diff options
| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2016-01-20 15:39:05 +0100 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2016-03-02 09:50:59 -0500 |
| commit | 0c2639f1d06f9c3cc15f6d988832122d8ed85f8d (patch) | |
| tree | 0d5fe34d17f9da6fc9f2b956b4c55928a7c8a251 | |
| parent | 4eaead515e290dd8968f09245e9f5024fa7bc936 (diff) | |
| download | linux-rt-0c2639f1d06f9c3cc15f6d988832122d8ed85f8d.tar.gz | |
net: provide a way to delegate processing a softirq to ksoftirqd
If the NET_RX uses up all of his budget it moves the following NAPI
invocations into the `ksoftirqd`. On -RT it does not do so. Instead it
rises the NET_RX softirq in its current context again.
In order to get closer to mainline's behaviour this patch provides
__raise_softirq_irqoff_ksoft() which raises the softirq in the ksoftird.
Cc: stable-rt@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| -rw-r--r-- | include/linux/interrupt.h | 8 | ||||
| -rw-r--r-- | kernel/softirq.c | 21 | ||||
| -rw-r--r-- | net/core/dev.c | 2 |
3 files changed, 30 insertions, 1 deletions
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 86628c733be7..ce50b6ebd65d 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -444,6 +444,14 @@ extern void thread_do_softirq(void); extern void open_softirq(int nr, void (*action)(struct softirq_action *)); extern void softirq_init(void); extern void __raise_softirq_irqoff(unsigned int nr); +#ifdef CONFIG_PREEMPT_RT_FULL +extern void __raise_softirq_irqoff_ksoft(unsigned int nr); +#else +static inline void __raise_softirq_irqoff_ksoft(unsigned int nr) +{ + __raise_softirq_irqoff(nr); +} +#endif extern void raise_softirq_irqoff(unsigned int nr); extern void raise_softirq(unsigned int nr); diff --git a/kernel/softirq.c b/kernel/softirq.c index 40dbf5fcc869..a55e80dca611 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -704,6 +704,27 @@ void __raise_softirq_irqoff(unsigned int nr) } /* + * Same as __raise_softirq_irqoff() but will process them in ksoftirqd + */ +void __raise_softirq_irqoff_ksoft(unsigned int nr) +{ + unsigned int mask; + + if (WARN_ON_ONCE(!__this_cpu_read(ksoftirqd) || + !__this_cpu_read(ktimer_softirqd))) + return; + mask = 1UL << nr; + + trace_softirq_raise(nr); + or_softirq_pending(mask); + if (mask & TIMER_SOFTIRQS) + __this_cpu_read(ktimer_softirqd)->softirqs_raised |= mask; + else + __this_cpu_read(ksoftirqd)->softirqs_raised |= mask; + wakeup_proper_softirq(nr); +} + +/* * This function must run with irqs disabled! */ void raise_softirq_irqoff(unsigned int nr) diff --git a/net/core/dev.c b/net/core/dev.c index b89a1dd9f4d8..da674bb38606 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4679,7 +4679,7 @@ out: softnet_break: sd->time_squeeze++; - __raise_softirq_irqoff(NET_RX_SOFTIRQ); + __raise_softirq_irqoff_ksoft(NET_RX_SOFTIRQ); goto out; } |