diff options
Diffstat (limited to 'arch/powerpc/platforms/cell/spufs/sched.c')
| -rw-r--r-- | arch/powerpc/platforms/cell/spufs/sched.c | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c index 67595bc380d..2ad914c4749 100644 --- a/arch/powerpc/platforms/cell/spufs/sched.c +++ b/arch/powerpc/platforms/cell/spufs/sched.c @@ -312,6 +312,15 @@ static struct spu *aff_ref_location(struct spu_context *ctx, int mem_aff, */ node = cpu_to_node(raw_smp_processor_id()); for (n = 0; n < MAX_NUMNODES; n++, node++) { + /* + * "available_spus" counts how many spus are not potentially + * going to be used by other affinity gangs whose reference + * context is already in place. Although this code seeks to + * avoid having affinity gangs with a summed amount of + * contexts bigger than the amount of spus in the node, + * this may happen sporadically. In this case, available_spus + * becomes negative, which is harmless. + */ int available_spus; node = (node < MAX_NUMNODES) ? node : 0; @@ -321,12 +330,10 @@ static struct spu *aff_ref_location(struct spu_context *ctx, int mem_aff, available_spus = 0; mutex_lock(&cbe_spu_info[node].list_mutex); list_for_each_entry(spu, &cbe_spu_info[node].spus, cbe_list) { - if (spu->ctx && spu->ctx->gang - && spu->ctx->aff_offset == 0) - available_spus -= - (spu->ctx->gang->contexts - 1); - else - available_spus++; + if (spu->ctx && spu->ctx->gang && !spu->ctx->aff_offset + && spu->ctx->gang->aff_ref_spu) + available_spus -= spu->ctx->gang->contexts; + available_spus++; } if (available_spus < ctx->gang->contexts) { mutex_unlock(&cbe_spu_info[node].list_mutex); @@ -437,6 +444,11 @@ static void spu_unbind_context(struct spu *spu, struct spu_context *ctx) atomic_dec(&cbe_spu_info[spu->node].reserved_spus); if (ctx->gang) + /* + * If ctx->gang->aff_sched_count is positive, SPU affinity is + * being considered in this gang. Using atomic_dec_if_positive + * allow us to skip an explicit check for affinity in this gang + */ atomic_dec_if_positive(&ctx->gang->aff_sched_count); spu_switch_notify(spu, NULL); |