[tip:x86/urgent] x86/irq: Remove the cpumask allocation from send_cleanup_vector()

From: tip-bot for Thomas Gleixner
Date: Sat Jan 16 2016 - 16:20:49 EST


Commit-ID: 5da0c1217f05d2ccc9a8ed6e6e5c23a8a1d24dd6
Gitweb: http://git.kernel.org/tip/5da0c1217f05d2ccc9a8ed6e6e5c23a8a1d24dd6
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Thu, 31 Dec 2015 16:30:52 +0000
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Fri, 15 Jan 2016 13:44:01 +0100

x86/irq: Remove the cpumask allocation from send_cleanup_vector()

There is no need to allocate a new cpumask for sending the cleanup vector. The
old_domain mask is now protected by the vector_lock, so we can safely remove
the offline cpus from it and send the IPI with the resulting mask.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Tested-by: Borislav Petkov <bp@xxxxxxxxx>
Tested-by: Joe Lawrence <joe.lawrence@xxxxxxxxxxx>
Cc: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
Cc: Jeremiah Mahler <jmmahler@xxxxxxxxx>
Cc: andy.shevchenko@xxxxxxxxx
Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx #4.3+
Link: http://lkml.kernel.org/r/20151231160106.967993932@xxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
arch/x86/kernel/apic/vector.c | 16 +++-------------
1 file changed, 3 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index ed62f9c..91dc274 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -530,21 +530,11 @@ static struct irq_chip lapic_controller = {
#ifdef CONFIG_SMP
static void __send_cleanup_vector(struct apic_chip_data *data)
{
- cpumask_var_t cleanup_mask;
-
raw_spin_lock(&vector_lock);
+ cpumask_and(data->old_domain, data->old_domain, cpu_online_mask);
data->move_in_progress = 0;
- if (unlikely(!alloc_cpumask_var(&cleanup_mask, GFP_ATOMIC))) {
- unsigned int i;
-
- for_each_cpu_and(i, data->old_domain, cpu_online_mask)
- apic->send_IPI_mask(cpumask_of(i),
- IRQ_MOVE_CLEANUP_VECTOR);
- } else {
- cpumask_and(cleanup_mask, data->old_domain, cpu_online_mask);
- apic->send_IPI_mask(cleanup_mask, IRQ_MOVE_CLEANUP_VECTOR);
- free_cpumask_var(cleanup_mask);
- }
+ if (!cpumask_empty(data->old_domain))
+ apic->send_IPI_mask(data->old_domain, IRQ_MOVE_CLEANUP_VECTOR);
raw_spin_unlock(&vector_lock);
}