drm/i915: Mark up protected uses of 'i915_request_completed'

When we know that we are inside the timeline mutex, or inside the
submission flow (under active.lock or the holder's rcu lock), we know
that the rq->hwsp is stable and we can use the simpler direct version.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210114135612.13210-1-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index 68f5876..cac0c52 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -408,7 +408,7 @@ __active_engine(struct i915_request *rq, struct intel_engine_cs **active)
        }
 
        if (i915_request_is_active(rq)) {
-               if (!i915_request_completed(rq))
+               if (!__i915_request_is_complete(rq))
                        *active = locked;
                ret = true;
        }

diff --git a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c
index be2c285..d098fc0 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c
+++ b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c
@@ -517,8 +517,8 @@ static void print_signals(struct intel_breadcrumbs *b, struct drm_printer *p)
                list_for_each_entry_rcu(rq, &ce->signals, signal_link)
                        drm_printf(p, "\t[%llx:%llx%s] @ %dms\n",
                                   rq->fence.context, rq->fence.seqno,
-                                  i915_request_completed(rq) ? "!" :
-                                  i915_request_started(rq) ? "*" :
+                                  __i915_request_is_complete(rq) ? "!" :
+                                  __i915_request_has_started(rq) ? "*" :
                                   "",
                                   jiffies_to_msecs(jiffies - rq->emitted_jiffies));
        }

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index fa76602..3fe44cd 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -1811,7 +1811,7 @@ intel_engine_find_active_request(struct intel_engine_cs *engine)
                struct intel_timeline *tl = request->context->timeline;
 
                list_for_each_entry_from_reverse(request, &tl->requests, link) {
-                       if (i915_request_completed(request))
+                       if (__i915_request_is_complete(request))
                                break;
 
                        active = request;
@@ -1822,10 +1822,10 @@ intel_engine_find_active_request(struct intel_engine_cs *engine)
                return active;
 
        list_for_each_entry(request, &engine->active.requests, sched.link) {
-               if (i915_request_completed(request))
+               if (__i915_request_is_complete(request))
                        continue;
 
-               if (!i915_request_started(request))
+               if (!__i915_request_has_started(request))
                        continue;
 
                /* More than one preemptible request may match! */

diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
index 33c7495..269492b 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
@@ -3291,7 +3291,7 @@ static void rcu_virtual_context_destroy(struct work_struct *wrk)
 
                old = fetch_and_zero(&ve->request);
                if (old) {
-                       GEM_BUG_ON(!i915_request_completed(old));
+                       GEM_BUG_ON(!__i915_request_is_complete(old));
                        __i915_request_submit(old);
                        i915_request_put(old);
                }
@@ -3568,7 +3568,7 @@ static void virtual_submit_request(struct i915_request *rq)
        }
 
        if (ve->request) { /* background completion from preempt-to-busy */
-               GEM_BUG_ON(!i915_request_completed(ve->request));
+               GEM_BUG_ON(!__i915_request_is_complete(ve->request));
                __i915_request_submit(ve->request);
                i915_request_put(ve->request);
        }

diff --git a/drivers/gpu/drm/i915/gt/intel_reset.c b/drivers/gpu/drm/i915/gt/intel_reset.c
index 0a1f93f..61410cd 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_reset.c
+++ b/drivers/gpu/drm/i915/gt/intel_reset.c
@@ -151,8 +151,7 @@ static void mark_innocent(struct i915_request *rq)
 void __i915_request_reset(struct i915_request *rq, bool guilty)
 {
        RQ_TRACE(rq, "guilty? %s\n", yesno(guilty));
-
-       GEM_BUG_ON(i915_request_completed(rq));
+       GEM_BUG_ON(__i915_request_is_complete(rq));
 
        rcu_read_lock(); /* protect the GEM context */
        if (guilty) {

diff --git a/drivers/gpu/drm/i915/gt/intel_ring_submission.c b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
index 597eaea..8d0964d 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
@@ -389,12 +389,14 @@ static void reset_rewind(struct intel_engine_cs *engine, bool stalled)
 
        rq = NULL;
        spin_lock_irqsave(&engine->active.lock, flags);
+       rcu_read_lock();
        list_for_each_entry(pos, &engine->active.requests, sched.link) {
-               if (!i915_request_completed(pos)) {
+               if (!__i915_request_is_complete(pos)) {
                        rq = pos;
                        break;
                }
        }
+       rcu_read_unlock();
 
        /*
         * The guilty request will get skipped on a hung engine.

diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.c b/drivers/gpu/drm/i915/gt/intel_timeline.c
index 7fe0591..037b0e3 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_timeline.c
+++ b/drivers/gpu/drm/i915/gt/intel_timeline.c
@@ -582,11 +582,11 @@ int intel_timeline_read_hwsp(struct i915_request *from,
 
        rcu_read_lock();
        cl = rcu_dereference(from->hwsp_cacheline);
-       if (i915_request_completed(from)) /* confirm cacheline is valid */
+       if (i915_request_signaled(from)) /* confirm cacheline is valid */
                goto unlock;
        if (unlikely(!i915_active_acquire_if_busy(&cl->active)))
                goto unlock; /* seqno wrapped and completed! */
-       if (unlikely(i915_request_completed(from)))
+       if (unlikely(__i915_request_is_complete(from)))
                goto release;
        rcu_read_unlock();
 

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 0b1a46a..784c05a 100644 (file)
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -276,7 +276,7 @@ static void remove_from_engine(struct i915_request *rq)
 
 bool i915_request_retire(struct i915_request *rq)
 {
-       if (!i915_request_completed(rq))
+       if (!__i915_request_is_complete(rq))
                return false;
 
        RQ_TRACE(rq, "\n");
@@ -342,8 +342,7 @@ void i915_request_retire_upto(struct i915_request *rq)
        struct i915_request *tmp;
 
        RQ_TRACE(rq, "\n");
-
-       GEM_BUG_ON(!i915_request_completed(rq));
+       GEM_BUG_ON(!__i915_request_is_complete(rq));
 
        do {
                tmp = list_first_entry(&tl->requests, typeof(*tmp), link);
@@ -552,7 +551,7 @@ bool __i915_request_submit(struct i915_request *request)
         * dropped upon retiring. (Otherwise if resubmit a *retired*
         * request, this would be a horrible use-after-free.)
         */
-       if (i915_request_completed(request))
+       if (__i915_request_is_complete(request))
                goto xfer;
 
        if (unlikely(intel_context_is_banned(request->context)))
@@ -652,7 +651,7 @@ void __i915_request_unsubmit(struct i915_request *request)
                i915_request_cancel_breadcrumb(request);
 
        /* We've already spun, don't charge on resubmitting. */
-       if (request->sched.semaphores && i915_request_started(request))
+       if (request->sched.semaphores && __i915_request_has_started(request))
                request->sched.semaphores = 0;
 
        /*
@@ -864,7 +863,7 @@ __i915_request_create(struct intel_context *ce, gfp_t gfp)
        RCU_INIT_POINTER(rq->timeline, tl);
        RCU_INIT_POINTER(rq->hwsp_cacheline, tl->hwsp_cacheline);
        rq->hwsp_seqno = tl->hwsp_seqno;
-       GEM_BUG_ON(i915_request_completed(rq));
+       GEM_BUG_ON(__i915_request_is_complete(rq));
 
        rq->rcustate = get_state_synchronize_rcu(); /* acts as smp_mb() */
 
@@ -978,7 +977,7 @@ i915_request_await_start(struct i915_request *rq, struct i915_request *signal)
                struct i915_request *prev;
 
                /* Confirm signal has not been retired, the link is valid */
-               if (unlikely(i915_request_started(signal)))
+               if (unlikely(__i915_request_has_started(signal)))
                        break;
 
                /* Is signal the earliest request on its timeline? */
@@ -1520,7 +1519,7 @@ __i915_request_add_to_timeline(struct i915_request *rq)
         */
        prev = to_request(__i915_active_fence_set(&timeline->last_request,
                                                  &rq->fence));
-       if (prev && !i915_request_completed(prev)) {
+       if (prev && !__i915_request_is_complete(prev)) {
                /*
                 * The requests are supposed to be kept in order. However,
                 * we need to be wary in case the timeline->last_request
@@ -1897,10 +1896,10 @@ static char queue_status(const struct i915_request *rq)
 
 static const char *run_status(const struct i915_request *rq)
 {
-       if (i915_request_completed(rq))
+       if (__i915_request_is_complete(rq))
                return "!";
 
-       if (i915_request_started(rq))
+       if (__i915_request_has_started(rq))
                return "*";
 
        if (!i915_sw_fence_signaled(&rq->semaphore))

diff --git a/drivers/gpu/drm/i915/i915_scheduler.c b/drivers/gpu/drm/i915/i915_scheduler.c
index 318e359..7144239 100644 (file)
--- a/drivers/gpu/drm/i915/i915_scheduler.c
+++ b/drivers/gpu/drm/i915/i915_scheduler.c
@@ -520,7 +520,7 @@ void i915_request_show_with_schedule(struct drm_printer *m,
                if (signaler->timeline == rq->timeline)
                        continue;
 
-               if (i915_request_completed(signaler))
+               if (__i915_request_is_complete(signaler))
                        continue;
 
                i915_request_show(m, signaler, prefix, indent + 2);