@@ -239,6 +239,7 @@ static void signal_irq_work(struct irq_work *work)
intel_breadcrumbs_disarm_irq(b);
rcu_read_lock();
+ atomic_inc(&b->signaler_active);
list_for_each_entry_rcu(ce, &b->signalers, signal_link) {
struct i915_request *rq;
@@ -274,6 +275,7 @@ static void signal_irq_work(struct irq_work *work)
}
}
}
+ atomic_dec(&b->signaler_active);
rcu_read_unlock();
llist_for_each_safe(signal, sn, signal) {
@@ -35,6 +35,7 @@ struct intel_breadcrumbs {
spinlock_t signalers_lock; /* protects the list of signalers */
struct list_head signalers;
struct llist_head signaled_requests;
+ atomic_t signaler_active;
spinlock_t irq_lock; /* protects the interrupt from hardirq context */
struct irq_work irq_work; /* for use from inside irq_lock */
@@ -1401,7 +1401,8 @@ static void kick_siblings(struct i915_request *rq, struct intel_context *ce)
* ce->signal_link.
*/
i915_request_cancel_breadcrumb(rq);
- irq_work_sync(&engine->breadcrumbs->irq_work);
+ while (atomic_read(&engine->breadcrumbs->signaler_active))
+ cpu_relax();
}
if (READ_ONCE(ve->request))
Let's only wait for the list iterator when decoupling the virtual breadcrumb, as the signaling of all the requests may take a long time, during which we do not want to keep the tasklet spinning. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> --- drivers/gpu/drm/i915/gt/intel_breadcrumbs.c | 2 ++ drivers/gpu/drm/i915/gt/intel_breadcrumbs_types.h | 1 + drivers/gpu/drm/i915/gt/intel_lrc.c | 3 ++- 3 files changed, 5 insertions(+), 1 deletion(-)