radeonsi: drop unfinished shader compilations when destroying shaders

If we enqueue too many jobs and destroy the GL context, it may take
several seconds before the jobs finish. Just drop them instead.

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

src/gallium/drivers/radeonsi/si_compute.c

@@ -860,7 +860,8 @@ static void si_delete_compute_state(struct pipe_context *ctx, void* state){
 	}
 
 	if (program->ir_type == PIPE_SHADER_IR_TGSI) {
-		util_queue_fence_wait(&program->ready);
+		util_queue_drop_job(&sctx->screen->shader_compiler_queue,
+				    &program->ready);
 		util_queue_fence_destroy(&program->ready);
 	}
 

src/gallium/drivers/radeonsi/si_state_shaders.c

@@ -2258,7 +2258,8 @@ static void si_bind_ps_shader(struct pipe_context *ctx, void *state)
 static void si_delete_shader(struct si_context *sctx, struct si_shader *shader)
 {
 	if (shader->is_optimized) {
-		util_queue_fence_wait(&shader->optimized_ready);
+		util_queue_drop_job(&sctx->screen->shader_compiler_queue,
+				    &shader->optimized_ready);
 		util_queue_fence_destroy(&shader->optimized_ready);
 	}
 
@@ -2315,7 +2316,7 @@ static void si_destroy_shader_selector(struct si_context *sctx,
 		[PIPE_SHADER_FRAGMENT] = &sctx->ps_shader,
 	};
 
-	util_queue_fence_wait(&sel->ready);
+	util_queue_drop_job(&sctx->screen->shader_compiler_queue, &sel->ready);
 
 	if (current_shader[sel->type]->cso == sel) {
 		current_shader[sel->type]->cso = NULL;