Revert "runtime/cgo: store M for C-created thread in pthread key"

This reverts CL 392854.

Reason for revert: caused #59294, which was derived from google
internal tests. The attempted fix of #59294 caused more breakage.

Change-Id: I5a061561ac2740856b7ecc09725ac28bd30f8bba
Reviewed-on: https://go-review.googlesource.com/c/go/+/481060
Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

1 files changed, 0 insertions, 89 deletions

diff --git a/src/runtime/testdata/testprogcgo/bindm.go b/src/runtime/testdata/testprogcgo/bindm.go
deleted file mode 100644
index ed2c6a7eea..0000000000
--- a/src/runtime/testdata/testprogcgo/bindm.go
+++ /dev/null
@@ -1,89 +0,0 @@
-// Copyright 2023 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build !plan9 && !windows
-
-// Test that callbacks from C to Go in the same C-thread always get the same m.
-// Make sure the extra M bind to the C-thread.
-
-package main
-
-/*
-#include <stdint.h>
-#include <pthread.h>
-#include <unistd.h>
-
-extern void GoCheckBindM();
-
-#define CTHREADS 2
-#define CHECKCALLS 100
-
-static void* checkBindMThread(void* thread) {
-	int i;
-	for (i = 0; i < CHECKCALLS; i++) {
-		GoCheckBindM((uintptr_t)thread);
-		usleep(1);
-	}
-	return NULL;
-}
-
-static void CheckBindM() {
-	int i;
-	pthread_t s[CTHREADS];
-
-	for (i = 0; i < CTHREADS; i++) {
-		pthread_create(&s[i], NULL, checkBindMThread, &s[i]);
-	}
-	for (i = 0; i < CTHREADS; i++) {
-		pthread_join(s[i], NULL);
-	}
-}
-*/
-import "C"
-
-import (
-	"fmt"
-	"os"
-	"runtime"
-	"sync"
-	"sync/atomic"
-)
-
-var (
-	mutex      = sync.Mutex{}
-	cThreadToM = map[uintptr]uintptr{}
-	started    = atomic.Uint32{}
-)
-
-// same as CTHREADS in C, make sure all the C threads are actually started.
-const cThreadNum = 2
-
-func init() {
-	register("EnsureBindM", EnsureBindM)
-}
-
-//export GoCheckBindM
-func GoCheckBindM(thread uintptr) {
-	// Wait all threads start
-	if started.Load() != cThreadNum {
-		// Only once for each thread, since it will wait all threads start.
-		started.Add(1)
-		for started.Load() < cThreadNum {
-			runtime.Gosched()
-		}
-	}
-	m := runtime_getm_for_test()
-	mutex.Lock()
-	defer mutex.Unlock()
-	if savedM, ok := cThreadToM[thread]; ok && savedM != m {
-		fmt.Printf("m == %x want %x\n", m, savedM)
-		os.Exit(1)
-	}
-	cThreadToM[thread] = m
-}
-
-func EnsureBindM() {
-	C.CheckBindM()
-	fmt.Println("OK")
-}