From b52b89da097896ac265d1f875aeb0bfd92a9dd38 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Wed, 25 Sep 2013 11:43:28 +0100 Subject: [PATCH] drm/i915: Add a tracepoint for using a semaphore MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit So that we can find the callers who introduce a ring stall. A single ring stall is not too unwelcome, the right issue becomes when they start to interlock and prevent any concurrent work. That, however, is a little tricker to detect with a mere tracepoint! v2: Rebrand it as a ring event, rather than an object event. v3: Include the seqno in the tracepoint for posterity or something. Signed-off-by: Chris Wilson Reviewed-by: Ville Syrjälä Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_gem.c | 1 + drivers/gpu/drm/i915/i915_trace.h | 26 ++++++++++++++++++++++++++ 2 files changed, 27 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 1a0b74d..3ae925b 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2625,6 +2625,7 @@ i915_gem_object_sync(struct drm_i915_gem_object *obj, if (ret) return ret; + trace_i915_gem_ring_sync_to(from, to, seqno); ret = to->sync_to(to, from, seqno); if (!ret) /* We use last_read_seqno because sync_to() diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h index daa6fdf..6e580c9 100644 --- a/drivers/gpu/drm/i915/i915_trace.h +++ b/drivers/gpu/drm/i915/i915_trace.h @@ -248,6 +248,32 @@ TRACE_EVENT(i915_gem_evict_vm, TP_printk("dev=%d, vm=%p", __entry->vm->dev->primary->index, __entry->vm) ); +TRACE_EVENT(i915_gem_ring_sync_to, + TP_PROTO(struct intel_ring_buffer *from, + struct intel_ring_buffer *to, + u32 seqno), + TP_ARGS(from, to, seqno), + + TP_STRUCT__entry( + __field(u32, dev) + __field(u32, sync_from) + __field(u32, sync_to) + __field(u32, seqno) + ), + + TP_fast_assign( + __entry->dev = from->dev->primary->index; + __entry->sync_from = from->id; + __entry->sync_to = to->id; + __entry->seqno = seqno; + ), + + TP_printk("dev=%u, sync-from=%u, sync-to=%u, seqno=%u", + __entry->dev, + __entry->sync_from, __entry->sync_to, + __entry->seqno) +); + TRACE_EVENT(i915_gem_ring_dispatch, TP_PROTO(struct intel_ring_buffer *ring, u32 seqno, u32 flags), TP_ARGS(ring, seqno, flags), -- 2.7.4