Modify the code based on review comment

ggml/include/ggml-cann.h

@@ -22,6 +22,9 @@
 
 #pragma once
 
+#define GGML_COMMON_DECL_C
+
+#include "../src/ggml-common.h"
 #include "ggml-backend.h"
 #include "ggml.h"
 
@@ -29,35 +32,11 @@
 extern "C" {
 #endif
 
-/**
- * @def GGML_CANN_NAME
- * @brief Define for the name of the CANN backend.
- */
-#define GGML_CANN_NAME "CANN"
-
 /**
  * @brief Maximum number of CANN devices supported.
  */
 #define GGML_CANN_MAX_DEVICES 16
 
-/**
- * @brief Structure for QK4_0 data format.
- */
-#define QK4_0 32
-typedef struct {
-    uint16_t d;            /**< Delta */
-    uint8_t qs[QK4_0 / 2]; /**< Nibbles / quants */
-} block_q4_0;
-
-/**
- * @brief Structure for QK8_0 data format.
- */
-#define QK8_0 32
-typedef struct {
-    uint16_t d;       /**< Delta */
-    int8_t qs[QK8_0]; /**< Quants */
-} block_q8_0;
-
 /**
  * @brief Initializes the CANN backend for a specified device.
  *
@@ -133,16 +112,6 @@ GGML_API GGML_CALL void ggml_backend_cann_get_device_memory(int32_t device,
                                                             size_t* free,
                                                             size_t* total);
 
-/**
- * @brief Initializes resources required by the CANN backend.
- */
-void ggml_cann_backend_init(void);
-
-/**
- * @brief Frees resources used by the CANN backend.
- */
-void ggml_cann_backend_free(void);
-
 #ifdef __cplusplus
 }
 #endif

ggml/src/ggml-cann.cpp

@@ -96,7 +96,7 @@ static ggml_cann_device_info ggml_cann_init() {
     aclError err = aclrtGetDeviceCount((uint32_t*)&info.device_count);
 
     if (err != ACL_SUCCESS) {
-        fprintf(stderr, "%s: failed to initialize " GGML_CANN_NAME ": %s\n",
+        fprintf(stderr, "%s: failed to initialize CANN: %s\n",
                 __func__, aclGetRecentErrMsg());
         return info;
     }
@@ -464,7 +464,6 @@ struct ggml_backend_cann_buffer_context {
     int32_t device;  ///< The device ID associated with this buffer context.
     void* dev_ptr =
         nullptr;  ///< Pointer to the device memory allocated for the buffer.
-    std::string name;  ///< Name of the buffer context.
 
     /**
      * @brief Constructor to initialize the CANN buffer context.
@@ -474,8 +473,7 @@ struct ggml_backend_cann_buffer_context {
      */
     ggml_backend_cann_buffer_context(int32_t device, void* dev_ptr)
         : device(device),
-          dev_ptr(dev_ptr),
+          dev_ptr(dev_ptr) {}
-          name(GGML_CANN_NAME + std::to_string(device)) {}
 
     /**
      * @brief Destructor to free the device memory allocated for the buffer.
@@ -495,9 +493,9 @@ struct ggml_backend_cann_buffer_context {
 
 GGML_CALL static const char* ggml_backend_cann_buffer_get_name(
     ggml_backend_buffer_t buffer) {
-    ggml_backend_cann_buffer_context* ctx =
+    return "CANN";
-        (ggml_backend_cann_buffer_context*)buffer->context;
+
-    return ctx->name.c_str();
+    GGML_UNUSED(buffer);
 }
 
 /**
@@ -1004,10 +1002,9 @@ struct ggml_backend_cann_buffer_type_context {
  */
 GGML_CALL static const char* ggml_backend_cann_buffer_type_name(
     ggml_backend_buffer_type_t buft) {
-    ggml_backend_cann_buffer_type_context* ctx =
+    return "CANN";
-        (ggml_backend_cann_buffer_type_context*)buft->context;
 
-    return ctx->name.c_str();
+    GGML_UNUSED(buft);
 }
 
 /**
@@ -1152,7 +1149,7 @@ ggml_backend_cann_buffer_type(int32_t device) {
                 /* .iface    = */ ggml_backend_cann_buffer_type_interface,
                 /* .context  = */
                  new ggml_backend_cann_buffer_type_context{
-                    i, GGML_CANN_NAME + std::to_string(i)},
+                    i, "CANN" + std::to_string(i)},
             };
         }
         ggml_backend_cann_buffer_type_initialized = true;
@@ -1344,6 +1341,12 @@ GGML_CALL static void ggml_backend_cann_free(ggml_backend_t backend) {
         (ggml_backend_cann_context*)backend->context;
     ACL_CHECK(aclrtSynchronizeDevice());
     ACL_CHECK(aclrtResetDevice(cann_ctx->device));
+
+    // finalize when last backend freed.
+    if (cann_ctx->device == ggml_backend_cann_get_device_count() - 1) {
+        ACL_CHECK(aclFinalize());
+    }
+
     delete cann_ctx;
     delete backend;
 }
@@ -1703,15 +1706,9 @@ static bool ggml_backend_buft_is_cann(ggml_backend_buffer_type_t buft) {
  */
 GGML_CALL static bool ggml_backend_cann_supports_buft(
     ggml_backend_t backend, ggml_backend_buffer_type_t buft) {
-    if (ggml_backend_buft_is_cann(buft)) {
+    return buft->iface.get_name == ggml_backend_cann_buffer_type_name;
-        ggml_backend_cann_context* cann_ctx =
-            (ggml_backend_cann_context*)backend->context;
-        ggml_backend_cann_buffer_type_context* buft_ctx =
-            (ggml_backend_cann_buffer_type_context*)buft->context;
-        return buft_ctx->device == cann_ctx->device;
-    }
 
-    return false;
+    GGML_UNUSED(backend);
 }
 
 /**
@@ -1870,6 +1867,7 @@ static ggml_guid_t ggml_backend_cann_guid() {
 }
 
 GGML_CALL ggml_backend_t ggml_backend_cann_init(int32_t device) {
+    aclInit(nullptr);
     if (device < 0 || device >= ggml_backend_cann_get_device_count()) {
         fprintf(stderr, "%s: error: invalid device %d\n", __func__, device);
         return nullptr;
@@ -1945,19 +1943,14 @@ extern "C" GGML_CALL int ggml_backend_cann_reg_devices();
  * @return int The number of CANN devices registered.
  */
 GGML_CALL int ggml_backend_cann_reg_devices() {
-    aclInit(nullptr);
     uint32_t device_count = ggml_backend_cann_get_device_count();
     // initialization
     for (uint32_t i = 0; i < device_count; i++) {
         char name[128];
-        snprintf(name, sizeof(name), "%s%d", GGML_CANN_NAME, i);
+        snprintf(name, sizeof(name), "CANN%d", i);
         ggml_backend_register(name, ggml_backend_reg_cann_init,
                               ggml_backend_cann_buffer_type(i),
                               (void*)(intptr_t)i);
     }
     return device_count;
 }
-
-void ggml_cann_backend_init(void) { ACL_CHECK(aclInit(nullptr)); }
-
-void ggml_cann_backend_free(void) { ACL_CHECK(aclFinalize()); }

ggml/src/ggml-cann/common.h

@@ -221,7 +221,7 @@ struct ggml_backend_cann_context {
      * @param device Device ID.
      */
     explicit ggml_backend_cann_context(int device)
-        : device(device), name(GGML_CANN_NAME + std::to_string(device)) {}
+        : device(device), name("CANN" + std::to_string(device)) {}
 
     /**
      * @brief Destructor for cleaning up resources.

src/llama.cpp

@@ -18916,10 +18916,6 @@ void llama_backend_init(void) {
         struct ggml_context * ctx = ggml_init(params);
         ggml_free(ctx);
     }
-
-#if defined(GGML_USE_CANN)
-    ggml_cann_backend_init();
-#endif
 }
 
 void llama_numa_init(enum ggml_numa_strategy numa) {
@@ -18929,10 +18925,6 @@ void llama_numa_init(enum ggml_numa_strategy numa) {
 }
 
 void llama_backend_free(void) {
-#if defined(GGML_USE_CANN)
-    ggml_cann_backend_free();
-#endif
-
     ggml_quantize_free();
 }