The pid field in the Tos structure is a 32-bit value.
Loading a 64-bit word also brings in the next field
which is used for the profiling clock.
LGTM=0intro, aram
R=rsc, 0intro, aram
CC=golang-codereviews, mischief
https://golang.org/cl/139560044
The goal here is to allow assembly functions to appear in the middle
of a Go stack (having called other code) and still record enough information
about their pointers so that stack copying and garbage collection can handle
them precisely. Today, these frames are handled only conservatively.
If you write
func myfunc(x *float64) (y *int)
(with no body, an 'extern' declaration), then the Go compiler now emits
a liveness bitmap for use from the assembly definition of myfunc.
The bitmap symbol is myfunc.args_stackmap and it contains two bitmaps.
The first bitmap, in effect at function entry, marks all inputs as live.
The second bitmap, not in effect at function entry, marks the outputs
live as well.
In funcdata.h, define new assembly macros:
GO_ARGS opts in to using the Go compiler-generated liveness bitmap
for the current function.
GO_RESULTS_INITIALIZED indicates that the results have been initialized
and need to be kept live for the remainder of the function; it causes a
switch to the second generated bitmap for the assembly code that follows.
NO_LOCAL_POINTERS indicates that there are no pointers in the
local variables being stored in the function's stack frame.
LGTM=khr
R=khr
CC=golang-codereviews
https://golang.org/cl/137520043
Tests will come in a separate CL after the funcdata stuff is resolved.
Update #8696
LGTM=iant, rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/138330045
Just go ahead and do it, if something is wrong we'll throw.
Also rip out cc-generated arg ptr maps, they are useless now.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/133690045
Replacing gosched with Gosched broke some builds because
some of the call sites are at times when the stack cannot be grown.
TBR=khr
CC=golang-codereviews
https://golang.org/cl/142000043
A write *p = x that needs a write barrier (not all do)
now turns into runtime.writebarrierptr(p, x)
or one of the other variants.
The write barrier implementations are trivial.
The goal here is to emit the calls in the correct places
and to incur the cost of those function calls in the Go 1.4 cycle.
Performance on the Go 1 benchmark suite below.
Remember, the goal is to slow things down (and be correct).
We will look into optimizations in separate CLs, as part of
the process of comparing Go 1.3 against tip in order to make
sure Go 1.4 runs at least as fast as Go 1.3.
benchmark old ns/op new ns/op delta
BenchmarkBinaryTree17 3118336716 3452876110 +10.73%
BenchmarkFannkuch11 3184497677 3211552284 +0.85%
BenchmarkFmtFprintfEmpty 89.9 107 +19.02%
BenchmarkFmtFprintfString 236 287 +21.61%
BenchmarkFmtFprintfInt 246 278 +13.01%
BenchmarkFmtFprintfIntInt 395 458 +15.95%
BenchmarkFmtFprintfPrefixedInt 343 378 +10.20%
BenchmarkFmtFprintfFloat 477 525 +10.06%
BenchmarkFmtManyArgs 1446 1707 +18.05%
BenchmarkGobDecode 14398047 14685958 +2.00%
BenchmarkGobEncode 12557718 12947104 +3.10%
BenchmarkGzip 453462345 472413285 +4.18%
BenchmarkGunzip 114226016 115127398 +0.79%
BenchmarkHTTPClientServer 114689 112122 -2.24%
BenchmarkJSONEncode 24914536 26135942 +4.90%
BenchmarkJSONDecode 86832877 103620289 +19.33%
BenchmarkMandelbrot200 4833452 4898780 +1.35%
BenchmarkGoParse 4317976 4835474 +11.98%
BenchmarkRegexpMatchEasy0_32 150 166 +10.67%
BenchmarkRegexpMatchEasy0_1K 393 402 +2.29%
BenchmarkRegexpMatchEasy1_32 125 142 +13.60%
BenchmarkRegexpMatchEasy1_1K 1010 1236 +22.38%
BenchmarkRegexpMatchMedium_32 232 301 +29.74%
BenchmarkRegexpMatchMedium_1K 76963 102721 +33.47%
BenchmarkRegexpMatchHard_32 3833 5463 +42.53%
BenchmarkRegexpMatchHard_1K 119668 161614 +35.05%
BenchmarkRevcomp 763449047 706768534 -7.42%
BenchmarkTemplate 124954724 134834549 +7.91%
BenchmarkTimeParse 517 511 -1.16%
BenchmarkTimeFormat 501 514 +2.59%
benchmark old MB/s new MB/s speedup
BenchmarkGobDecode 53.31 52.26 0.98x
BenchmarkGobEncode 61.12 59.28 0.97x
BenchmarkGzip 42.79 41.08 0.96x
BenchmarkGunzip 169.88 168.55 0.99x
BenchmarkJSONEncode 77.89 74.25 0.95x
BenchmarkJSONDecode 22.35 18.73 0.84x
BenchmarkGoParse 13.41 11.98 0.89x
BenchmarkRegexpMatchEasy0_32 213.30 191.72 0.90x
BenchmarkRegexpMatchEasy0_1K 2603.92 2542.74 0.98x
BenchmarkRegexpMatchEasy1_32 254.00 224.93 0.89x
BenchmarkRegexpMatchEasy1_1K 1013.53 827.98 0.82x
BenchmarkRegexpMatchMedium_32 4.30 3.31 0.77x
BenchmarkRegexpMatchMedium_1K 13.30 9.97 0.75x
BenchmarkRegexpMatchHard_32 8.35 5.86 0.70x
BenchmarkRegexpMatchHard_1K 8.56 6.34 0.74x
BenchmarkRevcomp 332.92 359.62 1.08x
BenchmarkTemplate 15.53 14.39 0.93x
LGTM=rlh
R=rlh
CC=dvyukov, golang-codereviews, iant, khr, r
https://golang.org/cl/136380043
The uses of onM in dopanic/startpanic are okay even from the signal stack.
Fixes#8666.
LGTM=khr
R=khr
CC=golang-codereviews
https://golang.org/cl/134710043
They will both need write barriers at some point.
But until then, no reason why we shouldn't share.
LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews
https://golang.org/cl/141330043
The previous implementation had several subtle issues. It's not
clear if any of these could actually be causing the flakiness
problems on openbsd/386, but fixing them should only help.
1. thrsleep() is implemented internally as unlock, then test *abort
(if abort != nil), then tsleep(). Under the current code, that makes
it theoretically possible that semasleep()/thrsleep() could release
waitsemalock, then a racing semawakeup() could acquire the lock,
increment waitsemacount, and call thrwakeup()/wakeup() before
thrsleep() reaches tsleep(). (In practice, OpenBSD's big kernel lock
seems unlikely to let this actually happen.)
The proper way to avoid this is to pass &waitsemacount as the abort
pointer to thrsleep so thrsleep knows to re-check it before going to
sleep, and to wakeup if it's non-zero. Then we avoid any races.
(I actually suspect openbsd's sema{sleep,wakeup}() could be further
simplified using cas/xadd instead of locks, but I don't want to be
more intrusive than necessary so late in the 1.4 release cycle.)
2. semasleep() takes a relative sleep duration, but thrsleep() needs
an absolute sleep deadline. Instead of recomputing the deadline each
iteration, compute it once up front and use (*Timespec)(nil) to signify
no deadline. Ensures we retry properly if there's a spurious wakeup.
3. Instead of assuming if thrsleep() woke up and waitsemacount wasn't
available that we must have hit the deadline, check that the system
call returned EWOULDBLOCK.
4. Instead of assuming that 64-bit systems are little-endian, compute
timediv() using a temporary int32 nsec and then assign it to tv_nsec.
LGTM=iant
R=jsing, iant
CC=golang-codereviews
https://golang.org/cl/137960043
A race exists between the parent and child processes after a fork.
The child needs to access the new M pointer passed as an argument
but the parent may have already returned and clobbered it.
Previously, we avoided this by saving the necessary data into
registers before the rfork system call but this isn't guaranteed
to work because Plan 9 makes no promises about the register state
after a system call. Only the 386 kernel seems to save them.
For amd64 and arm, this method won't work.
We eliminate the race by allocating stack space for the scheduler
goroutines (g0) in the per-process copy-on-write stack segment and
by only calling rfork on the scheduler stack.
LGTM=aram, 0intro, rsc
R=aram, 0intro, mischief, rsc
CC=golang-codereviews
https://golang.org/cl/110680044
The only thing I can see that is really Plan 9-specific
is that the stack pointer used for signal handling used
to have more mapped memory above it.
Specifically it used to have at most 88 bytes (StackTop),
so change the allocation of a 40-byte frame to a 128-byte frame.
No idea if this will work, but worth a try.
Note that "fix" here means get it back to timing out
instead of crashing.
TBR=iant
CC=golang-codereviews
https://golang.org/cl/142840043
The difference between the old and the new (from earlier) code
is that we set stackguard = stack.lo + StackGuard, while the old
code set stackguard = stack.lo. That 512 bytes appears to be
the difference between the profileloop function running and not running.
We don't know how big the system stack is, but it is likely MUCH bigger than 4k.
Give Go/C 8k.
TBR=iant
CC=golang-codereviews
https://golang.org/cl/140440044
Start the stack a few words below the actual top, so that
if something tries to read goexit's caller PC from the stack,
it won't fault on a bad memory address.
Today, heapdump does that.
Maybe tomorrow, traceback or something else will do that.
Make it not a bug.
TBR=khr
R=khr
CC=golang-codereviews
https://golang.org/cl/136450043
Commit to stack copying for stack growth.
We're carrying around a surprising amount of cruft from older schemes.
I am confident that precise stack scans and stack copying are here to stay.
Delete fallback code for when precise stack info is disabled.
Delete fallback code for when copying stacks is disabled.
Delete fallback code for when StackCopyAlways is disabled.
Delete Stktop chain - there is only one stack segment now.
Delete M.moreargp, M.moreargsize, M.moreframesize, M.cret.
Delete G.writenbuf (unrelated, just dead).
Delete runtime.lessstack, runtime.oldstack.
Delete many amd64 morestack variants.
Delete initialization of morestack frame/arg sizes (shortens split prologue!).
Replace G's stackguard/stackbase/stack0/stacksize/
syscallstack/syscallguard/forkstackguard with simple stack
bounds (lo, hi).
Update liblink, runtime/cgo for adjustments to G.
LGTM=khr
R=khr, bradfitz
CC=golang-codereviews, iant, r
https://golang.org/cl/137410043
I have found better approach, then longer wait.
See CL 134360043 for details.
««« original CL description
runtime/pprof: adjust cpuHogger so that tests pass on windows builders
LGTM=rsc
R=dvyukov, rsc
CC=golang-codereviews
https://golang.org/cl/140110043
»»»
LGTM=dave
R=golang-codereviews, dave, dvyukov
CC=golang-codereviews
https://golang.org/cl/133500043
I assumed they were the same when I wrote
cgocallback.go earlier today. Merge them
to eliminate confusion.
I can't tell what gomallocgc did before with
a nil type but without FlagNoScan.
I created a call like that in cgocallback.go
this morning, translating from a C file.
It was supposed to do what the C version did,
namely treat the block conservatively.
Now it will.
LGTM=khr
R=khr
CC=golang-codereviews
https://golang.org/cl/141810043
It already is updating parts of them; we're just getting lucky
retraversing them and not finding much to do.
Change argp to a pointer so that it will be updated too.
Existing tests break if you apply the change to adjustpanics
without also updating the type of argp.
LGTM=khr
R=khr
CC=golang-codereviews
https://golang.org/cl/139380043
It worked at CL 134660043 on the builders,
so I believe it will stick this time.
LGTM=bradfitz
R=khr, bradfitz
CC=golang-codereviews
https://golang.org/cl/141280043
This should make deferreturn nosplit all the way down,
which should fix the current windows/amd64 failure.
If not, I will change StackCopyAlways back to 0.
TBR=khr
CC=golang-codereviews
https://golang.org/cl/135600043
Let's see how close we are to this being ready.
Will roll back if it breaks any builds in non-trivial ways.
LGTM=r, khr
R=iant, khr, r
CC=golang-codereviews
https://golang.org/cl/138200043
The sighander has been run at the bottom of the
currently executing goroutine stack, but it's in C,
and we don't want C on our ordinary goroutine stacks.
Worse, it does a lot of stuff, and it might need more
stack space. There is scary code in traceback_windows.go
that talks about stack splits during sighandler.
Moving sighandler to g0 will eliminate the possibility
of stack splits and such, and then we can delete
traceback_windows.go entirely. Win win.
On the builder, all.bat passes with GOARCH=amd64
and all.bat gets most of the way with GOARCH=386
except for a DLL-loading test that I think is unrelated.
Fixes windows build.
TBR=brainman, iant
CC=golang-codereviews
https://golang.org/cl/140380043
This CL contains compiler+runtime changes that detect C code
running on Go (not g0, not gsignal) stacks, and it contains
corrections for what it detected.
The detection works by changing the C prologue to use a different
stack guard word in the G than Go prologue does. On the g0 and
gsignal stacks, that stack guard word is set to the usual
stack guard value. But on ordinary Go stacks, that stack
guard word is set to ^0, which will make any stack split
check fail. The C prologue then calls morestackc instead
of morestack, and morestackc aborts the program with
a message about running C code on a Go stack.
This check catches all C code running on the Go stack
except NOSPLIT code. The NOSPLIT code is allowed,
so the check is complete. Since it is a dynamic check,
the code must execute to be caught. But unlike the static
checks we've been using in cmd/ld, the dynamic check
works with function pointers and other indirect calls.
For example it caught sigpanic being pushed onto Go
stacks in the signal handlers.
Fixes#8667.
LGTM=khr, iant
R=golang-codereviews, khr, iant
CC=golang-codereviews, r
https://golang.org/cl/133700043
avoid tight coupling between deferreturn and jmpdefer.
before, jmpdefer knew the exact frame size of deferreturn
in order to pop it off the stack. now, deferreturn passes
jmpdefer a pointer to the frame above it explicitly.
that avoids a magic constant and should be less fragile.
R=r
DELTA=32 (6 added, 3 deleted, 23 changed)
OCL=29801
CL=29804
The code was already careful not to use malloc/free
for stack growth during calls to malloc.
Avoid them during calls to free too.
R=r
DELTA=9 (7 added, 0 deleted, 2 changed)
OCL=29606
CL=29610
* string format changed
* files got renamed
* new files that i forgot to check in last time
updates are all copy and paste from 6g
R=ken
OCL=29385
CL=29400
this is not a user-visible change.
before, all interface values were
struct Itype {
Sigt *type;
Sigi *inter;
void *method[n];
}
struct Iface {
void *addr;
Itype *itype;
}
the itype is basically a vtable, but it's unnecessary
if the static type is interface{ }.
for interface values with static type empty, the
new representation is
struct Eface {
void *addr;
Sigt *type;
}
this complicates the code somewhat, but
it reduces the number of Itypes that
have to be computed and cached,
it opens up opportunities to avoid function
calls in a few common cases,
and it will make it possible to lay out
interface{} values at compile time,
which i think i'll need for the new reflection.
R=ken
OCL=28701
CL=29121
* byteastring is no longer used
* do not generate ODCL, OAS for globals
(wasn't generating any code but might
save one or two init functions)
* do not call self from Init function
R=ken
OCL=28309
CL=28309
Currently a http server will be killed on receipt of SIGPIPE
if a client closes a socket which the server is trying to
write to.
R=rsc
APPROVED=rsc
DELTA=2 (0 added, 0 deleted, 2 changed)
OCL=27959
CL=28055
add test for string range.
test has minor failure: after loop the index == len(s); should be len(s)-1
in this case. according to spec, vars are left at position at last
iteration.
R=ken,rsc
DELTA=259 (161 added, 96 deleted, 2 changed)
OCL=27343
CL=27343
160 - 75 was just barely not enough for deferproc + morestack.
added enum names and bumped to 256 - 128.
added explanation.
changed a few mal() (garbage-collected) to
malloc()/free() (manually collected).
R=ken
OCL=26981
CL=26981
remove use of _subv in vlrt.c
darwin/386/signal.c
darwin/386/*
linux/386/* (forgotten before)
can run empty program on darwin/386 now.
R=r
DELTA=1140 (1021 added, 114 deleted, 5 changed)
OCL=26942
CL=26968
move darwin-amd64 specific code into runtime/darwin/amd64/
repeat for linux.
move rt0 into runtime.a instead of keeping a separate .6 file.
6l seems to have no problem with that.
TBR=r
OCL=26680
CL=26680
trying to find all the places where
spans might be recorded.
Free can cascade into complicated
span manipulations that move them
from list to list; the old code had the
possibility of accidentally processing
a span twice or jumping to a different
list, causing an infinite loop.
R=r
DELTA=70 (28 added, 25 deleted, 17 changed)
OCL=23704
CL=23710
though they still build in src/runtime.
use cgo instead of hand-written wrappers.
R=r
DELTA=740 (289 added, 300 deleted, 151 changed)
OCL=23326
CL=23331
implement hiding lowercase methods m in
signatures by adding in a hash of the package name
to the type hash code.
remove remaining checks for internally-generated _ names:
they are all gone.
R=ken
OCL=23236
CL=23238
lets us use a single source file for both 6c and gcc, handling
the incompatible handling of return values.
R=rsc
DELTA=649 (613 added, 35 deleted, 1 changed)
OCL=22682
CL=22730
+ Use macros to name symbols with non-ASCII characters.
+ Make some variables unsigned, because they are compared
against unsigned values.
+ Fix a few void* pointers to be MLink*.
R=rsc
DELTA=94 (44 added, 3 deleted, 47 changed)
OCL=22303
CL=22638
mark and sweep, stop the world garbage collector
(intermediate step in the way to ref counting).
can run pretty with an explicit gc after each file.
R=r
DELTA=502 (346 added, 143 deleted, 13 changed)
OCL=20630
CL=20635
run oldstack on g0's stack, just like newstack does,
so that oldstack can free the old stack.
R=r
DELTA=53 (44 added, 0 deleted, 9 changed)
OCL=20404
CL=20433
not number of threads. can still starve all the other threads,
but only by looping, not by waiting in a system call.
fix darwin syscall.Syscall6 bug.
fix chanclient bug.
delete $GOMAXPROCS from network tests.
add stripped down printf, sys.printhex to runtime.
R=r
DELTA=355 (217 added, 36 deleted, 102 changed)
OCL=20017
CL=20019
in favor of using in-memory copy of symbol table.
$ ls -l pretty pretty.big
-rwxr-xr-x 1 rsc eng 439516 Nov 21 16:43 pretty
-rwxr-xr-x 1 rsc eng 580984 Nov 21 16:20 pretty.big
$
R=r
DELTA=446 (238 added, 178 deleted, 30 changed)
OCL=19851
CL=19884
* add gotype string to symbol table
* fill in gotype in 6l for known funcs/vars
* print gotype with nm -t
* load symbol and pc/ln tables into memory at magic address 0x99<<32.
* add sys.symdat() to retrieve raw bytes of symbol table
and pc/ln table.
most of this should be considered experimental
and subject to change.
R=r
DELTA=157 (128 added, 0 deleted, 29 changed)
OCL=19746
CL=19750
* use union, not cast, to convert between uint64 and float64,
to avoid possible problems with gcc in future.
R=r
DELTA=75 (39 added, 15 deleted, 21 changed)
OCL=18926
CL=18926
package main
func main() {
var i interface { } = 1;
a := i.(*[]byte);
}
interface { } is int, not *[]uint8
throw: interface conversion
package main
func main() {
var i interface { };
a := i.(*[]byte);
}
interface is nil, not *[]uint8
throw: interface conversion
package main
func main() {
i := sys.unreflect(0, "*bogus");
a := i.(*[]byte);
}
interface { } is *bogus, not *[]uint8
throw: interface conversion
R=r
DELTA=30 (24 added, 2 deleted, 4 changed)
OCL=18548
CL=18565
* allow conversion between nil interface and any type.
* mark signatures as DUPOK so that multiple .6 can
contain sigt.*[]byte and only one gets used.
R=ken
OCL=18538
CL=18542
sigi and sigt:
sys·sigi_inter -> sigi·inter
sys·sigt_int -> sigt·int
Package·sigt_Type -> sigt·Package.Type
local type T in file x.go T_x -> T·x
second one T_x_1 -> T·x·1
method names M on T T_M -> T·M
correctly handle local embedded types
init functions are the only place left that use underscores
R=ken
OCL=18377
CL=18377
- pointer to interface cannot have methods
- record type names for better runtime error
R=r,ken
DELTA=85 (80 added, 0 deleted, 5 changed)
OCL=16658
CL=16722
to string convert. if the byte array has length 0,
the computation of &a[0] throws an index bounds error.
for fixed size arrays, this ends up invoking arrays2d
unnecessarily, but it works.
R=ken
DELTA=304 (44 added, 28 deleted, 232 changed)
OCL=15674
CL=15678
- do not print tracebacks if $GOTRACEBACK=0
- set GOTRACEBACK=0 during tests
- filter out pc numbers in errors
R=r
DELTA=70 (22 added, 30 deleted, 18 changed)
OCL=15618
CL=15642
*** Reason for rollback ***
<enter reason for rollback>
*** Original change description ***
correct signal name thru package rename
R=r
OCL=15313
CL=15313
- disassemble the instructions in a trace trap to see if it's a run-time trap
- if so, print relevant info
- avoid double-printing traceback on panic
R=ken,rsc
DELTA=66 (50 added, 7 deleted, 9 changed)
OCL=15199
CL=15224
* rewrite lock implementation to be correct
(tip: never assume that an algorithm you found
in a linux man page is correct.)
* delete unneeded void* arg from clone fn
* replace Rendez with Note
* comment mal better
* use 6c -w, fix warnings
* mark all assembly functions 7
R=r
DELTA=828 (338 added, 221 deleted, 269 changed)
OCL=13884
CL=13886
* kick off new os procs (machs) as needed
* add sys·sleep for testing
* add Lock, Rendez
* properly lock mal, sys·newproc, scheduler
* linux syscall arg #4 is in R10, not CX
* chans are not multithread-safe yet
* multithreading disabled by default;
set $gomaxprocs=2 (or 1000) to turn it on
This should build on OS X but may not.
Rob and I will fix soon after submitting.
TBR=r
OCL=13784
CL=13842
