Some powerpc platforms use this to move IRQs away from a CPU
being unplugged. This function has several bugs such as not
taking the right locks or failing to NULL check pointers.
There's a new generic function doing exactly the same thing
without all the bugs, so let's use it instead.
Signed-off-by: Benjamin Herrenschmidt <b...@kernel.crashing.org>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/smp.h | 1 -
arch/powerpc/kernel/irq.c | 40 ----------------------------------------
arch/powerpc/kernel/smp.c | 9 ++++++++-
4 files changed, 9 insertions(+), 42 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 97a8bc8..29fb0e6 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -431,6 +431,7 @@ config HOTPLUG_CPU
bool "Support for enabling/disabling CPUs"
depends on SMP && (PPC_PSERIES || \
PPC_PMAC || PPC_POWERNV || FSL_SOC_BOOKE)
+ select GENERIC_IRQ_MIGRATION
---help---
Say Y here to be able to disable and re-enable individual
CPUs at runtime on SMP machines.
diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h
index 2f8e36f..63fa780 100644
--- a/arch/powerpc/include/asm/smp.h
+++ b/arch/powerpc/include/asm/smp.h
@@ -62,7 +62,6 @@ extern void smp_generic_take_timebase(void);
DECLARE_PER_CPU(unsigned int, cpu_pvr);
#ifdef CONFIG_HOTPLUG_CPU
-extern void migrate_irqs(void);
int generic_cpu_disable(void);
void generic_cpu_die(unsigned int cpu);
void generic_set_cpu_dead(unsigned int cpu);
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index a018f5c..8ee7b44 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -442,46 +442,6 @@ u64 arch_irq_stat_cpu(unsigned int cpu)
return sum;
}
-#ifdef CONFIG_HOTPLUG_CPU
-void migrate_irqs(void)
-{
- struct irq_desc *desc;
- unsigned int irq;
- static int warned;
- cpumask_var_t mask;
- const struct cpumask *map = cpu_online_mask;
-
- alloc_cpumask_var(&mask, GFP_KERNEL);
-
- for_each_irq_desc(irq, desc) {
- struct irq_data *data;
- struct irq_chip *chip;
-
- data = irq_desc_get_irq_data(desc);
- if (irqd_is_per_cpu(data))
- continue;
-
- chip = irq_data_get_irq_chip(data);
-
- cpumask_and(mask, irq_data_get_affinity_mask(data), map);
- if (cpumask_any(mask) >= nr_cpu_ids) {
- pr_warn("Breaking affinity for irq %i\n", irq);
- cpumask_copy(mask, map);
- }
- if (chip->irq_set_affinity)
- chip->irq_set_affinity(data, mask, true);
- else if (desc->action && !(warned++))
- pr_err("Cannot set affinity for irq %i\n", irq);
- }
-
- free_cpumask_var(mask);
-
- local_irq_enable();
- mdelay(1);
- local_irq_disable();
-}
-#endif
-
static inline void check_stack_overflow(void)
{
#ifdef CONFIG_DEBUG_STACKOVERFLOW
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index b12f5f0..6e61cdb 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -439,7 +439,14 @@ int generic_cpu_disable(void)
#ifdef CONFIG_PPC64
vdso_data->processorCount--;
#endif
- migrate_irqs();
+ /* Update affinity of all IRQs previously aimed at this CPU */
+ irq_migrate_all_off_this_cpu();
+
+ /* Give the CPU time to drain in-flight ones */
+ local_irq_enable();
+ mdelay(1);
+ local_irq_disable();
+
return 0;
}
--
2.9.3
