diff options
Diffstat (limited to 'debian/patches-rt/0230-hotplug-duct-tape-RT-rwlock-usage-for-non-RT.patch')
| -rw-r--r-- | debian/patches-rt/0230-hotplug-duct-tape-RT-rwlock-usage-for-non-RT.patch | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/debian/patches-rt/0230-hotplug-duct-tape-RT-rwlock-usage-for-non-RT.patch b/debian/patches-rt/0230-hotplug-duct-tape-RT-rwlock-usage-for-non-RT.patch new file mode 100644 index 000000000..f60b81343 --- /dev/null +++ b/debian/patches-rt/0230-hotplug-duct-tape-RT-rwlock-usage-for-non-RT.patch @@ -0,0 +1,102 @@ +From 3ed5cb0e7f86a61b58b20f64a79148a2a80dac29 Mon Sep 17 00:00:00 2001 +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Fri, 4 Aug 2017 18:31:00 +0200 +Subject: [PATCH 230/347] hotplug: duct-tape RT-rwlock usage for non-RT +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz + +This type is only available on -RT. We need to craft something for +non-RT. Since the only migrate_disable() user is -RT only, there is no +damage. + +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + kernel/cpu.c | 14 +++++++++++++- + 1 file changed, 13 insertions(+), 1 deletion(-) + +diff --git a/kernel/cpu.c b/kernel/cpu.c +index 797216a0b4c6..f6511c62c9a4 100644 +--- a/kernel/cpu.c ++++ b/kernel/cpu.c +@@ -77,7 +77,7 @@ static DEFINE_PER_CPU(struct cpuhp_cpu_state, cpuhp_state) = { + .fail = CPUHP_INVALID, + }; + +-#ifdef CONFIG_HOTPLUG_CPU ++#if defined(CONFIG_HOTPLUG_CPU) && defined(CONFIG_PREEMPT_RT_FULL) + static DEFINE_PER_CPU(struct rt_rw_lock, cpuhp_pin_lock) = \ + __RWLOCK_RT_INITIALIZER(cpuhp_pin_lock); + #endif +@@ -293,6 +293,7 @@ static int cpu_hotplug_disabled; + */ + void pin_current_cpu(void) + { ++#ifdef CONFIG_PREEMPT_RT_FULL + struct rt_rw_lock *cpuhp_pin; + unsigned int cpu; + int ret; +@@ -315,6 +316,7 @@ void pin_current_cpu(void) + goto again; + } + current->pinned_on_cpu = cpu; ++#endif + } + + /** +@@ -322,6 +324,7 @@ void pin_current_cpu(void) + */ + void unpin_current_cpu(void) + { ++#ifdef CONFIG_PREEMPT_RT_FULL + struct rt_rw_lock *cpuhp_pin = this_cpu_ptr(&cpuhp_pin_lock); + + if (WARN_ON(current->pinned_on_cpu != smp_processor_id())) +@@ -329,6 +332,7 @@ void unpin_current_cpu(void) + + current->pinned_on_cpu = -1; + __read_rt_unlock(cpuhp_pin); ++#endif + } + + DEFINE_STATIC_PERCPU_RWSEM(cpu_hotplug_lock); +@@ -953,7 +957,9 @@ static int take_cpu_down(void *_param) + + static int takedown_cpu(unsigned int cpu) + { ++#ifdef CONFIG_PREEMPT_RT_FULL + struct rt_rw_lock *cpuhp_pin = per_cpu_ptr(&cpuhp_pin_lock, cpu); ++#endif + struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); + int err; + +@@ -966,14 +972,18 @@ static int takedown_cpu(unsigned int cpu) + */ + irq_lock_sparse(); + ++#ifdef CONFIG_PREEMPT_RT_FULL + __write_rt_lock(cpuhp_pin); ++#endif + + /* + * So now all preempt/rcu users must observe !cpu_active(). + */ + err = stop_machine_cpuslocked(take_cpu_down, NULL, cpumask_of(cpu)); + if (err) { ++#ifdef CONFIG_PREEMPT_RT_FULL + __write_rt_unlock(cpuhp_pin); ++#endif + /* CPU refused to die */ + irq_unlock_sparse(); + /* Unpark the hotplug thread so we can rollback there */ +@@ -992,7 +1002,9 @@ static int takedown_cpu(unsigned int cpu) + wait_for_ap_thread(st, false); + BUG_ON(st->state != CPUHP_AP_IDLE_DEAD); + ++#ifdef CONFIG_PREEMPT_RT_FULL + __write_rt_unlock(cpuhp_pin); ++#endif + /* Interrupts are moved away from the dying cpu, reenable alloc/free */ + irq_unlock_sparse(); + +-- +2.36.1 + |