[Mesa-dev] [PATCHv3 12/16] i965: add drirc option multithread_glsl_compiler

[Chia-I Wu]

Setting it to a non-zero value N will cause shader compilation to be deferred
to a thread pool.  When N is greater than 1, it indicates the maximum number
of threads in the pool.  When N is 1, the number of threads is up to the
driver (two for i965).

Signed-off-by: Chia-I Wu <olv at lunarg.com>
Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>
---
 src/mesa/drivers/dri/common/xmlpool/t_options.h |  4 ++++
 src/mesa/drivers/dri/i965/brw_context.c         | 15 +++++++++++++++
 src/mesa/drivers/dri/i965/intel_screen.c        |  2 ++
 3 files changed, 21 insertions(+)

diff --git a/src/mesa/drivers/dri/common/xmlpool/t_options.h b/src/mesa/drivers/dri/common/xmlpool/t_options.h
index b73a662..7ac0298 100644
--- a/src/mesa/drivers/dri/common/xmlpool/t_options.h
+++ b/src/mesa/drivers/dri/common/xmlpool/t_options.h
@@ -298,6 +298,10 @@ DRI_CONF_OPT_BEGIN_V(texture_heaps,enum,def,"0:2") \
 	DRI_CONF_DESC_END \
 DRI_CONF_OPT_END
 
+#define DRI_CONF_MULTITHREAD_GLSL_COMPILER(def) \
+DRI_CONF_OPT_BEGIN(multithread_glsl_compiler, int, def) \
+        DRI_CONF_DESC(en,gettext("Enable multithreading in the GLSL compiler")) \
+DRI_CONF_OPT_END
 
 
 /**
diff --git a/src/mesa/drivers/dri/i965/brw_context.c b/src/mesa/drivers/dri/i965/brw_context.c
index 216b788..b02128c 100644
--- a/src/mesa/drivers/dri/i965/brw_context.c
+++ b/src/mesa/drivers/dri/i965/brw_context.c
@@ -624,6 +624,17 @@ brw_process_driconf_options(struct brw_context *brw)
 
    ctx->Const.AllowGLSLExtensionDirectiveMidShader =
       driQueryOptionb(options, "allow_glsl_extension_directive_midshader");
+
+   const int multithread_glsl_compiler =
+      driQueryOptioni(options, "multithread_glsl_compiler");
+   if (multithread_glsl_compiler > 0) {
+      const int max_threads = (multithread_glsl_compiler > 1) ?
+         multithread_glsl_compiler : 2;
+
+      _mesa_enable_glsl_threadpool(ctx, max_threads);
+      ctx->Const.DeferCompileShader = GL_TRUE;
+      ctx->Const.DeferLinkProgram = GL_TRUE;
+   }
 }
 
 GLboolean
@@ -828,6 +839,10 @@ brwCreateContext(gl_api api,
    if (INTEL_DEBUG & DEBUG_SHADER_TIME)
       brw_init_shader_time(brw);
 
+   /* brw_shader_precompile is not thread-safe */
+   if (brw->precompile)
+      ctx->Const.DeferLinkProgram = GL_FALSE;
+
    _mesa_compute_version(ctx);
 
    _mesa_initialize_dispatch_tables(ctx);
diff --git a/src/mesa/drivers/dri/i965/intel_screen.c b/src/mesa/drivers/dri/i965/intel_screen.c
index 9e743ee..95850c1 100644
--- a/src/mesa/drivers/dri/i965/intel_screen.c
+++ b/src/mesa/drivers/dri/i965/intel_screen.c
@@ -48,6 +48,8 @@ static const __DRIconfigOptionsExtension brw_config_options = {
 DRI_CONF_BEGIN
    DRI_CONF_SECTION_PERFORMANCE
       DRI_CONF_VBLANK_MODE(DRI_CONF_VBLANK_ALWAYS_SYNC)
+      DRI_CONF_MULTITHREAD_GLSL_COMPILER(0)
+
       /* Options correspond to DRI_CONF_BO_REUSE_DISABLED,
        * DRI_CONF_BO_REUSE_ALL
        */
-- 
2.0.0.rc2