Create abstraction for pthread_once()/InitOnceExecuteOnce() calls to …

…avoid boilerplate code in many places and also to make other implementations possible.

Some (e.g.) DSP targets don't have a working version of pthreads, so we can't rely on `pthreads_once()`. This provides a single bottleneck we can use to customize for those targets (rather than dozens spread across dozens of files), and makes the code pleasantly terser.

Note that this change should be functionally a no-op, just code refactoring to make upcoming changes more seamless.

PiperOrigin-RevId: 659672037

BUILD.bazel

@@ -350,6 +350,13 @@ xnnpack_cc_library(
     ],
 )
 
+xnnpack_cc_library(
+    name = "init_once",
+    hdrs = ["src/xnnpack/init-once.h"],
+    gcc_copts = xnnpack_gcc_std_copts(),
+    msvc_copts = xnnpack_msvc_std_copts(),
+)
+
 xnnpack_cc_library(
     name = "microparams",
     hdrs = [
@@ -420,6 +427,7 @@ xnnpack_cc_library(
     msvc_copts = xnnpack_msvc_std_copts(),
     deps = [
         ":common",
+        ":init_once",
         ":logging",
     ] + select({
         ":cpuinfo_enabled": ["@cpuinfo"],
@@ -498,6 +506,7 @@ xnnpack_cc_library(
         ":enable_jit",
         ":experiments_config",
         ":hardware_config",
+        ":init_once",
         ":logging",
         ":microkernels_h",
         ":microparams_init",

src/configs/argmaxpool-config.c

@@ -6,24 +6,16 @@
 #include <assert.h>
 #include <stddef.h>
 
-#ifdef _WIN32
-  #include <windows.h>
-#else
-  #include <pthread.h>
-#endif
 
 #include "xnnpack/argmaxpool.h"
 #include "xnnpack/common.h"
 #include "xnnpack/config.h"
+#include "xnnpack/init-once.h"
 #include "xnnpack/microfnptr.h"
 
 static struct xnn_argmaxpool_config f32_argmaxpool_config[XNN_MAX_F32_ARGMAXPOOL_UKERNELS ] = {0};
 
-#if XNN_PLATFORM_WINDOWS
-  static INIT_ONCE init_guard_f32_argmaxpool = INIT_ONCE_STATIC_INIT;
-#else
-  static pthread_once_t init_guard_f32_argmaxpool = PTHREAD_ONCE_INIT;
-#endif
+XNN_INIT_ONCE_GUARD(f32_argmaxpool);
 
 static void init_f32_argmaxpool_config(void) {
   #if XNN_ARCH_ARM
@@ -117,22 +109,11 @@ static void init_f32_argmaxpool_config(void) {
   #endif
 }
 
-#if XNN_PLATFORM_WINDOWS
-  static BOOL CALLBACK init_f32_argmaxpool_config_windows(PINIT_ONCE init_once, PVOID parameter, PVOID* context) {
-    init_f32_argmaxpool_config();
-    return TRUE;
-  }
-#endif
-
 const struct xnn_argmaxpool_config* xnn_init_f32_argmaxpool_config() {
   const struct xnn_hardware_config* hardware_config = xnn_init_hardware_config();
   if (hardware_config == NULL) {
     return NULL;
   }
-  #if XNN_PLATFORM_WINDOWS
-    InitOnceExecuteOnce(&init_guard_f32_argmaxpool, &init_f32_argmaxpool_config_windows, NULL, NULL);
-  #else
-    pthread_once(&init_guard_f32_argmaxpool, &init_f32_argmaxpool_config);
-  #endif
+  XNN_INIT_ONCE(f32_argmaxpool);
   return f32_argmaxpool_config;
 }

src/configs/avgpool-config.c

@@ -6,31 +6,20 @@
 #include <assert.h>
 #include <stddef.h>
 
-#ifdef _WIN32
-  #include <windows.h>
-#else
-  #include <pthread.h>
-#endif
-
 #include "xnnpack/avgpool.h"
 #include "xnnpack/common.h"
 #include "xnnpack/config.h"
+#include "xnnpack/init-once.h"
 #include "xnnpack/microfnptr.h"
 #include "xnnpack/microparams-init.h"
 
 static struct xnn_avgpool_config f16_avgpool_config = {0};
 static struct xnn_avgpool_config f32_avgpool_config = {0};
 static struct xnn_avgpool_config qu8_avgpool_config = {0};
 
-#if XNN_PLATFORM_WINDOWS
-  static INIT_ONCE init_guard_f16_avgpool = INIT_ONCE_STATIC_INIT;
-  static INIT_ONCE init_guard_f32_avgpool = INIT_ONCE_STATIC_INIT;
-  static INIT_ONCE init_guard_qu8_avgpool = INIT_ONCE_STATIC_INIT;
-#else
-  static pthread_once_t init_guard_f16_avgpool = PTHREAD_ONCE_INIT;
-  static pthread_once_t init_guard_f32_avgpool = PTHREAD_ONCE_INIT;
-  static pthread_once_t init_guard_qu8_avgpool = PTHREAD_ONCE_INIT;
-#endif
+XNN_INIT_ONCE_GUARD(f16_avgpool);
+XNN_INIT_ONCE_GUARD(f32_avgpool);
+XNN_INIT_ONCE_GUARD(qu8_avgpool);
 
 static void init_f16_avgpool_config(void) {
   #if XNN_ARCH_ARM && XNN_ENABLE_ARM_FP16_VECTOR && XNN_ENABLE_ARM_FP16_SCALAR
@@ -187,33 +176,12 @@ static void init_qu8_avgpool_config(void) {
   #endif
 }
 
-#if XNN_PLATFORM_WINDOWS
-  static BOOL CALLBACK init_f16_avgpool_config_windows(PINIT_ONCE init_once, PVOID parameter, PVOID* context) {
-    init_f16_avgpool_config();
-    return TRUE;
-  }
-
-  static BOOL CALLBACK init_f32_avgpool_config_windows(PINIT_ONCE init_once, PVOID parameter, PVOID* context) {
-    init_f32_avgpool_config();
-    return TRUE;
-  }
-
-  static BOOL CALLBACK init_qu8_avgpool_config_windows(PINIT_ONCE init_once, PVOID parameter, PVOID* context) {
-    init_qu8_avgpool_config();
-    return TRUE;
-  }
-#endif
-
 const struct xnn_avgpool_config* xnn_init_f16_avgpool_config() {
   const struct xnn_hardware_config* hardware_config = xnn_init_hardware_config();
   if (hardware_config == NULL || !xnn_is_f16_compatible_config(hardware_config)) {
     return NULL;
   }
-  #if XNN_PLATFORM_WINDOWS
-    InitOnceExecuteOnce(&init_guard_f16_avgpool, &init_f16_avgpool_config_windows, NULL, NULL);
-  #else
-    pthread_once(&init_guard_f16_avgpool, &init_f16_avgpool_config);
-  #endif
+  XNN_INIT_ONCE(f16_avgpool);
   return &f16_avgpool_config;
 }
 
@@ -222,11 +190,7 @@ const struct xnn_avgpool_config* xnn_init_f32_avgpool_config() {
   if (hardware_config == NULL) {
     return NULL;
   }
-  #if XNN_PLATFORM_WINDOWS
-    InitOnceExecuteOnce(&init_guard_f32_avgpool, &init_f32_avgpool_config_windows, NULL, NULL);
-  #else
-    pthread_once(&init_guard_f32_avgpool, &init_f32_avgpool_config);
-  #endif
+  XNN_INIT_ONCE(f32_avgpool);
   return &f32_avgpool_config;
 }
 
@@ -235,10 +199,6 @@ const struct xnn_avgpool_config* xnn_init_qu8_avgpool_config() {
   if (hardware_config == NULL) {
     return NULL;
   }
-  #if XNN_PLATFORM_WINDOWS
-    InitOnceExecuteOnce(&init_guard_qu8_avgpool, &init_qu8_avgpool_config_windows, NULL, NULL);
-  #else
-    pthread_once(&init_guard_qu8_avgpool, &init_qu8_avgpool_config);
-  #endif
+  XNN_INIT_ONCE(qu8_avgpool);
   return &qu8_avgpool_config;
 }