45 lines
1.6 KiB
Diff
45 lines
1.6 KiB
Diff
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From: Junxiao Chang <junxiao.chang@intel.com>
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Date: Mon, 20 Feb 2023 09:12:20 +0100
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Subject: [PATCH] softirq: Wake ktimers thread also in softirq.
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Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.11/older/patches-6.11-rt7.tar.xz
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If the hrtimer is raised while a softirq is processed then it does not
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wake the corresponding ktimers thread. This is due to the optimisation in the
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irq-exit path which is also used to wake the ktimers thread. For the other
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softirqs, this is okay because the additional softirq bits will be handled by
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the currently running softirq handler.
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The timer related softirq bits are added to a different variable and rely on
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the ktimers thread.
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As a consuequence the wake up of ktimersd is delayed until the next timer tick.
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Always wake the ktimers thread if a timer related softirq is pending.
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Reported-by: Peh, Hock Zhang <hock.zhang.peh@intel.com>
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Signed-off-by: Junxiao Chang <junxiao.chang@intel.com>
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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kernel/softirq.c | 11 +++++------
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1 file changed, 5 insertions(+), 6 deletions(-)
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--- a/kernel/softirq.c
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+++ b/kernel/softirq.c
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@@ -651,13 +651,12 @@ static inline void __irq_exit_rcu(void)
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#endif
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account_hardirq_exit(current);
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preempt_count_sub(HARDIRQ_OFFSET);
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- if (!in_interrupt()) {
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- if (local_softirq_pending())
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- invoke_softirq();
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+ if (!in_interrupt() && local_softirq_pending())
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+ invoke_softirq();
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- if (IS_ENABLED(CONFIG_PREEMPT_RT) && local_pending_timers())
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- wake_timersd();
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- }
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+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && local_pending_timers() &&
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+ !(in_nmi() | in_hardirq()))
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+ wake_timersd();
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tick_irq_exit();
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}
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