[Mesa-dev] [PATCH] clover, gallium: add PIPE_COMPUTE_CAP_MAX_THREADS_PER_BLOCK

[Christoph Bumiller]

This is not necessarily the product of MAX_BLOCK_SIZE[i].
---
 src/gallium/docs/source/screen.rst                |    5 +++++
 src/gallium/include/pipe/p_defines.h              |    1 +
 src/gallium/state_trackers/clover/api/device.cpp  |    3 ++-
 src/gallium/state_trackers/clover/core/device.cpp |    7 +++++++
 src/gallium/state_trackers/clover/core/device.hpp |    1 +
 5 files changed, 16 insertions(+), 1 deletions(-)

diff --git a/src/gallium/docs/source/screen.rst b/src/gallium/docs/source/screen.rst
index d912dc6..4e82d34 100644
--- a/src/gallium/docs/source/screen.rst
+++ b/src/gallium/docs/source/screen.rst
@@ -203,6 +203,11 @@ pipe_screen::get_compute_param.
   units.  Value type: ``uint64_t []``.
 * ``PIPE_COMPUTE_CAP_MAX_BLOCK_SIZE``: Maximum block size in thread
   units.  Value type: ``uint64_t []``.
+* ``PIPE_COMPUTE_CAP_MAX_THREADS_PER_BLOCK``: Maximum number of threads that
+  a single block can contain.  Value type: ``uint64_t``.
+  This may be less than the product of the components of MAX_BLOCK_SIZE and is
+  usually limited by the number of threads that can be resident simultaneously
+  on a compute unit.
 * ``PIPE_COMPUTE_CAP_MAX_GLOBAL_SIZE``: Maximum size of the GLOBAL
   resource.  Value type: ``uint64_t``.
 * ``PIPE_COMPUTE_CAP_MAX_LOCAL_SIZE``: Maximum size of the LOCAL
diff --git a/src/gallium/include/pipe/p_defines.h b/src/gallium/include/pipe/p_defines.h
index edcca23..2b6d1be 100644
--- a/src/gallium/include/pipe/p_defines.h
+++ b/src/gallium/include/pipe/p_defines.h
@@ -545,6 +545,7 @@ enum pipe_compute_cap
    PIPE_COMPUTE_CAP_GRID_DIMENSION,
    PIPE_COMPUTE_CAP_MAX_GRID_SIZE,
    PIPE_COMPUTE_CAP_MAX_BLOCK_SIZE,
+   PIPE_COMPUTE_CAP_MAX_THREADS_PER_BLOCK,
    PIPE_COMPUTE_CAP_MAX_GLOBAL_SIZE,
    PIPE_COMPUTE_CAP_MAX_LOCAL_SIZE,
    PIPE_COMPUTE_CAP_MAX_PRIVATE_SIZE,
diff --git a/src/gallium/state_trackers/clover/api/device.cpp b/src/gallium/state_trackers/clover/api/device.cpp
index 0376751..1a9127b 100644
--- a/src/gallium/state_trackers/clover/api/device.cpp
+++ b/src/gallium/state_trackers/clover/api/device.cpp
@@ -87,7 +87,8 @@ clGetDeviceInfo(cl_device_id dev, cl_device_info param,
                                      dev->max_block_size());
 
    case CL_DEVICE_MAX_WORK_GROUP_SIZE:
-      return scalar_property<size_t>(buf, size, size_ret, SIZE_MAX);
+      return scalar_property<size_t>(buf, size, size_ret,
+                                     dev->max_threads_per_block());
 
    case CL_DEVICE_PREFERRED_VECTOR_WIDTH_CHAR:
       return scalar_property<cl_uint>(buf, size, size_ret, 16);
diff --git a/src/gallium/state_trackers/clover/core/device.cpp b/src/gallium/state_trackers/clover/core/device.cpp
index 8390f3f..661f33a 100644
--- a/src/gallium/state_trackers/clover/core/device.cpp
+++ b/src/gallium/state_trackers/clover/core/device.cpp
@@ -143,6 +143,13 @@ _cl_device_id::max_block_size() const {
    return get_compute_param<uint64_t>(pipe, PIPE_COMPUTE_CAP_MAX_BLOCK_SIZE);
 }
 
+size_t
+_cl_device_id::max_threads_per_block() const {
+   return
+      get_compute_param<uint64_t>(pipe,
+                                  PIPE_COMPUTE_CAP_MAX_THREADS_PER_BLOCK)[0];
+}
+
 std::string
 _cl_device_id::device_name() const {
    return pipe->get_name(pipe);
diff --git a/src/gallium/state_trackers/clover/core/device.hpp b/src/gallium/state_trackers/clover/core/device.hpp
index 8f284ba..b69e61f 100644
--- a/src/gallium/state_trackers/clover/core/device.hpp
+++ b/src/gallium/state_trackers/clover/core/device.hpp
@@ -57,6 +57,7 @@ public:
    cl_uint max_const_buffers() const;
 
    std::vector<size_t> max_block_size() const;
+   size_t max_threads_per_block() const;
    std::string device_name() const;
    std::string vendor_name() const;
    std::string ir_target() const;
-- 
1.7.3.4