diff options
Diffstat (limited to 'debian/patches-rt/0228-cpu-hotplug-Implement-CPU-pinning.patch')
| -rw-r--r-- | debian/patches-rt/0228-cpu-hotplug-Implement-CPU-pinning.patch | 117 |
1 files changed, 0 insertions, 117 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 deleted file mode 100644 index 9a3b2430f..000000000 --- a/debian/patches-rt/0228-cpu-hotplug-Implement-CPU-pinning.patch +++ /dev/null @@ -1,117 +0,0 @@ -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 - |