x86/vector: Merge allocate_vector() into assign_vector_locked()

assign_vector_locked() calls allocate_vector() to get a real vector for an
IRQ. If the current target CPU is online and in the new requested affinity
mask, allocate_vector() will return 0 and nothing should be done. But,
assign_vector_locked() calls apic_update_irq_cfg() even in that case which
is pointless.

allocate_vector() is not called from anything else, so the functions can be
merged and in case of no change the apic_update_irq_cfg() can be avoided.

[ tglx: Massaged changelog ]

Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/20180511080956.6316-1-douly.fnst@cn.fujitsu.com
This commit is contained in:
Dou Liyang 2018-05-11 16:09:56 +08:00 committed by Thomas Gleixner
parent 73fcb1a370
commit 2773397171

View File

@ -218,7 +218,8 @@ static int reserve_irq_vector(struct irq_data *irqd)
return 0; return 0;
} }
static int allocate_vector(struct irq_data *irqd, const struct cpumask *dest) static int
assign_vector_locked(struct irq_data *irqd, const struct cpumask *dest)
{ {
struct apic_chip_data *apicd = apic_chip_data(irqd); struct apic_chip_data *apicd = apic_chip_data(irqd);
bool resvd = apicd->has_reserved; bool resvd = apicd->has_reserved;
@ -236,22 +237,12 @@ static int allocate_vector(struct irq_data *irqd, const struct cpumask *dest)
return 0; return 0;
vector = irq_matrix_alloc(vector_matrix, dest, resvd, &cpu); vector = irq_matrix_alloc(vector_matrix, dest, resvd, &cpu);
if (vector > 0)
apic_update_vector(irqd, vector, cpu);
trace_vector_alloc(irqd->irq, vector, resvd, vector); trace_vector_alloc(irqd->irq, vector, resvd, vector);
return vector;
}
static int assign_vector_locked(struct irq_data *irqd,
const struct cpumask *dest)
{
struct apic_chip_data *apicd = apic_chip_data(irqd);
int vector = allocate_vector(irqd, dest);
if (vector < 0) if (vector < 0)
return vector; return vector;
apic_update_vector(irqd, vector, cpu);
apic_update_irq_cfg(irqd, vector, cpu);
apic_update_irq_cfg(irqd, apicd->vector, apicd->cpu);
return 0; return 0;
} }