[PATCH] idr: Use this_cpu_ptr() for percpu_ida

From: Kent Overstreet
Date: Wed Aug 07 2013 - 15:52:58 EST



diff --git a/lib/idr.c b/lib/idr.c
index fb374c3..320ffea 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -748,12 +748,10 @@ int percpu_ida_alloc(struct percpu_ida *pool, gfp_t gfp)
DEFINE_WAIT(wait);
struct percpu_ida_cpu *tags;
unsigned long flags;
- unsigned this_cpu;
int tag;

local_irq_save(flags);
- this_cpu = smp_processor_id();
- tags = per_cpu_ptr(pool->tag_cpu, this_cpu);
+ tags = this_cpu_ptr(pool->tag_cpu);

/* Fastpath */
tag = alloc_local_tag(pool, tags);
@@ -782,7 +780,8 @@ int percpu_ida_alloc(struct percpu_ida *pool, gfp_t gfp)
if (tags->nr_free) {
tag = tags->freelist[--tags->nr_free];
if (tags->nr_free)
- set_bit(this_cpu, pool->cpus_have_tags);
+ set_bit(smp_processor_id(),
+ pool->cpus_have_tags);
}

spin_unlock(&pool->ida.lock);
@@ -794,8 +793,7 @@ int percpu_ida_alloc(struct percpu_ida *pool, gfp_t gfp)
schedule();

local_irq_save(flags);
- this_cpu = smp_processor_id();
- tags = per_cpu_ptr(pool->tag_cpu, this_cpu);
+ tags = this_cpu_ptr(pool->tag_cpu);
}

finish_wait(&pool->wait, &wait);
@@ -814,13 +812,12 @@ void percpu_ida_free(struct percpu_ida *pool, unsigned tag)
{
struct percpu_ida_cpu *tags;
unsigned long flags;
- unsigned nr_free, this_cpu;
+ unsigned nr_free;

BUG_ON(tag >= pool->nr_tags);

local_irq_save(flags);
- this_cpu = smp_processor_id();
- tags = per_cpu_ptr(pool->tag_cpu, this_cpu);
+ tags = this_cpu_ptr(pool->tag_cpu);

spin_lock(&tags->lock);
tags->freelist[tags->nr_free++] = tag;
@@ -829,7 +826,8 @@ void percpu_ida_free(struct percpu_ida *pool, unsigned tag)
spin_unlock(&tags->lock);

if (nr_free == 1) {
- set_bit(this_cpu, pool->cpus_have_tags);
+ set_bit(smp_processor_id(),
+ pool->cpus_have_tags);
wake_up(&pool->wait);
}

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/