gmail.com>
2019-07-12 11:32 ` Paul Thomas
2019-07-16 20:24 ` Thomas Gleixner
2019-07-16 21:50 ` Paul Thomas
2019-07-16 23:14 ` Thomas Gleixner
2019-07-17 0:44 ` Paul Thomas
2019-07-17 8:03 ` Thomas Gleixner
2019-07-17 8:10 ` Thomas Gleixner
2019-07-17 9:02 ` Thomas Gleixner
2019-07-17 10:21 ` Thomas Gleixner
2019-07-17 22:28 ` Paul Thomas
2019-08-13 9:53 ` Sebastian Andrzej Siewior
2019-08-13 18:02 ` Paul Thomas
2019-08-14 11:26 ` Sebastian Andrzej Siewior
2019-08-14 16:17 ` Sebastian Andrzej Siewior [this message]
2019-08-14 16:17 ` [PATCH RT] x86: preempt: Check preemption level before looking at lazy-preempt Sebastian Andrzej Siewior
2019-08-14 17:04 ` poor cyclictest results with 5.0 series rt for arm64 Paul Thomas
2019-08-15 8:29 ` Sebastian Andrzej Siewior
2019-08-15 12:33 ` John Ogness
2019-08-15 13:30 ` Paul Thomas
2019-08-15 13:42 ` Sebastian Andrzej Siewior
2019-08-15 13:52 ` Paul Thomas
2019-08-15 14:19 ` Sebastian Andrzej Siewior
2019-08-15 15:12 ` Paul Thomas
2019-08-15 15:15 ` Sebastian Andrzej Siewior
2019-08-15 15:31 ` Paul Thomas
2019-08-15 18:00 ` Paul Thomas
2019-08-15 18:57 ` Sebastian Andrzej Siewior
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