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[dev.garbage] all: merge dev.cc into dev.garbage

Browse source 
The garbage collector is now written in Go.
There is plenty to clean up (just like on dev.cc).

all.bash passes on darwin/amd64, darwin/386, linux/amd64, linux/386.

TBR=rlh
R=austin, rlh, bradfitz
CC=golang-codereviews
https://golang.org/cl/173250043
This commit is contained in:
Russ Cox 2014-11-15 08:00:38 -05:00
commit 0fcf54b3d2
384 changed files with 22419 additions and 69497 deletions
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613
src/runtime/runtime2.go Normal file
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// 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.
package runtime
import "unsafe"
/*
* defined constants
*/
const (
// G status
//
// If you add to this list, add to the list
// of "okay during garbage collection" status
// in mgc0.c too.
_Gidle = iota // 0
_Grunnable // 1 runnable and on a run queue
_Grunning // 2
_Gsyscall // 3
_Gwaiting // 4
_Gmoribund_unused // 5 currently unused, but hardcoded in gdb scripts
_Gdead // 6
_Genqueue // 7 Only the Gscanenqueue is used.
_Gcopystack // 8 in this state when newstack is moving the stack
// the following encode that the GC is scanning the stack and what to do when it is done
_Gscan = 0x1000 // atomicstatus&~Gscan = the non-scan state,
// _Gscanidle = _Gscan + _Gidle, // Not used. Gidle only used with newly malloced gs
_Gscanrunnable = _Gscan + _Grunnable // 0x1001 When scanning complets make Grunnable (it is already on run queue)
_Gscanrunning = _Gscan + _Grunning // 0x1002 Used to tell preemption newstack routine to scan preempted stack.
_Gscansyscall = _Gscan + _Gsyscall // 0x1003 When scanning completes make is Gsyscall
_Gscanwaiting = _Gscan + _Gwaiting // 0x1004 When scanning completes make it Gwaiting
// _Gscanmoribund_unused, // not possible
// _Gscandead, // not possible
_Gscanenqueue = _Gscan + _Genqueue // When scanning completes make it Grunnable and put on runqueue
)
const (
// P status
_Pidle = iota
_Prunning
_Psyscall
_Pgcstop
_Pdead
)
// XXX inserting below here
type mutex struct {
// Futex-based impl treats it as uint32 key,
// while sema-based impl as M* waitm.
// Used to be a union, but unions break precise GC.
key uintptr
}
type note struct {
// Futex-based impl treats it as uint32 key,
// while sema-based impl as M* waitm.
// Used to be a union, but unions break precise GC.
key uintptr
}
type _string struct {
str *byte
len int
}
type funcval struct {
fn uintptr
// variable-size, fn-specific data here
}
type iface struct {
tab *itab
data unsafe.Pointer
}
type eface struct {
_type *_type
data unsafe.Pointer
}
type slice struct {
array *byte // actual data
len uint // number of elements
cap uint // allocated number of elements
}
type gobuf struct {
// The offsets of sp, pc, and g are known to (hard-coded in) libmach.
sp uintptr
pc uintptr
g *g
ctxt unsafe.Pointer // this has to be a pointer so that gc scans it
ret uintreg
lr uintptr
}
// Known to compiler.
// Changes here must also be made in src/cmd/gc/select.c's selecttype.
type sudog struct {
g *g
selectdone *uint32
next *sudog
prev *sudog
elem unsafe.Pointer // data element
releasetime int64
nrelease int32 // -1 for acquire
waitlink *sudog // g.waiting list
}
type gcstats struct {
// the struct must consist of only uint64's,
// because it is casted to uint64[].
nhandoff uint64
nhandoffcnt uint64
nprocyield uint64
nosyield uint64
nsleep uint64
}
type libcall struct {
fn uintptr
n uintptr // number of parameters
args uintptr // parameters
r1 uintptr // return values
r2 uintptr
err uintptr // error number
}
// describes how to handle callback
type wincallbackcontext struct {
gobody unsafe.Pointer // go function to call
argsize uintptr // callback arguments size (in bytes)
restorestack uintptr // adjust stack on return by (in bytes) (386 only)
cleanstack bool
}
// Stack describes a Go execution stack.
// The bounds of the stack are exactly [lo, hi),
// with no implicit data structures on either side.
type stack struct {
lo uintptr
hi uintptr
}
type g struct {
// Stack parameters.
// stack describes the actual stack memory: [stack.lo, stack.hi).
// stackguard0 is the stack pointer compared in the Go stack growth prologue.
// It is stack.lo+StackGuard normally, but can be StackPreempt to trigger a preemption.
// stackguard1 is the stack pointer compared in the C stack growth prologue.
// It is stack.lo+StackGuard on g0 and gsignal stacks.
// It is ~0 on other goroutine stacks, to trigger a call to morestackc (and crash).
stack stack // offset known to runtime/cgo
stackguard0 uintptr // offset known to liblink
stackguard1 uintptr // offset known to liblink
_panic *_panic // innermost panic - offset known to liblink
_defer *_defer // innermost defer
sched gobuf
syscallsp uintptr // if status==gsyscall, syscallsp = sched.sp to use during gc
syscallpc uintptr // if status==gsyscall, syscallpc = sched.pc to use during gc
param unsafe.Pointer // passed parameter on wakeup
atomicstatus uint32
goid int64
waitsince int64 // approx time when the g become blocked
waitreason string // if status==gwaiting
schedlink *g
issystem bool // do not output in stack dump, ignore in deadlock detector
preempt bool // preemption signal, duplicates stackguard0 = stackpreempt
paniconfault bool // panic (instead of crash) on unexpected fault address
preemptscan bool // preempted g does scan for gc
gcworkdone bool // debug: cleared at begining of gc work phase cycle, set by gcphasework, tested at end of cycle
throwsplit bool // must not split stack
raceignore int8 // ignore race detection events
m *m // for debuggers, but offset not hard-coded
lockedm *m
sig uint32
writebuf []byte
sigcode0 uintptr
sigcode1 uintptr
sigpc uintptr
gopc uintptr // pc of go statement that created this goroutine
racectx uintptr
waiting *sudog // sudog structures this g is waiting on (that have a valid elem ptr)
end [0]byte
}
type mts struct {
tv_sec int64
tv_nsec int64
}
type mscratch struct {
v [6]uintptr
}
type m struct {
g0 *g // goroutine with scheduling stack
morebuf gobuf // gobuf arg to morestack
// Fields not known to debuggers.
procid uint64 // for debuggers, but offset not hard-coded
gsignal *g // signal-handling g
tls [4]uintptr // thread-local storage (for x86 extern register)
mstartfn unsafe.Pointer // todo go func()
curg *g // current running goroutine
caughtsig *g // goroutine running during fatal signal
p *p // attached p for executing go code (nil if not executing go code)
nextp *p
id int32
mallocing int32
throwing int32
gcing int32
locks int32
softfloat int32
dying int32
profilehz int32
helpgc int32
spinning bool // m is out of work and is actively looking for work
blocked bool // m is blocked on a note
inwb bool // m is executing a write barrier
printlock int8
fastrand uint32
ncgocall uint64 // number of cgo calls in total
ncgo int32 // number of cgo calls currently in progress
cgomal *cgomal
park note
alllink *m // on allm
schedlink *m
machport uint32 // return address for mach ipc (os x)
mcache *mcache
lockedg *g
createstack [32]uintptr // stack that created this thread.
freglo [16]uint32 // d[i] lsb and f[i]
freghi [16]uint32 // d[i] msb and f[i+16]
fflag uint32 // floating point compare flags
locked uint32 // tracking for lockosthread
nextwaitm *m // next m waiting for lock
waitsema uintptr // semaphore for parking on locks
waitsemacount uint32
waitsemalock uint32
gcstats gcstats
needextram bool
traceback uint8
waitunlockf unsafe.Pointer // todo go func(*g, unsafe.pointer) bool
waitlock unsafe.Pointer
//#ifdef GOOS_windows
thread uintptr // thread handle
// these are here because they are too large to be on the stack
// of low-level NOSPLIT functions.
libcall libcall
libcallpc uintptr // for cpu profiler
libcallsp uintptr
libcallg *g
//#endif
//#ifdef GOOS_solaris
perrno *int32 // pointer to tls errno
// these are here because they are too large to be on the stack
// of low-level NOSPLIT functions.
//LibCall libcall;
ts mts
scratch mscratch
//#endif
//#ifdef GOOS_plan9
notesig *int8
errstr *byte
//#endif
end [0]byte
}
type p struct {
lock mutex
id int32
status uint32 // one of pidle/prunning/...
link *p
schedtick uint32 // incremented on every scheduler call
syscalltick uint32 // incremented on every system call
m *m // back-link to associated m (nil if idle)
mcache *mcache
deferpool [5]*_defer // pool of available defer structs of different sizes (see panic.c)
// Cache of goroutine ids, amortizes accesses to runtime·sched.goidgen.
goidcache uint64
goidcacheend uint64
// Queue of runnable goroutines.
runqhead uint32
runqtail uint32
runq [256]*g
// Available G's (status == Gdead)
gfree *g
gfreecnt int32
pad [64]byte
}
const (
// The max value of GOMAXPROCS.
// There are no fundamental restrictions on the value.
_MaxGomaxprocs = 1 << 8
)
type schedt struct {
lock mutex
goidgen uint64
midle *m // idle m's waiting for work
nmidle int32 // number of idle m's waiting for work
nmidlelocked int32 // number of locked m's waiting for work
mcount int32 // number of m's that have been created
maxmcount int32 // maximum number of m's allowed (or die)
pidle *p // idle p's
npidle uint32
nmspinning uint32
// Global runnable queue.
runqhead *g
runqtail *g
runqsize int32
// Global cache of dead G's.
gflock mutex
gfree *g
ngfree int32
gcwaiting uint32 // gc is waiting to run
stopwait int32
stopnote note
sysmonwait uint32
sysmonnote note
lastpoll uint64
profilehz int32 // cpu profiling rate
}
// The m->locked word holds two pieces of state counting active calls to LockOSThread/lockOSThread.
// The low bit (LockExternal) is a boolean reporting whether any LockOSThread call is active.
// External locks are not recursive; a second lock is silently ignored.
// The upper bits of m->lockedcount record the nesting depth of calls to lockOSThread
// (counting up by LockInternal), popped by unlockOSThread (counting down by LockInternal).
// Internal locks can be recursive. For instance, a lock for cgo can occur while the main
// goroutine is holding the lock during the initialization phase.
const (
_LockExternal = 1
_LockInternal = 2
)
type sigtabtt struct {
flags int32
name *int8
}
const (
_SigNotify = 1 << 0 // let signal.Notify have signal, even if from kernel
_SigKill = 1 << 1 // if signal.Notify doesn't take it, exit quietly
_SigThrow = 1 << 2 // if signal.Notify doesn't take it, exit loudly
_SigPanic = 1 << 3 // if the signal is from the kernel, panic
_SigDefault = 1 << 4 // if the signal isn't explicitly requested, don't monitor it
_SigHandling = 1 << 5 // our signal handler is registered
_SigIgnored = 1 << 6 // the signal was ignored before we registered for it
_SigGoExit = 1 << 7 // cause all runtime procs to exit (only used on Plan 9).
)
// Layout of in-memory per-function information prepared by linker
// See http://golang.org/s/go12symtab.
// Keep in sync with linker and with ../../libmach/sym.c
// and with package debug/gosym and with symtab.go in package runtime.
type _func struct {
entry uintptr // start pc
nameoff int32 // function name
args int32 // in/out args size
frame int32 // legacy frame size; use pcsp if possible
pcsp int32
pcfile int32
pcln int32
npcdata int32
nfuncdata int32
}
// layout of Itab known to compilers
// allocated in non-garbage-collected memory
type itab struct {
inter *interfacetype
_type *_type
link *itab
bad int32
unused int32
fun [0]uintptr
}
const (
// TODO: Generate in cmd/dist.
_NaCl = 0
_Windows = 0
_Solaris = 0
_Plan9 = 0
)
// Lock-free stack node.
// // Also known to export_test.go.
type lfnode struct {
next uint64
pushcnt uintptr
}
// Parallel for descriptor.
type parfor struct {
body unsafe.Pointer // go func(*parfor, uint32), executed for each element
done uint32 // number of idle threads
nthr uint32 // total number of threads
nthrmax uint32 // maximum number of threads
thrseq uint32 // thread id sequencer
cnt uint32 // iteration space [0, cnt)
ctx unsafe.Pointer // arbitrary user context
wait bool // if true, wait while all threads finish processing,
// otherwise parfor may return while other threads are still working
thr *parforthread // array of thread descriptors
pad uint32 // to align parforthread.pos for 64-bit atomic operations
// stats
nsteal uint64
nstealcnt uint64
nprocyield uint64
nosyield uint64
nsleep uint64
}
// Track memory allocated by code not written in Go during a cgo call,
// so that the garbage collector can see them.
type cgomal struct {
next *cgomal
alloc unsafe.Pointer
}
// Holds variables parsed from GODEBUG env var.
type debugvars struct {
allocfreetrace int32
efence int32
gctrace int32
gcdead int32
scheddetail int32
schedtrace int32
scavenge int32
}
// Indicates to write barrier and sychronization task to preform.
const (
_GCoff = iota // GC not running, write barrier disabled
_GCquiesce // unused state
_GCstw // unused state
_GCscan // GC collecting roots into workbufs, write barrier disabled
_GCmark // GC marking from workbufs, write barrier ENABLED
_GCmarktermination // GC mark termination: allocate black, P's help GC, write barrier ENABLED
_GCsweep // GC mark completed; sweeping in background, write barrier disabled
)
type forcegcstate struct {
lock mutex
g *g
idle uint32
}
var gcphase uint32
/*
* known to compiler
*/
const (
_Structrnd = regSize
)
var startup_random_data *byte
var startup_random_data_len uint32
var invalidptr int32
const (
// hashinit wants this many random bytes
_HashRandomBytes = 32
)
/*
* deferred subroutine calls
*/
type _defer struct {
siz int32
started bool
argp uintptr // where args were copied from
pc uintptr
fn *funcval
_panic *_panic // panic that is running defer
link *_defer
}
/*
* panics
*/
type _panic struct {
argp unsafe.Pointer // pointer to arguments of deferred call run during panic; cannot move - known to liblink
arg interface{} // argument to panic
link *_panic // link to earlier panic
recovered bool // whether this panic is over
aborted bool // the panic was aborted
}
/*
* stack traces
*/
type stkframe struct {
fn *_func // function being run
pc uintptr // program counter within fn
continpc uintptr // program counter where execution can continue, or 0 if not
lr uintptr // program counter at caller aka link register
sp uintptr // stack pointer at pc
fp uintptr // stack pointer at caller aka frame pointer
varp uintptr // top of local variables
argp uintptr // pointer to function arguments
arglen uintptr // number of bytes at argp
argmap *bitvector // force use of this argmap
}
const (
_TraceRuntimeFrames = 1 << 0 // include frames for internal runtime functions.
_TraceTrap = 1 << 1 // the initial PC, SP are from a trap, not a return PC from a call
)
const (
// The maximum number of frames we print for a traceback
_TracebackMaxFrames = 100
)
var (
emptystring string
allg **g
allglen uintptr
lastg *g
allm *m
allp [_MaxGomaxprocs + 1]*p
gomaxprocs int32
needextram uint32
panicking uint32
goos *int8
ncpu int32
iscgo bool
cpuid_ecx uint32
cpuid_edx uint32
debug debugvars
signote note
forcegc forcegcstate
sched schedt
newprocs int32
)
/*
* mutual exclusion locks. in the uncontended case,
* as fast as spin locks (just a few user-level instructions),
* but on the contention path they sleep in the kernel.
* a zeroed Mutex is unlocked (no need to initialize each lock).
*/
/*
* sleep and wakeup on one-time events.
* before any calls to notesleep or notewakeup,
* must call noteclear to initialize the Note.
* then, exactly one thread can call notesleep
* and exactly one thread can call notewakeup (once).
* once notewakeup has been called, the notesleep
* will return. future notesleep will return immediately.
* subsequent noteclear must be called only after
* previous notesleep has returned, e.g. it's disallowed
* to call noteclear straight after notewakeup.
*
* notetsleep is like notesleep but wakes up after
* a given number of nanoseconds even if the event
* has not yet happened. if a goroutine uses notetsleep to
* wake up early, it must wait to call noteclear until it
* can be sure that no other goroutine is calling
* notewakeup.
*
* notesleep/notetsleep are generally called on g0,
* notetsleepg is similar to notetsleep but is called on user g.
*/
// bool runtime·notetsleep(Note*, int64); // false - timeout
// bool runtime·notetsleepg(Note*, int64); // false - timeout
/*
* Lock-free stack.
* Initialize uint64 head to 0, compare with 0 to test for emptiness.
* The stack does not keep pointers to nodes,
* so they can be garbage collected if there are no other pointers to nodes.
*/
/*
* Parallel for over [0, n).
* body() is executed for each iteration.
* nthr - total number of worker threads.
* ctx - arbitrary user context.
* if wait=true, threads return from parfor() when all work is done;
* otherwise, threads can return while other threads are still finishing processing.
*/
// for mmap, we only pass the lower 32 bits of file offset to the
// assembly routine; the higher bits (if required), should be provided
// by the assembly routine as 0.