Adding debian version 4.19.249-2.debian/4.19.249-2debian

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 117 insertions, 0 deletions

diff --git a/debian/patches-rt/0228-cpu-hotplug-Implement-CPU-pinning.patch b/debian/patches-rt/0228-cpu-hotplug-Implement-CPU-pinning.patch
new file mode 100644
index 000000000..9a3b2430f
--- /dev/null
+++ b/debian/patches-rt/0228-cpu-hotplug-Implement-CPU-pinning.patch
@@ -0,0 +1,117 @@
+From 784e4a9806842dc64aa0902210fe4e11984d868a Mon Sep 17 00:00:00 2001
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Wed, 19 Jul 2017 17:31:20 +0200
+Subject: [PATCH 228/347] cpu/hotplug: Implement CPU pinning
+Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz
+
+Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
+---
+ include/linux/sched.h |  1 +
+ kernel/cpu.c          | 38 ++++++++++++++++++++++++++++++++++++++
+ 2 files changed, 39 insertions(+)
+
+diff --git a/include/linux/sched.h b/include/linux/sched.h
+index 577045ae8693..7523c0786a63 100644
+--- a/include/linux/sched.h
++++ b/include/linux/sched.h
+@@ -671,6 +671,7 @@ struct task_struct {
+ #if defined(CONFIG_SMP) && defined(CONFIG_PREEMPT_RT_BASE)
+ 	int				migrate_disable;
+ 	int				migrate_disable_update;
++	int				pinned_on_cpu;
+ # ifdef CONFIG_SCHED_DEBUG
+ 	int				migrate_disable_atomic;
+ # endif
+diff --git a/kernel/cpu.c b/kernel/cpu.c
+index 89a96cc14b39..797216a0b4c6 100644
+--- a/kernel/cpu.c
++++ b/kernel/cpu.c
+@@ -77,6 +77,11 @@ static DEFINE_PER_CPU(struct cpuhp_cpu_state, cpuhp_state) = {
+ 	.fail = CPUHP_INVALID,
+ };
+ 
++#ifdef CONFIG_HOTPLUG_CPU
++static DEFINE_PER_CPU(struct rt_rw_lock, cpuhp_pin_lock) = \
++	__RWLOCK_RT_INITIALIZER(cpuhp_pin_lock);
++#endif
++
+ #if defined(CONFIG_LOCKDEP) && defined(CONFIG_SMP)
+ static struct lockdep_map cpuhp_state_up_map =
+ 	STATIC_LOCKDEP_MAP_INIT("cpuhp_state-up", &cpuhp_state_up_map);
+@@ -288,7 +293,28 @@ static int cpu_hotplug_disabled;
+  */
+ void pin_current_cpu(void)
+ {
++	struct rt_rw_lock *cpuhp_pin;
++	unsigned int cpu;
++	int ret;
++
++again:
++	cpuhp_pin = this_cpu_ptr(&cpuhp_pin_lock);
++	ret = __read_rt_trylock(cpuhp_pin);
++	if (ret) {
++		current->pinned_on_cpu = smp_processor_id();
++		return;
++	}
++	cpu = smp_processor_id();
++	preempt_enable();
++
++	__read_rt_lock(cpuhp_pin);
+ 
++	preempt_disable();
++	if (cpu != smp_processor_id()) {
++		__read_rt_unlock(cpuhp_pin);
++		goto again;
++	}
++	current->pinned_on_cpu = cpu;
+ }
+ 
+ /**
+@@ -296,6 +322,13 @@ void pin_current_cpu(void)
+  */
+ void unpin_current_cpu(void)
+ {
++	struct rt_rw_lock *cpuhp_pin = this_cpu_ptr(&cpuhp_pin_lock);
++
++	if (WARN_ON(current->pinned_on_cpu != smp_processor_id()))
++		cpuhp_pin = per_cpu_ptr(&cpuhp_pin_lock, current->pinned_on_cpu);
++
++	current->pinned_on_cpu = -1;
++	__read_rt_unlock(cpuhp_pin);
+ }
+ 
+ DEFINE_STATIC_PERCPU_RWSEM(cpu_hotplug_lock);
+@@ -920,6 +953,7 @@ static int take_cpu_down(void *_param)
+ 
+ static int takedown_cpu(unsigned int cpu)
+ {
++	struct rt_rw_lock *cpuhp_pin = per_cpu_ptr(&cpuhp_pin_lock, cpu);
+ 	struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
+ 	int err;
+ 
+@@ -932,11 +966,14 @@ static int takedown_cpu(unsigned int cpu)
+ 	 */
+ 	irq_lock_sparse();
+ 
++	__write_rt_lock(cpuhp_pin);
++
+ 	/*
+ 	 * So now all preempt/rcu users must observe !cpu_active().
+ 	 */
+ 	err = stop_machine_cpuslocked(take_cpu_down, NULL, cpumask_of(cpu));
+ 	if (err) {
++		__write_rt_unlock(cpuhp_pin);
+ 		/* CPU refused to die */
+ 		irq_unlock_sparse();
+ 		/* Unpark the hotplug thread so we can rollback there */
+@@ -955,6 +992,7 @@ static int takedown_cpu(unsigned int cpu)
+ 	wait_for_ap_thread(st, false);
+ 	BUG_ON(st->state != CPUHP_AP_IDLE_DEAD);
+ 
++	__write_rt_unlock(cpuhp_pin);
+ 	/* Interrupts are moved away from the dying cpu, reenable alloc/free */
+ 	irq_unlock_sparse();
+ 
+-- 
+2.36.1
+