runtime: refactor os-specific code

thread_GOOS.c becomes os_GOOS.c.

signal_GOOS_GOARCH.c becomes os_GOOS_GOARCH.c,
but with non-GOARCH-specific code moved into os_GOOS.c.

The actual arch-specific signal handler moves into signal_GOARCH.c
to avoid per-GOOS duplication.

New files signal_GOOS_GOARCH.h provide macros for
accessing fields of the very system-specific signal info structs.

Lots moving, but nothing changing.
This is a preliminarly cleanup so I can work on the signal
handling code to fix some open issues without having to
make each change 13 times.

Tested on Linux and OS X, 386 and amd64.
Will fix Plan 9, Windows, and ARM after the fact if necessary.
(Plan 9 and Windows should be fine; ARM will probably have some typos.)

Net effect: -1081 lines of code.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/7565048

1 files changed, 0 insertions, 311 deletions

diff --git a/src/pkg/runtime/thread_linux.c b/src/pkg/runtime/thread_linux.c
deleted file mode 100644
index 7fdc757dfc..0000000000
--- a/src/pkg/runtime/thread_linux.c
+++ /dev/null
@@ -1,311 +0,0 @@
-// 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 "runtime.h"
-#include "defs_GOOS_GOARCH.h"
-#include "os_GOOS.h"
-#include "stack.h"
-
-extern SigTab runtime·sigtab[];
-
-static Sigset sigset_none;
-static Sigset sigset_all = { ~(uint32)0, ~(uint32)0 };
-
-// Linux futex.
-//
-//	futexsleep(uint32 *addr, uint32 val)
-//	futexwakeup(uint32 *addr)
-//
-// Futexsleep atomically checks if *addr == val and if so, sleeps on addr.
-// Futexwakeup wakes up threads sleeping on addr.
-// Futexsleep is allowed to wake up spuriously.
-
-enum
-{
-	FUTEX_WAIT = 0,
-	FUTEX_WAKE = 1,
-};
-
-// Atomically,
-//	if(*addr == val) sleep
-// Might be woken up spuriously; that's allowed.
-// Don't sleep longer than ns; ns < 0 means forever.
-void
-runtime·futexsleep(uint32 *addr, uint32 val, int64 ns)
-{
-	Timespec ts, *tsp;
-
-	if(ns < 0)
-		tsp = nil;
-	else {
-		ts.tv_sec = ns/1000000000LL;
-		ts.tv_nsec = ns%1000000000LL;
-		// Avoid overflow
-		if(ts.tv_sec > 1<<30)
-			ts.tv_sec = 1<<30;
-		tsp = &ts;
-	}
-
-	// Some Linux kernels have a bug where futex of
-	// FUTEX_WAIT returns an internal error code
-	// as an errno.  Libpthread ignores the return value
-	// here, and so can we: as it says a few lines up,
-	// spurious wakeups are allowed.
-	runtime·futex(addr, FUTEX_WAIT, val, tsp, nil, 0);
-}
-
-// If any procs are sleeping on addr, wake up at most cnt.
-void
-runtime·futexwakeup(uint32 *addr, uint32 cnt)
-{
-	int64 ret;
-
-	ret = runtime·futex(addr, FUTEX_WAKE, cnt, nil, nil, 0);
-
-	if(ret >= 0)
-		return;
-
-	// I don't know that futex wakeup can return
-	// EAGAIN or EINTR, but if it does, it would be
-	// safe to loop and call futex again.
-	runtime·printf("futexwakeup addr=%p returned %D\n", addr, ret);
-	*(int32*)0x1006 = 0x1006;
-}
-
-extern runtime·sched_getaffinity(uintptr pid, uintptr len, uintptr *buf);
-static int32
-getproccount(void)
-{
-	uintptr buf[16], t;
-	int32 r, cnt, i;
-
-	cnt = 0;
-	r = runtime·sched_getaffinity(0, sizeof(buf), buf);
-	if(r > 0)
-	for(i = 0; i < r/sizeof(buf[0]); i++) {
-		t = buf[i];
-		t = t - ((t >> 1) & 0x5555555555555555ULL);
-		t = (t & 0x3333333333333333ULL) + ((t >> 2) & 0x3333333333333333ULL);
-		cnt += (int32)((((t + (t >> 4)) & 0xF0F0F0F0F0F0F0FULL) * 0x101010101010101ULL) >> 56);
-	}
-
-	return cnt ? cnt : 1;
-}
-
-// Clone, the Linux rfork.
-enum
-{
-	CLONE_VM = 0x100,
-	CLONE_FS = 0x200,
-	CLONE_FILES = 0x400,
-	CLONE_SIGHAND = 0x800,
-	CLONE_PTRACE = 0x2000,
-	CLONE_VFORK = 0x4000,
-	CLONE_PARENT = 0x8000,
-	CLONE_THREAD = 0x10000,
-	CLONE_NEWNS = 0x20000,
-	CLONE_SYSVSEM = 0x40000,
-	CLONE_SETTLS = 0x80000,
-	CLONE_PARENT_SETTID = 0x100000,
-	CLONE_CHILD_CLEARTID = 0x200000,
-	CLONE_UNTRACED = 0x800000,
-	CLONE_CHILD_SETTID = 0x1000000,
-	CLONE_STOPPED = 0x2000000,
-	CLONE_NEWUTS = 0x4000000,
-	CLONE_NEWIPC = 0x8000000,
-};
-
-void
-runtime·newosproc(M *mp, void *stk)
-{
-	int32 ret;
-	int32 flags;
-	Sigset oset;
-
-	/*
-	 * note: strace gets confused if we use CLONE_PTRACE here.
-	 */
-	flags = CLONE_VM	/* share memory */
-		| CLONE_FS	/* share cwd, etc */
-		| CLONE_FILES	/* share fd table */
-		| CLONE_SIGHAND	/* share sig handler table */
-		| CLONE_THREAD	/* revisit - okay for now */
-		;
-
-	mp->tls[0] = mp->id;	// so 386 asm can find it
-	if(0){
-		runtime·printf("newosproc stk=%p m=%p g=%p clone=%p id=%d/%d ostk=%p\n",
-			stk, mp, mp->g0, runtime·clone, mp->id, (int32)mp->tls[0], &mp);
-	}
-
-	// Disable signals during clone, so that the new thread starts
-	// with signals disabled.  It will enable them in minit.
-	runtime·rtsigprocmask(SIG_SETMASK, &sigset_all, &oset, sizeof oset);
-	ret = runtime·clone(flags, stk, mp, mp->g0, runtime·mstart);
-	runtime·rtsigprocmask(SIG_SETMASK, &oset, nil, sizeof oset);
-
-	if(ret < 0) {
-		runtime·printf("runtime: failed to create new OS thread (have %d already; errno=%d)\n", runtime·mcount(), -ret);
-		runtime·throw("runtime.newosproc");
-	}
-}
-
-void
-runtime·osinit(void)
-{
-	runtime·ncpu = getproccount();
-}
-
-// Random bytes initialized at startup.  These come
-// from the ELF AT_RANDOM auxiliary vector (vdso_linux_amd64.c).
-byte*	runtime·startup_random_data;
-uint32	runtime·startup_random_data_len;
-
-void
-runtime·get_random_data(byte **rnd, int32 *rnd_len)
-{
-	if(runtime·startup_random_data != nil) {
-		*rnd = runtime·startup_random_data;
-		*rnd_len = runtime·startup_random_data_len;
-	} else {
-		static byte urandom_data[HashRandomBytes];
-		int32 fd;
-		fd = runtime·open("/dev/urandom", 0 /* O_RDONLY */, 0);
-		if(runtime·read(fd, urandom_data, HashRandomBytes) == HashRandomBytes) {
-			*rnd = urandom_data;
-			*rnd_len = HashRandomBytes;
-		} else {
-			*rnd = nil;
-			*rnd_len = 0;
-		}
-		runtime·close(fd);
-	}
-}
-
-void
-runtime·goenvs(void)
-{
-	runtime·goenvs_unix();
-}
-
-// Called to initialize a new m (including the bootstrap m).
-// Called on the parent thread (main thread in case of bootstrap), can allocate memory.
-void
-runtime·mpreinit(M *mp)
-{
-	mp->gsignal = runtime·malg(32*1024);	// OS X wants >=8K, Linux >=2K
-}
-
-// Called to initialize a new m (including the bootstrap m).
-// Called on the new thread, can not allocate memory.
-void
-runtime·minit(void)
-{
-	// Initialize signal handling.
-	runtime·signalstack((byte*)m->gsignal->stackguard - StackGuard, 32*1024);
-	runtime·rtsigprocmask(SIG_SETMASK, &sigset_none, nil, sizeof(Sigset));
-}
-
-// Called from dropm to undo the effect of an minit.
-void
-runtime·unminit(void)
-{
-	runtime·signalstack(nil, 0);
-}
-
-void
-runtime·sigpanic(void)
-{
-	switch(g->sig) {
-	case SIGBUS:
-		if(g->sigcode0 == BUS_ADRERR && g->sigcode1 < 0x1000) {
-			if(g->sigpc == 0)
-				runtime·panicstring("call of nil func value");
-			}
-			runtime·panicstring("invalid memory address or nil pointer dereference");
-		runtime·printf("unexpected fault address %p\n", g->sigcode1);
-		runtime·throw("fault");
-	case SIGSEGV:
-		if((g->sigcode0 == 0 || g->sigcode0 == SEGV_MAPERR || g->sigcode0 == SEGV_ACCERR) && g->sigcode1 < 0x1000) {
-			if(g->sigpc == 0)
-				runtime·panicstring("call of nil func value");
-			runtime·panicstring("invalid memory address or nil pointer dereference");
-		}
-		runtime·printf("unexpected fault address %p\n", g->sigcode1);
-		runtime·throw("fault");
-	case SIGFPE:
-		switch(g->sigcode0) {
-		case FPE_INTDIV:
-			runtime·panicstring("integer divide by zero");
-		case FPE_INTOVF:
-			runtime·panicstring("integer overflow");
-		}
-		runtime·panicstring("floating point error");
-	}
-	runtime·panicstring(runtime·sigtab[g->sig].name);
-}
-
-uintptr
-runtime·memlimit(void)
-{
-	Rlimit rl;
-	extern byte text[], end[];
-	uintptr used;
-
-	if(runtime·getrlimit(RLIMIT_AS, &rl) != 0)
-		return 0;
-	if(rl.rlim_cur >= 0x7fffffff)
-		return 0;
-
-	// Estimate our VM footprint excluding the heap.
-	// Not an exact science: use size of binary plus
-	// some room for thread stacks.
-	used = end - text + (64<<20);
-	if(used >= rl.rlim_cur)
-		return 0;
-
-	// If there's not at least 16 MB left, we're probably
-	// not going to be able to do much.  Treat as no limit.
-	rl.rlim_cur -= used;
-	if(rl.rlim_cur < (16<<20))
-		return 0;
-
-	return rl.rlim_cur - used;
-}
-
-void
-runtime·setprof(bool on)
-{
-	USED(on);
-}
-
-static int8 badcallback[] = "runtime: cgo callback on thread not created by Go.\n";
-
-// This runs on a foreign stack, without an m or a g.  No stack split.
-#pragma textflag 7
-void
-runtime·badcallback(void)
-{
-	runtime·write(2, badcallback, sizeof badcallback - 1);
-}
-
-static int8 badsignal[] = "runtime: signal received on thread not created by Go: ";
-
-// This runs on a foreign stack, without an m or a g.  No stack split.
-#pragma textflag 7
-void
-runtime·badsignal(int32 sig)
-{
-	if (sig == SIGPROF) {
-		return;  // Ignore SIGPROFs intended for a non-Go thread.
-	}
-	runtime·write(2, badsignal, sizeof badsignal - 1);
-	if (0 <= sig && sig < NSIG) {
-		// Call runtime·findnull dynamically to circumvent static stack size check.
-		static int32 (*findnull)(byte*) = runtime·findnull;
-		runtime·write(2, runtime·sigtab[sig].name, findnull((byte*)runtime·sigtab[sig].name));
-	}
-	runtime·write(2, "\n", 1);
-	runtime·exit(1);
-}