Does it always crash with llama-bench?

Waiting for each event already makes sure the corresponding kernel is complete. I think it's more likely events are being released twice. This happened with llama-mtmd. I will also take a closer look into this crash.

Does it always crash with llama-bench?

Waiting for each event already makes sure the corresponding kernel is complete. I think it's more likely events are being released twice. This happened with llama-mtmd. I will also take a closer look into this crash.

Yes, it was crashing consistently. I believe the crash occurs at clWaitForEvents, not clReleaseEvent. The issue only happens during teardown, so it might be a driver issue

llama-bench creates a new context for each new params combination instance. profiling_info needs to be cleared in free() so that it will start with clean slate and previously freed events will not be waited on again. We don't need to remove clWaitForEvents and clReleaseEvent or add clFinish.

The following should fix llama-bench crash,

diff --git a/ggml/src/ggml-opencl/ggml-opencl.cpp b/ggml/src/ggml-opencl/ggml-opencl.cpp
index c9316eb7..ceb797a9 100644
--- a/ggml/src/ggml-opencl/ggml-opencl.cpp
+++ b/ggml/src/ggml-opencl/ggml-opencl.cpp
@@ -600,6 +600,7 @@ struct ggml_backend_opencl_context {
         if (ref_count == 0) {
 #ifdef GGML_OPENCL_PROFILING
             write_profiling_info();
+            profiling_info.clear();
 #endif
         }
     }

The following should fix llama-bench crash,

diff --git a/ggml/src/ggml-opencl/ggml-opencl.cpp b/ggml/src/ggml-opencl/ggml-opencl.cpp
index c9316eb7..ceb797a9 100644
--- a/ggml/src/ggml-opencl/ggml-opencl.cpp
+++ b/ggml/src/ggml-opencl/ggml-opencl.cpp
@@ -600,6 +600,7 @@ struct ggml_backend_opencl_context {
         if (ref_count == 0) {
 #ifdef GGML_OPENCL_PROFILING
             write_profiling_info();
+            profiling_info.clear();
 #endif
         }
     }

Alright, I just tested it and it works. Closing this PR and opening a new one since I was trying to merge into the wrong branch