sched, block: Unify cache detection

The block layer has some code trying to determine if two CPUs share a
cache, the scheduler has a similar function. Expose the function used
by the scheduler and make the block layer use it, thereby removing the
block layers usage of CONFIG_SCHED* and topology bits.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jens Axboe <axboe@kernel.dk>
Link: http://lkml.kernel.org/r/1327579450.2446.95.camel@twins

1 files changed, 3 insertions, 3 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 5255c9d2e05..d7c43227311 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1507,7 +1507,7 @@ static int ttwu_activate_remote(struct task_struct *p, int wake_flags)
 }
 #endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */
 
-static inline int ttwu_share_cache(int this_cpu, int that_cpu)
+bool cpus_share_cache(int this_cpu, int that_cpu)
 {
         return per_cpu(sd_llc_id, this_cpu) == per_cpu(sd_llc_id, that_cpu);
 }
@@ -1518,7 +1518,7 @@ static void ttwu_queue(struct task_struct *p, int cpu)
         struct rq *rq = cpu_rq(cpu);
 
 #if defined(CONFIG_SMP)
-        if (sched_feat(TTWU_QUEUE) && !ttwu_share_cache(smp_processor_id(), cpu)) {
+        if (sched_feat(TTWU_QUEUE) && !cpus_share_cache(smp_processor_id(), cpu)) {
                 sched_clock_cpu(cpu); /* sync clocks x-cpu */
                 ttwu_queue_remote(p, cpu);
                 return;
@@ -5754,7 +5754,7 @@ static void destroy_sched_domains(struct sched_domain *sd, int cpu)
  *
  * Also keep a unique ID per domain (we use the first cpu number in
  * the cpumask of the domain), this allows us to quickly tell if
- * two cpus are in the same cache domain, see ttwu_share_cache().
+ * two cpus are in the same cache domain, see cpus_share_cache().
  */
 DEFINE_PER_CPU(struct sched_domain *, sd_llc);
 DEFINE_PER_CPU(int, sd_llc_id);