printf

1
2
3

#include "kernel_operator.h"
AscendC::printf("fmt string %d\n", 0x123);
AscendC::PRINTF("fmt string %d\n", 0x123);

The printing function of printf (PRINTF) affects the actual running performance of the operator. Therefore, this function is usually used in the commissioning phase. Developers can disable the printing function in either of the following ways:

• Custom operator project
  Modify the CMakeLists.txt file in the op_kernel directory of the operator project. Add the compilation option -DASCENDC_DUMP=0 to the first line to disable ASCENDC_DUMP. The following is an example.

  1 2	// Disable the printf printing function of all operators. add_ops_compile_options(ALL OPTIONS -DASCENDC_DUMP=0)

• Kernel launch project
  • Modify the npu_lib.cmake file in the cmake directory. Add the -DASCENDC_DUMP=0 macro definition to the ascendc_compile_definitions command to disable the ASCENDC_DUMP function on the NPU. The following is an example.

    1 2 3 4

    // Disable the printf printing function of all operators. ascendc_compile_definitions(ascendc_kernels_${RUN_MODE} PRIVATE -DASCENDC_DUMP=0 )

  • Modify the cpu_lib.cmake file in the cmake directory. Add the -DASCENDC_DUMP=0 macro definition to the target_compile_definitions command to disable the ASCENDC_DUMP switch on the CPU. The following is an example.

    1 2 3

    target_compile_definitions(ascendc_kernels_${RUN_MODE} PRIVATE -DASCENDC_DUMP=0 )

    Note that disabling the printing function on the CPU takes effect only for PRINTF and does not take effect for printf.

1
2
3

CANN Version: XXX.XX, TimeStamp: 20240807140556417
fmt string 291
fmt string 291

The way of outputting the printf result varies according to the operator execution mode. In the dynamic graph or single-operator scenario, the content to be output is parsed and printed on the screen. In the static graph scenario, all operators of the graph need to be offloaded to the NPU for execution, and the information about a single operator cannot be printed by directly calling the API. In this case, after the model is executed, the content to be output needs to be flushed to the dump file, which is further parsed into readable content by using a tool.

• The dump file paths are sorted by priority as follows:
  • If the data dump function is enabled, the dump file is stored in dump_path configured by the developer. Dump function enabling depends on the network run mode. The following uses TensorFlow online inference as an example to describe how to configure parameters such as enable_dump, dump_path, and dump_mode. For details about how to configure them, see API Reference > TF Adapter API (2.x) > npu.global_options > Configuration Options in TensorFlow 2.6.5 Model Porting Guide.
  • If the data dump function is disabled but the ASCEND_WORK_PATH environment variable is configured, the dump file is flushed to the printf directory in ASCEND_WORK_PATH. For details about how to configure the ASCEND_WORK_PATH environment variable, see ASCEND_WORK_PATH.
  • If the data dump function is disabled and the ASCEND_WORK_PATH environment variable is not configured, the dump file is flushed to the printf directory in the current execution directory.
• The dump file needs to be parsed into readable content by using a tool.
  The show_kernel_debug_data tool can be used to parse a dump binary file into readable content. The command format is as follows: For details about how to use show_kernel_debug_data, see show_kernel_debug_data.

  show_kernel_debug_data  bin_file  output_dir

1
2

void printf(__gm__ const char* fmt, Args&&... args)
void PRINTF(__gm__ const char* fmt, Args&&... args)

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15

#include "kernel_operator.h"

// Integer printing:
AscendC::printf("fmt string %d\n", 0x123);
AscendC::PRINTF("fmt string %d\n", 0x123);

// Floating-point printing:
float a = 3.14;
AscendC::printf("fmt string %f\n", a);
AscendC::PRINTF("fmt string %f\n", a);

// Pointer printing:
int *a;
AscendC::printf("TEST %p\n", a);
AscendC::PRINTF("TEST %p\n", a);

1
2
3
4
5
6

fmt string 291
fmt string 291
fmt string 3.14
fmt string 3.14
TEST 0x12c08001a000
TEST 0x12c08001a000