42 lines
1.3 KiB
Diff
42 lines
1.3 KiB
Diff
From 6ad06036f0ac7e3ff7b58c3ef2c7164d798a59ff Mon Sep 17 00:00:00 2001
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From: Thomas Gleixner <tglx@linutronix.de>
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Date: Tue, 13 Dec 2011 21:42:19 +0100
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Subject: [PATCH 155/278] sched: ttwu: Return success when only changing the
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saved_state value
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When a task blocks on a rt lock, it saves the current state in
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p->saved_state, so a lock related wake up will not destroy the
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original state.
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When a real wakeup happens, while the task is running due to a lock
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wakeup already, we update p->saved_state to TASK_RUNNING, but we do
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not return success, which might cause another wakeup in the waitqueue
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code and the task remains in the waitqueue list. Return success in
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that case as well.
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Cc: stable-rt@vger.kernel.org
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---
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kernel/sched.c | 4 +++-
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1 file changed, 3 insertions(+), 1 deletion(-)
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diff --git a/kernel/sched.c b/kernel/sched.c
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index ae726d7..425a466 100644
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--- a/kernel/sched.c
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+++ b/kernel/sched.c
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@@ -2830,8 +2830,10 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
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* if the wakeup condition is true.
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*/
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if (!(wake_flags & WF_LOCK_SLEEPER)) {
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- if (p->saved_state & state)
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+ if (p->saved_state & state) {
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p->saved_state = TASK_RUNNING;
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+ success = 1;
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+ }
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}
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goto out;
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}
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--
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1.7.10
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