qbit/go
1
0
Fork 0
mirror of https://github.com/golang/go synced 2024-11-25 03:07:56 -07:00
Code Releases Activity

runtime/cgo: take 2

Browse Source 
This is a second attempt at submitting
https://golang.org/cl/3420043

A Mercurial problem lost the new files
in that submit.

TBR=r
CC=golang-dev
https://golang.org/cl/3511043
This commit is contained in:
Russ Cox 2010-12-08 14:10:00 -05:00
parent 14d677ecba
commit b07b04d35f
11 changed files with 705 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

67
src/pkg/runtime/cgo/386.S Executable file
View File

@ -0,0 +1,67 @@
// Copyright 2009 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.
/*
* Apple still insists on underscore prefixes for C function names.
*/
#if defined(__APPLE__) || defined(_WIN32)
#define EXT(s) _##s
#else
#define EXT(s) s
#endif
/*
* void crosscall_386(void (*fn)(void))
*
* Calling into the 8c tool chain, where all registers are caller save.
* Called from standard x86 ABI, where %ebp, %ebx, %esi,
* and %edi are callee-save, so they must be saved explicitly.
*/
.globl EXT(crosscall_386)
EXT(crosscall_386):
pushl %ebp
movl %esp, %ebp
pushl %ebx
pushl %esi
pushl %edi
movl 8(%ebp), %eax /* fn */
call *%eax
popl %edi
popl %esi
popl %ebx
popl %ebp
ret
/*
* void crosscall2(void (*fn)(void*, int32), void*, int32)
*
* Save registers and call fn with two arguments.
*/
.globl EXT(crosscall2)
EXT(crosscall2):
pushl %ebp
movl %esp, %ebp
pushl %ebx
pushl %esi
pushl %edi
pushl 16(%ebp)
pushl 12(%ebp)
mov 8(%ebp), %eax
call *%eax
addl $8,%esp
popl %edi
popl %esi
popl %ebx
popl %ebp
ret
.globl EXT(__stack_chk_fail_local)
EXT(__stack_chk_fail_local):
1:
jmp 1b

35
src/pkg/runtime/cgo/Makefile Normal file
View File

@ -0,0 +1,35 @@
# Copyright 2010 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.
include ../../../Make.inc
TARG=runtime/cgo
GOFILES=\
cgo.go\
# Unwarranted chumminess with Make.pkg's cgo rules.
# Do not try this at home.
GCC_OFILES=\
$(GOARCH).o\
$(GOOS)_$(GOARCH).o\
util.o\
OFILES=\
iscgo.$O\
_cgo_import.$O\
$(GCC_OFILES)\
CGO_LDFLAGS=-lpthread
include ../../../Make.pkg
$(GOARCH).o: $(GOARCH).S
$(HOST_CC) $(_CGO_CFLAGS_$(GOARCH)) -g -O2 -fPIC -o $@ -c $^
$(GOOS)_$(GOARCH).o: $(GOOS)_$(GOARCH).c
$(HOST_CC) $(_CGO_CFLAGS_$(GOARCH)) -g -O2 -fPIC -o $@ -c $^
%.o: %.c
$(HOST_CC) $(_CGO_CFLAGS_$(GOARCH)) -g -O2 -fPIC -o $@ -c $^

73
src/pkg/runtime/cgo/amd64.S Normal file
View File

@ -0,0 +1,73 @@
// Copyright 2009 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.
/*
* Apple still insists on underscore prefixes for C function names.
*/
#if defined(__APPLE__) || defined(_WIN32)
#define EXT(s) _##s
#else
#define EXT(s) s
#endif
/*
* void crosscall_amd64(void (*fn)(void))
*
* Calling into the 6c tool chain, where all registers are caller save.
* Called from standard x86-64 ABI, where %rbx, %rbp, %r12-%r15
* are callee-save so they must be saved explicitly.
* The standard x86-64 ABI passes the three arguments m, g, fn
* in %rdi, %rsi, %rdx.
*
* Also need to set %r15 to g and %r14 to m (see ../pkg/runtime/mkasmh.sh)
* during the call.
*/
.globl EXT(crosscall_amd64)
EXT(crosscall_amd64):
pushq %rbx
pushq %rbp
pushq %r12
pushq %r13
pushq %r14
pushq %r15
call *%rdi /* fn */
popq %r15
popq %r14
popq %r13
popq %r12
popq %rbp
popq %rbx
ret
/*
* void crosscall2(void (*fn)(void*, int32), void *arg, int32 argsize)
*
* Save registers and call fn with two arguments. fn is a Go function
* which takes parameters on the stack rather than in registers.
*/
.globl EXT(crosscall2)
EXT(crosscall2):
subq $0x58, %rsp /* keeps stack pointer 32-byte aligned */
movq %rbx, 0x10(%rsp)
movq %rbp, 0x18(%rsp)
movq %r12, 0x20(%rsp)
movq %r13, 0x28(%rsp)
movq %r14, 0x30(%rsp)
movq %r15, 0x38(%rsp)
movq %rsi, 0(%rsp) /* arg */
movq %rdx, 8(%rsp) /* argsize (includes padding) */
call *%rdi /* fn */
movq 0x10(%rsp), %rbx
movq 0x18(%rsp), %rbp
movq 0x20(%rsp), %r12
movq 0x28(%rsp), %r13
movq 0x30(%rsp), %r14
movq 0x38(%rsp), %r15
addq $0x58, %rsp
ret

10
src/pkg/runtime/cgo/cgo.go Normal file
View File

@ -0,0 +1,10 @@
// Copyright 2010 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.
/*
Package cgo contains runtime support for code generated
by the cgo tool. See the documentation for the cgo command
for details on using cgo.
*/
package cgo

144
src/pkg/runtime/cgo/darwin_386.c Normal file
View File

@ -0,0 +1,144 @@
// Copyright 2009 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.
#include <pthread.h>
#include "libcgo.h"
static void* threadentry(void*);
static pthread_key_t k1, k2;
static void
inittls(void)
{
uint32 x, y;
pthread_key_t tofree[16], k;
int i, ntofree;
int havek1, havek2;
/*
* Allocate thread-local storage slots for m, g.
* The key numbers start at 0x100, and we expect to be
* one of the early calls to pthread_key_create, so we
* should be able to get pretty low numbers.
*
* In Darwin/386 pthreads, %gs points at the thread
* structure, and each key is an index into the thread-local
* storage array that begins at offset 0x48 within in that structure.
* It may happen that we are not quite the first function to try
* to allocate thread-local storage keys, so instead of depending
* on getting 0x100 and 0x101, we try for 0x108 and 0x109,
* allocating keys until we get the ones we want and then freeing
* the ones we didn't want.
*
* Thus the final offsets to use in %gs references are
* 0x48+4*0x108 = 0x468 and 0x48+4*0x109 = 0x46c.
*
* The linker and runtime hard-code these constant offsets
* from %gs where we expect to find m and g. The code
* below verifies that the constants are correct once it has
* obtained the keys. Known to ../cmd/8l/obj.c:/468
* and to ../pkg/runtime/darwin/386/sys.s:/468
*
* This is truly disgusting and a bit fragile, but taking care
* of it here protects the rest of the system from damage.
* The alternative would be to use a global variable that
* held the offset and refer to that variable each time we
* need a %gs variable (m or g). That approach would
* require an extra instruction and memory reference in
* every stack growth prolog and would also require
* rewriting the code that 8c generates for extern registers.
*/
havek1 = 0;
havek2 = 0;
ntofree = 0;
while(!havek1 || !havek2) {
if(pthread_key_create(&k, nil) < 0) {
fprintf(stderr, "libcgo: pthread_key_create failed\n");
abort();
}
if(k == 0x108) {
havek1 = 1;
k1 = k;
continue;
}
if(k == 0x109) {
havek2 = 1;
k2 = k;
continue;
}
if(ntofree >= nelem(tofree)) {
fprintf(stderr, "libcgo: could not obtain pthread_keys\n");
fprintf(stderr, "\twanted 0x108 and 0x109\n");
fprintf(stderr, "\tgot");
for(i=0; i<ntofree; i++)
fprintf(stderr, " %#lx", tofree[i]);
fprintf(stderr, "\n");
abort();
}
tofree[ntofree++] = k;
}
for(i=0; i<ntofree; i++)
pthread_key_delete(tofree[i]);
/*
* We got the keys we wanted. Make sure that we observe
* updates to k1 at 0x468, to verify that the TLS array
* offset from %gs hasn't changed.
*/
pthread_setspecific(k1, (void*)0x12345678);
asm volatile("movl %%gs:0x468, %0" : "=r"(x));
pthread_setspecific(k1, (void*)0x87654321);
asm volatile("movl %%gs:0x468, %0" : "=r"(y));
if(x != 0x12345678 || y != 0x87654321) {
printf("libcgo: thread-local storage %#lx not at %%gs:0x468 - x=%#x y=%#x\n", k1, x, y);
abort();
}
}
static void
xinitcgo(void)
{
inittls();
}
void (*initcgo)(void) = xinitcgo;
void
libcgo_sys_thread_start(ThreadStart *ts)
{
pthread_attr_t attr;
pthread_t p;
size_t size;
pthread_attr_init(&attr);
pthread_attr_getstacksize(&attr, &size);
ts->g->stackguard = size;
pthread_create(&p, &attr, threadentry, ts);
}
static void*
threadentry(void *v)
{
ThreadStart ts;
ts = *(ThreadStart*)v;
free(v);
ts.g->stackbase = (uintptr)&ts;
/*
* libcgo_sys_thread_start set stackguard to stack size;
* change to actual guard pointer.
*/
ts.g->stackguard = (uintptr)&ts - ts.g->stackguard + 4096;
pthread_setspecific(k1, (void*)ts.g);
pthread_setspecific(k2, (void*)ts.m);
crosscall_386(ts.fn);
return nil;
}

125
src/pkg/runtime/cgo/darwin_amd64.c Normal file
View File

@ -0,0 +1,125 @@
// Copyright 2009 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.
#include <pthread.h>
#include "libcgo.h"
static void* threadentry(void*);
static pthread_key_t k1, k2;
static void
inittls(void)
{
uint64 x, y;
pthread_key_t tofree[16], k;
int i, ntofree;
int havek1, havek2;
/*
* Same logic, code as darwin_386.c:/inittls, except that words
* are 8 bytes long now, and the thread-local storage starts at 0x60.
* So the offsets are
* 0x60+8*0x108 = 0x8a0 and 0x60+8*0x109 = 0x8a8.
*
* The linker and runtime hard-code these constant offsets
* from %gs where we expect to find m and g. The code
* below verifies that the constants are correct once it has
* obtained the keys. Known to ../cmd/6l/obj.c:/8a0
* and to ../pkg/runtime/darwin/amd64/sys.s:/8a0
*
* As disgusting as on the 386; same justification.
*/
havek1 = 0;
havek2 = 0;
ntofree = 0;
while(!havek1 || !havek2) {
if(pthread_key_create(&k, nil) < 0) {
fprintf(stderr, "libcgo: pthread_key_create failed\n");
abort();
}
if(k == 0x108) {
havek1 = 1;
k1 = k;
continue;
}
if(k == 0x109) {
havek2 = 1;
k2 = k;
continue;
}
if(ntofree >= nelem(tofree)) {
fprintf(stderr, "libcgo: could not obtain pthread_keys\n");
fprintf(stderr, "\twanted 0x108 and 0x109\n");
fprintf(stderr, "\tgot");
for(i=0; i<ntofree; i++)
fprintf(stderr, " %#x", (unsigned)tofree[i]);
fprintf(stderr, "\n");
abort();
}
tofree[ntofree++] = k;
}
for(i=0; i<ntofree; i++)
pthread_key_delete(tofree[i]);
/*
* We got the keys we wanted. Make sure that we observe
* updates to k1 at 0x8a0, to verify that the TLS array
* offset from %gs hasn't changed.
*/
pthread_setspecific(k1, (void*)0x123456789abcdef0ULL);
asm volatile("movq %%gs:0x8a0, %0" : "=r"(x));
pthread_setspecific(k2, (void*)0x0fedcba987654321);
asm volatile("movq %%gs:0x8a8, %0" : "=r"(y));
if(x != 0x123456789abcdef0ULL || y != 0x0fedcba987654321) {
printf("libcgo: thread-local storage %#x not at %%gs:0x8a0 - x=%#llx y=%#llx\n", (unsigned)k1, x, y);
abort();
}
}
void
xinitcgo(void)
{
inittls();
}
void (*initcgo) = xinitcgo;
void
libcgo_sys_thread_start(ThreadStart *ts)
{
pthread_attr_t attr;
pthread_t p;
size_t size;
pthread_attr_init(&attr);
pthread_attr_getstacksize(&attr, &size);
ts->g->stackguard = size;
pthread_create(&p, &attr, threadentry, ts);
}
static void*
threadentry(void *v)
{
ThreadStart ts;
ts = *(ThreadStart*)v;
free(v);
ts.g->stackbase = (uintptr)&ts;
/*
* libcgo_sys_thread_start set stackguard to stack size;
* change to actual guard pointer.
*/
ts.g->stackguard = (uintptr)&ts - ts.g->stackguard + 4096;
pthread_setspecific(k1, (void*)ts.g);
pthread_setspecific(k2, (void*)ts.m);
crosscall_amd64(ts.fn);
return nil;
}

14
src/pkg/runtime/cgo/iscgo.c Normal file
View File

@ -0,0 +1,14 @@
// Copyright 2010 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.
// The runtime package contains an uninitialized definition
// for runtime·iscgo. Override it to tell the runtime we're here.
// There are various function pointers that should be set too,
// but those depend on dynamic linker magic to get initialized
// correctly, and sometimes they break. This variable is a
// backup: it depends only on old C style static linking rules.
#include "../runtime.h"
bool runtime·iscgo = 1;

60
src/pkg/runtime/cgo/libcgo.h Normal file
View File

@ -0,0 +1,60 @@
// Copyright 2009 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.
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#define nil ((void*)0)
#define nelem(x) (sizeof(x)/sizeof((x)[0]))
typedef uint32_t uint32;
typedef uint64_t uint64;
typedef uintptr_t uintptr;
/*
* The beginning of the per-goroutine structure,
* as defined in ../pkg/runtime/runtime.h.
* Just enough to edit these two fields.
*/
typedef struct G G;
struct G
{
uintptr stackguard;
uintptr stackbase;
};
/*
* Arguments to the libcgo_thread_start call.
* Also known to ../pkg/runtime/runtime.h.
*/
typedef struct ThreadStart ThreadStart;
struct ThreadStart
{
uintptr m;
G *g;
void (*fn)(void);
};
/*
* Called by 5c/6c/8c world.
* Makes a local copy of the ThreadStart and
* calls libcgo_sys_thread_start(ts).
*/
void (*libcgo_thread_start)(ThreadStart *ts);
/*
* Creates the new operating system thread (OS, arch dependent).
*/
void libcgo_sys_thread_start(ThreadStart *ts);
/*
* Call fn in the 6c world.
*/
void crosscall_amd64(void (*fn)(void));
/*
* Call fn in the 8c world.
*/
void crosscall_386(void (*fn)(void));

68
src/pkg/runtime/cgo/linux_386.c Normal file
View File

@ -0,0 +1,68 @@
// Copyright 2009 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.
#include <pthread.h>
#include <string.h>
#include "libcgo.h"
static void *threadentry(void*);
static void
xinitcgo(void)
{
}
void (*initcgo) = xinitcgo;
void
libcgo_sys_thread_start(ThreadStart *ts)
{
pthread_attr_t attr;
pthread_t p;
size_t size;
// Not sure why the memset is necessary here,
// but without it, we get a bogus stack size
// out of pthread_attr_getstacksize. C'est la Linux.
memset(&attr, 0, sizeof attr);
pthread_attr_init(&attr);
size = 0;
pthread_attr_getstacksize(&attr, &size);
ts->g->stackguard = size;
pthread_create(&p, &attr, threadentry, ts);
}
static void*
threadentry(void *v)
{
ThreadStart ts;
ts = *(ThreadStart*)v;
free(v);
ts.g->stackbase = (uintptr)&ts;
/*
* libcgo_sys_thread_start set stackguard to stack size;
* change to actual guard pointer.
*/
ts.g->stackguard = (uintptr)&ts - ts.g->stackguard + 4096;
/*
* Set specific keys. On Linux/ELF, the thread local storage
* is just before %gs:0. Our dynamic 8.out's reserve 8 bytes
* for the two words g and m at %gs:-8 and %gs:-4.
* Xen requires us to access those words indirect from %gs:0
* which points at itself.
*/
asm volatile (
"movl %%gs:0, %%eax\n" // MOVL 0(GS), tmp
"movl %0, -8(%%eax)\n" // MOVL g, -8(GS)
"movl %1, -4(%%eax)\n" // MOVL m, -4(GS)
:: "r"(ts.g), "r"(ts.m) : "%eax"
);
crosscall_386(ts.fn);
return nil;
}

58
src/pkg/runtime/cgo/linux_amd64.c Normal file
View File

@ -0,0 +1,58 @@
// Copyright 2009 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.
#include <pthread.h>
#include "libcgo.h"
static void* threadentry(void*);
void
xinitcgo(void)
{
}
void (*initcgo)(void) = xinitcgo;
void
libcgo_sys_thread_start(ThreadStart *ts)
{
pthread_attr_t attr;
pthread_t p;
size_t size;
pthread_attr_init(&attr);
pthread_attr_getstacksize(&attr, &size);
ts->g->stackguard = size;
pthread_create(&p, &attr, threadentry, ts);
}
static void*
threadentry(void *v)
{
ThreadStart ts;
ts = *(ThreadStart*)v;
free(v);
ts.g->stackbase = (uintptr)&ts;
/*
* libcgo_sys_thread_start set stackguard to stack size;
* change to actual guard pointer.
*/
ts.g->stackguard = (uintptr)&ts - ts.g->stackguard + 4096;
/*
* Set specific keys. On Linux/ELF, the thread local storage
* is just before %fs:0. Our dynamic 6.out's reserve 16 bytes
* for the two words g and m at %fs:-16 and %fs:-8.
*/
asm volatile (
"movq %0, %%fs:-16\n" // MOVL g, -16(FS)
"movq %1, %%fs:-8\n" // MOVL m, -8(FS)
:: "r"(ts.g), "r"(ts.m)
);
crosscall_amd64(ts.fn);
return nil;
}

51
src/pkg/runtime/cgo/util.c Normal file
View File

@ -0,0 +1,51 @@
// Copyright 2009 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.
#include "libcgo.h"
/* Stub for calling malloc from Go */
static void
x_cgo_malloc(void *p)
{
struct a {
long long n;
void *ret;
} *a = p;
a->ret = malloc(a->n);
}
void (*_cgo_malloc)(void*) = x_cgo_malloc;
/* Stub for calling from Go */
static void
x_cgo_free(void *p)
{
struct a {
void *arg;
} *a = p;
free(a->arg);
}
void (*_cgo_free)(void*) = x_cgo_free;
/* Stub for creating a new thread */
static void
xlibcgo_thread_start(ThreadStart *arg)
{
ThreadStart *ts;
/* Make our own copy that can persist after we return. */
ts = malloc(sizeof *ts);
if(ts == nil) {
fprintf(stderr, "libcgo: out of memory in thread_start\n");
abort();
}
*ts = *arg;
libcgo_sys_thread_start(ts); /* OS-dependent half */
}
void (*libcgo_thread_start)(ThreadStart*) = xlibcgo_thread_start;