powerpc/spufs: synchronize interaction between spu exception handling and time slicing

Time slicing can occur at the same time as spu exception handling
resulting in the wakeup of the wrong thread.

This change uses the the spu's register_lock to enforce synchronization
between bind/unbind and spu exception handling so that they are
mutually exclusive.

Signed-off-by: Luke Browning <lukebrowning@us.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
This commit is contained in:
Luke Browning
2008-06-13 14:17:35 +10:00
committed by Jeremy Kerr
parent 1f64643aa5
commit 2c911a14b7
2 changed files with 37 additions and 19 deletions

View File

@@ -230,19 +230,23 @@ static void spu_bind_context(struct spu *spu, struct spu_context *ctx)
ctx->stats.slb_flt_base = spu->stats.slb_flt;
ctx->stats.class2_intr_base = spu->stats.class2_intr;
spu_associate_mm(spu, ctx->owner);
spin_lock_irq(&spu->register_lock);
spu->ctx = ctx;
spu->flags = 0;
ctx->spu = spu;
ctx->ops = &spu_hw_ops;
spu->pid = current->pid;
spu->tgid = current->tgid;
spu_associate_mm(spu, ctx->owner);
spu->ibox_callback = spufs_ibox_callback;
spu->wbox_callback = spufs_wbox_callback;
spu->stop_callback = spufs_stop_callback;
spu->mfc_callback = spufs_mfc_callback;
mb();
spin_unlock_irq(&spu->register_lock);
spu_unmap_mappings(ctx);
spu_switch_log_notify(spu, ctx, SWITCH_LOG_START, 0);
spu_restore(&ctx->csa, spu);
spu->timestamp = jiffies;
@@ -423,18 +427,22 @@ static void spu_unbind_context(struct spu *spu, struct spu_context *ctx)
spu_unmap_mappings(ctx);
spu_save(&ctx->csa, spu);
spu_switch_log_notify(spu, ctx, SWITCH_LOG_STOP, 0);
spin_lock_irq(&spu->register_lock);
spu->timestamp = jiffies;
ctx->state = SPU_STATE_SAVED;
spu->ibox_callback = NULL;
spu->wbox_callback = NULL;
spu->stop_callback = NULL;
spu->mfc_callback = NULL;
spu_associate_mm(spu, NULL);
spu->pid = 0;
spu->tgid = 0;
ctx->ops = &spu_backing_ops;
spu->flags = 0;
spu->ctx = NULL;
spin_unlock_irq(&spu->register_lock);
spu_associate_mm(spu, NULL);
ctx->stats.slb_flt +=
(spu->stats.slb_flt - ctx->stats.slb_flt_base);