[Mesa-dev] [PATCH] radv: using tls to store llvm related info and speed up compiles (v6)

Dave Airlie airlied at gmail.com
Tue Jul 3 01:26:44 UTC 2018


From: Dave Airlie <airlied at redhat.com>

I'd like to encourage people to test this to see if it helps (like
does it make app startup better or less hitching in dxvk).

The basic idea is to store a bunch of LLVM related data structs
in thread local storage so we can avoid reiniting them every time
we compile a shader. Since we know llvm objects aren't thread safe
it has to be stored using TLS to avoid any collisions.

This should remove all the fixed overheads setup costs of creating
the pass manager each time.

This takes a demo app time to compile the radv meta shaders on nocache
and exit from 1.7s to 1s. It also has been reported to take the startup
time of uncached shaders on RoTR from 12m24s to 11m35s (Alex)

v2: fix llvm6 build, inline emit function, handle multiple targets
in one thread
v3: rebase and port onto new structure
v4: rename some vars (Bas)
v5: drag all code into radv for now, we can refactor it out later
for radeonsi if we make it shareable
v6: use a bit more C++ in the wrapper
---
 src/amd/vulkan/Makefile.sources     |   1 +
 src/amd/vulkan/radv_debug.h         |   1 +
 src/amd/vulkan/radv_device.c        |   1 +
 src/amd/vulkan/radv_llvm_helper.cpp | 165 ++++++++++++++++++++++++++++
 src/amd/vulkan/radv_nir_to_llvm.c   |   5 +-
 src/amd/vulkan/radv_shader.c        |  10 +-
 src/amd/vulkan/radv_shader_helper.h |  45 ++++++++
 7 files changed, 223 insertions(+), 5 deletions(-)
 create mode 100644 src/amd/vulkan/radv_llvm_helper.cpp
 create mode 100644 src/amd/vulkan/radv_shader_helper.h

diff --git a/src/amd/vulkan/Makefile.sources b/src/amd/vulkan/Makefile.sources
index 70d56e88cb3..1e970599e83 100644
--- a/src/amd/vulkan/Makefile.sources
+++ b/src/amd/vulkan/Makefile.sources
@@ -54,6 +54,7 @@ VULKAN_FILES := \
 	radv_meta_resolve_cs.c \
 	radv_meta_resolve_fs.c \
 	radv_nir_to_llvm.c \
+	radv_llvm_helper.cpp \
 	radv_pass.c \
 	radv_pipeline.c \
 	radv_pipeline_cache.c \
diff --git a/src/amd/vulkan/radv_debug.h b/src/amd/vulkan/radv_debug.h
index f1b0dc26a63..9fe4c3b7404 100644
--- a/src/amd/vulkan/radv_debug.h
+++ b/src/amd/vulkan/radv_debug.h
@@ -49,6 +49,7 @@ enum {
 	RADV_DEBUG_ERRORS            = 0x80000,
 	RADV_DEBUG_STARTUP           = 0x100000,
 	RADV_DEBUG_CHECKIR           = 0x200000,
+	RADV_DEBUG_NOTHREADLLVM      = 0x400000,
 };
 
 enum {
diff --git a/src/amd/vulkan/radv_device.c b/src/amd/vulkan/radv_device.c
index ad3465f594e..73c48cef1f0 100644
--- a/src/amd/vulkan/radv_device.c
+++ b/src/amd/vulkan/radv_device.c
@@ -436,6 +436,7 @@ static const struct debug_control radv_debug_options[] = {
 	{"errors", RADV_DEBUG_ERRORS},
 	{"startup", RADV_DEBUG_STARTUP},
 	{"checkir", RADV_DEBUG_CHECKIR},
+	{"nothreadllvm", RADV_DEBUG_NOTHREADLLVM},
 	{NULL, 0}
 };
 
diff --git a/src/amd/vulkan/radv_llvm_helper.cpp b/src/amd/vulkan/radv_llvm_helper.cpp
new file mode 100644
index 00000000000..2d763650f8a
--- /dev/null
+++ b/src/amd/vulkan/radv_llvm_helper.cpp
@@ -0,0 +1,165 @@
+/*
+ * Copyright © 2018 Red Hat.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+#include "ac_llvm_util.h"
+#include "ac_llvm_build.h"
+#include "radv_shader_helper.h"
+#include <llvm-c/Core.h>
+#include <llvm-c/Support.h>
+#include <llvm/Target/TargetMachine.h>
+#include <llvm/Analysis/TargetLibraryInfo.h>
+#include <llvm/IR/LegacyPassManager.h>
+#if HAVE_LLVM >= 0x0700
+#include <llvm-c/Transforms/Utils.h>
+#endif
+#if HAVE_LLVM < 0x0700
+#include "llvm/Support/raw_ostream.h"
+#endif
+
+class radv_llvm_per_thread_info {
+public:
+	radv_llvm_per_thread_info(enum radeon_family arg_family,
+				enum ac_target_machine_options arg_tm_options)
+		: family(arg_family), tm_options(arg_tm_options),
+		  ostream(code_string) {}
+	~radv_llvm_per_thread_info()
+	{
+		ac_destroy_llvm_compiler(&llvm_info);
+	}
+
+	bool init(void)
+	{
+		if (ac_init_llvm_compiler(&llvm_info,
+					  true,
+					  family,
+					  tm_options))
+			return false;
+
+		llvm::TargetMachine *TM = reinterpret_cast<llvm::TargetMachine*>(llvm_info.tm);
+		if (TM->addPassesToEmitFile(pass, ostream,
+#if HAVE_LLVM >= 0x0700
+					    nullptr,
+#endif
+					    llvm::TargetMachine::CGFT_ObjectFile)) {
+			assert(0);
+			return false;
+		}
+		return true;
+	}
+
+	void compile_to_memory_buffer(LLVMModuleRef module,
+				      char **error_message,
+				      LLVMMemoryBufferRef *out_mem_buf)
+	{
+		llvm::TargetMachine *tm = reinterpret_cast<llvm::TargetMachine*>(llvm_info.tm);
+		llvm::Module *llvm_mod = llvm::unwrap(module);
+		llvm::StringRef data;
+
+		llvm_mod->setDataLayout(tm->createDataLayout());
+
+		pass.run(*llvm_mod);
+
+		data = ostream.str();
+		*out_mem_buf = LLVMCreateMemoryBufferWithMemoryRangeCopy(data.data(), data.size(), "");
+		code_string = "";
+	}
+
+	bool is_same(enum radeon_family arg_family,
+		     enum ac_target_machine_options arg_tm_options) {
+		if (arg_family == family &&
+		    arg_tm_options == tm_options)
+			return true;
+		return false;
+	}
+	struct ac_llvm_compiler llvm_info;
+private:
+	enum radeon_family family;
+	enum ac_target_machine_options tm_options;
+	llvm::SmallString<0> code_string;
+	llvm::raw_svector_ostream ostream;
+	llvm::legacy::PassManager pass;
+};
+
+/* we have to store a linked list per thread due to the possiblity of multiple gpus being required */
+static thread_local std::list<radv_llvm_per_thread_info> radv_llvm_per_thread_list;
+
+bool radv_compile_to_memory_buffer(struct ac_llvm_compiler *info,
+				   LLVMModuleRef module,
+				   char **error_message,
+				   LLVMMemoryBufferRef *out_mem_buf)
+{
+	radv_llvm_per_thread_info *thread_info = nullptr;
+
+	for (auto &I : radv_llvm_per_thread_list) {
+		if (I.llvm_info.tm == info->tm) {
+			thread_info = &I;
+			break;
+		}
+	}
+
+	if (!thread_info) {
+		return LLVMTargetMachineEmitToMemoryBuffer(info->tm, module, LLVMObjectFile,
+							   error_message, out_mem_buf);
+	}
+
+	thread_info->compile_to_memory_buffer(module, error_message, out_mem_buf);
+	return false;
+}
+
+bool radv_init_llvm_compiler(struct ac_llvm_compiler *info,
+			     bool okay_to_leak_target_library_info,
+			     bool thread_compiler,
+			     enum radeon_family family,
+			     enum ac_target_machine_options tm_options)
+{
+	if (thread_compiler) {
+		for (auto &I : radv_llvm_per_thread_list) {
+			if (I.is_same(family, tm_options)) {
+				*info = I.llvm_info;
+				return true;
+			}
+		}
+
+		radv_llvm_per_thread_list.emplace_back(family, tm_options);
+		radv_llvm_per_thread_info &tinfo = radv_llvm_per_thread_list.back();
+
+		if (tinfo.init())
+			return false;
+
+		*info = tinfo.llvm_info;
+		return true;
+	}
+
+	if (!ac_init_llvm_compiler(info,
+				   okay_to_leak_target_library_info,
+				   family,
+				   tm_options))
+		return false;
+	return true;
+}
+
+void radv_destroy_llvm_compiler(struct ac_llvm_compiler *info,
+				bool thread_compiler)
+{
+	if (thread_compiler)
+		ac_destroy_llvm_compiler(info);
+}
diff --git a/src/amd/vulkan/radv_nir_to_llvm.c b/src/amd/vulkan/radv_nir_to_llvm.c
index 45ac0854c17..76a6f1ea6da 100644
--- a/src/amd/vulkan/radv_nir_to_llvm.c
+++ b/src/amd/vulkan/radv_nir_to_llvm.c
@@ -27,6 +27,7 @@
 
 #include "radv_private.h"
 #include "radv_shader.h"
+#include "radv_shader_helper.h"
 #include "nir/nir.h"
 
 #include <llvm-c/Core.h>
@@ -3343,8 +3344,8 @@ static unsigned ac_llvm_compile(LLVMModuleRef M,
 	                                &retval);
 
 	/* Compile IR*/
-	mem_err = LLVMTargetMachineEmitToMemoryBuffer(ac_llvm->tm, M, LLVMObjectFile,
-	                                              &err, &out_buffer);
+	mem_err = radv_compile_to_memory_buffer(ac_llvm, M,
+						&err, &out_buffer);
 
 	/* Process Errors/Warnings */
 	if (mem_err) {
diff --git a/src/amd/vulkan/radv_shader.c b/src/amd/vulkan/radv_shader.c
index 5cca761d89e..13990059985 100644
--- a/src/amd/vulkan/radv_shader.c
+++ b/src/amd/vulkan/radv_shader.c
@@ -30,6 +30,7 @@
 #include "radv_debug.h"
 #include "radv_private.h"
 #include "radv_shader.h"
+#include "radv_shader_helper.h"
 #include "nir/nir.h"
 #include "nir/nir_builder.h"
 #include "spirv/nir_spirv.h"
@@ -542,7 +543,7 @@ shader_variant_create(struct radv_device *device,
 	struct radv_shader_variant *variant;
 	struct ac_shader_binary binary;
 	struct ac_llvm_compiler ac_llvm;
-
+	bool thread_compiler;
 	variant = calloc(1, sizeof(struct radv_shader_variant));
 	if (!variant)
 		return NULL;
@@ -564,8 +565,11 @@ shader_variant_create(struct radv_device *device,
 	if (options->check_ir)
 		tm_options |= AC_TM_CHECK_IR;
 
+	thread_compiler = !(device->instance->debug_flags & RADV_DEBUG_NOTHREADLLVM);
 	radv_init_llvm_once();
-	ac_init_llvm_compiler(&ac_llvm, false, chip_family, tm_options);
+	radv_init_llvm_compiler(&ac_llvm, false,
+				thread_compiler,
+				chip_family, tm_options);
 	if (gs_copy_shader) {
 		assert(shader_count == 1);
 		radv_compile_gs_copy_shader(&ac_llvm, *shaders, &binary,
@@ -577,7 +581,7 @@ shader_variant_create(struct radv_device *device,
 					options);
 	}
 
-	ac_destroy_llvm_compiler(&ac_llvm);
+	radv_destroy_llvm_compiler(&ac_llvm, thread_compiler);
 
 	radv_fill_shader_variant(device, variant, &binary, stage);
 
diff --git a/src/amd/vulkan/radv_shader_helper.h b/src/amd/vulkan/radv_shader_helper.h
new file mode 100644
index 00000000000..c90c4cca7cb
--- /dev/null
+++ b/src/amd/vulkan/radv_shader_helper.h
@@ -0,0 +1,45 @@
+/*
+ * Copyright © 2018 Red Hat.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+#ifndef RADV_SHADER_HELPER_H
+#define RADV_SHADER_HELPER_H
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+bool radv_init_llvm_compiler(struct ac_llvm_compiler *info,
+			     bool okay_to_leak_target_library_info,
+			     bool thread_compiler,
+			     enum radeon_family family,
+			     enum ac_target_machine_options tm_options);
+void radv_destroy_llvm_compiler(struct ac_llvm_compiler *info,
+				bool thread_compiler);
+
+bool radv_compile_to_memory_buffer(struct ac_llvm_compiler *info,
+				   LLVMModuleRef module,
+				   char **error_message,
+				   LLVMMemoryBufferRef *out_mem_buf);
+
+#ifdef __cplusplus
+}
+#endif
+#endif
-- 
2.17.1



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