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Commit Graph

701 Commits

Author SHA1 Message Date
Austin Clements
006ceb2f1d runtime: fix missing newline when dumping bad symbol table
If the symbol table isn't sorted, we print it and abort.  However, we
were missing the line break after each symbol, resulting in one
gigantic line instead of a nicely formatted table.

Change-Id: Ie5c6f3c256d0e648277cb3db4496512a79d266dd
Reviewed-on: https://go-review.googlesource.com/1182
Reviewed-by: Russ Cox <rsc@golang.org>
2014-12-08 18:39:58 +00:00
Russ Cox
31457cef6d all: merge dev.garbage (d1238958d4ae) into default branch
When we start work on Gerrit, ppc64 and garbage collection
work will continue in the master branch, not the dev branches.

(We may still use dev branches for other things later, but
these are ready to be merged, and doing it now, before moving
to Git means we don't have to have dev branches working
in the Gerrit workflow on day one.)

TBR=rlh
CC=golang-codereviews
https://golang.org/cl/183140043
2014-12-05 20:34:45 -05:00
Russ Cox
db40624110 [dev.garbage] runtime: raise StackGuard limit for Windows (again)
640 bytes ought to be enough for anybody.

We'll bring this back down before Go 1.5. That's issue 9214.

TBR=rlh
CC=golang-codereviews
https://golang.org/cl/188730043
2014-12-05 19:50:09 -05:00
Russ Cox
09d92b6bbf all: power64 is now ppc64
Fixes #8654.

LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/180600043
2014-12-05 19:13:20 -05:00
Russ Cox
fa6c54953c [dev.garbage] runtime: reduce stack footprint of write barriers
This is going to hurt a bit but we'll make it better later.
Now the race detector can be run again.

I added the write barrier optimizations from
CL 183020043 to try to make it hurt a little less.

TBR=rlh
CC=golang-codereviews
https://golang.org/cl/185070043
2014-12-05 16:47:50 -05:00
Russ Cox
dcb2ec3b65 runtime: generate windows callback list with go generate
This is the last system-dependent file written by cmd/dist.
They are all now written by go generate.

cmd/dist is not needed to start building package runtime
for a different system anymore.

Now all the generated files can be assumed generated, so
delete the clumsy hacks in cmd/api.

Re-enable api check in run.bash.

LGTM=bradfitz
R=bradfitz
CC=golang-codereviews
https://golang.org/cl/185040044
2014-12-05 16:24:20 -05:00
Russ Cox
7d516079de runtime: convert netbsd/arm to Go
This was the last src/runtime/*.c file.

LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/187770043
2014-12-05 16:17:09 -05:00
Russ Cox
444839014b [dev.garbage] all: merge dev.cc (81884b89bd88) into dev.garbage
TBR=rlh
CC=golang-codereviews
https://golang.org/cl/181100044
2014-12-05 11:40:41 -05:00
Russ Cox
829b286f2c [dev.cc] all: merge default (8d42099cdc23) into dev.cc
TBR=austin
CC=golang-codereviews
https://golang.org/cl/178700044
2014-12-05 11:18:10 -05:00
Russ Cox
2b62e1eaec runtime: fix hang in GC due to shrinkstack vs netpoll race
During garbage collection, after scanning a stack, we think about
shrinking it to reclaim some memory. The shrinking code (called
while the world is stopped) checked that the status was Gwaiting
or Grunnable and then changed the state to Gcopystack, to essentially
lock the stack so that no other GC thread is scanning it.
The same locking happens for stack growth (and is more necessary there).

        oldstatus = runtime·readgstatus(gp);
        oldstatus &= ~Gscan;
        if(oldstatus == Gwaiting || oldstatus == Grunnable)
                runtime·casgstatus(gp, oldstatus, Gcopystack); // oldstatus is Gwaiting or Grunnable
        else
                runtime·throw("copystack: bad status, not Gwaiting or Grunnable");

Unfortunately, "stop the world" doesn't stop everything. It stops all
normal goroutine execution, but the network polling thread is still
blocked in epoll and may wake up. If it does, and it chooses a goroutine
to mark runnable, and that goroutine is the one whose stack is shrinking,
then it can happen that between readgstatus and casgstatus, the status
changes from Gwaiting to Grunnable.

casgstatus assumes that if the status is not what is expected, it is a
transient change (like from Gwaiting to Gscanwaiting and back, or like
from Gwaiting to Gcopystack and back), and it loops until the status
has been restored to the expected value. In this case, the status has
changed semi-permanently from Gwaiting to Grunnable - it won't
change again until the GC is done and the world can continue, but the
GC is waiting for the status to change back. This wedges the program.

To fix, call a special variant of casgstatus that accepts either Gwaiting
or Grunnable as valid statuses.

Without the fix bug with the extra check+throw in casgstatus, the
program below dies in a few seconds (2-10) with GOMAXPROCS=8
on a 2012 Retina MacBook Pro. With the fix, it runs for minutes
and minutes.

package main

import (
        "io"
        "log"
        "net"
        "runtime"
)

func main() {
        const N = 100
        for i := 0; i < N; i++ {
                l, err := net.Listen("tcp", "127.0.0.1:0")
                if err != nil {
                        log.Fatal(err)
                }
                ch := make(chan net.Conn, 1)
                go func() {
                        var err error
                        c1, err := net.Dial("tcp", l.Addr().String())
                        if err != nil {
                                log.Fatal(err)
                        }
                        ch <- c1
                }()
                c2, err := l.Accept()
                if err != nil {
                        log.Fatal(err)
                }
                c1 := <-ch
                l.Close()
                go netguy(c1, c2)
                go netguy(c2, c1)
                c1.Write(make([]byte, 100))
        }
        for {
                runtime.GC()
        }
}

func netguy(r, w net.Conn) {
        buf := make([]byte, 100)
        for {
                bigstack(1000)
                _, err := io.ReadFull(r, buf)
                if err != nil {
                        log.Fatal(err)
                }
                w.Write(buf)
        }
}

var g int

func bigstack(n int) {
        var buf [100]byte
        if n > 0 {
                bigstack(n - 1)
        }
        g = int(buf[0]) + int(buf[99])
}

Fixes #9186.

LGTM=rlh
R=austin, rlh
CC=dvyukov, golang-codereviews, iant, khr, r
https://golang.org/cl/179680043
2014-12-01 16:32:06 -05:00
Russ Cox
b8540fc288 [dev.garbage] all: merge dev.cc (493ad916c3b1) into dev.garbage
TBR=austin
CC=golang-codereviews
https://golang.org/cl/179290043
2014-11-24 12:07:11 -05:00
Joel Sing
6ddc2cb80c [dev.cc] runtime: convert dragonfly/386 port to Go
LGTM=rsc
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/178210043
2014-11-25 03:15:11 +11:00
Joel Sing
0d76887433 [dev.cc] runtime: convert netbsd/386 port to Go
LGTM=minux
R=rsc, minux
CC=golang-codereviews
https://golang.org/cl/177170043
2014-11-22 22:09:11 +11:00
Joel Sing
cfc8099a9a [dev.cc] runtime: convert netbsd/amd64 port to Go
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/169620043
2014-11-22 16:05:31 +11:00
Shenghou Ma
d3526ea0f6 [dev.cc] runtime: migrate Android/ARM port to Go.
I tested building Go itself, but not any of go.mobile tests.

LGTM=crawshaw
R=crawshaw, rsc
CC=golang-codereviews
https://golang.org/cl/179110043
2014-11-21 18:15:30 -05:00
Shenghou Ma
adbca13cb3 [dev.cc] runtime: explicitly exclude android in zgoos_linux.go
Otherwise both zgoos_linux.go and zgoos_android.go will be compiled
for GOOS=android.

LGTM=crawshaw, rsc
R=rsc, crawshaw
CC=golang-codereviews
https://golang.org/cl/178110043
2014-11-21 18:13:59 -05:00
Rick Hudson
273507aa8f [dev.garbage] runtime: Stop running gs during the GCscan phase.
Ensure that all gs are in a scan state when their stacks are being scanned.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/179160044
2014-11-21 16:46:27 -05:00
Russ Cox
8c3f64022a [dev.garbage] runtime: add prefetcht0, prefetcht1, prefetcht2, prefetcht3, prefetchnta for GC
We don't know what we need yet, so add them all.
Add them even on x86 architectures (as no-ops) so that
the GC can refer to them unconditionally.

Eventually we'll know what we want and probably
have just one 'prefetch' with an appropriate meaning
on each architecture.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/179160043
2014-11-21 15:57:10 -05:00
David du Colombier
e9c57d8a2d [dev.cc] runtime: convert Plan 9 port to Go
Thanks to Aram Hăvărneanu, Nick Owens
and Russ Cox for the early reviews.

LGTM=aram, rsc
R=rsc, lucio.dere, aram, ality
CC=golang-codereviews, mischief
https://golang.org/cl/175370043
2014-11-21 19:39:01 +01:00
Russ Cox
ad8179281d [dev.cc] runtime: convert nacl support to Go
LGTM=dave
R=minux, dave
CC=golang-codereviews
https://golang.org/cl/181030043
2014-11-21 10:22:18 -05:00
Alex Brainman
841de809bb [dev.cc] runtime: windows does not use _cgo_setenv and _cgo_unsetenv
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/175480043
2014-11-21 15:59:22 +11:00
Alex Brainman
0a38b2cdaf [dev.cc] runtime: fix windows goenvs conversion mistake
uint16 occupies 2 bytes, not 1

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/178100043
2014-11-21 12:15:18 +11:00
Rick Hudson
cc73a44f67 [dev.garbage] runtime: Fix constant overflow on 32 bit machines
LGTM=rsc
R=golang-codereviews
CC=golang-codereviews, rsc
https://golang.org/cl/180040043
2014-11-20 14:24:01 -05:00
Rick Hudson
8cfb084534 [dev.garbage] runtime: Turn concurrent GC on by default. Avoid write barriers for GC internal structures such as free lists.
LGTM=rsc
R=rsc
CC=golang-codereviews, rsc
https://golang.org/cl/179000043
2014-11-20 12:08:13 -05:00
Russ Cox
50e0749f87 [dev.cc] all: merge default (e4ab8f908aac) into dev.cc
TBR=austin
CC=golang-codereviews
https://golang.org/cl/179040044
2014-11-20 11:48:08 -05:00
Dmitriy Vyukov
2b3f379080 runtime: fix atomic operations on non-heap addresses
Race detector runtime does not tolerate operations on addresses
that was not previously declared with __tsan_map_shadow
(namely, data, bss and heap). The corresponding address
checks for atomic operations were removed in
https://golang.org/cl/111310044
Restore these checks.
It's tricker than just not calling into race runtime,
because it is the race runtime that makes the atomic
operations themselves (if we do not call into race runtime
we skip the atomic operation itself as well). So instead we call
__tsan_go_ignore_sync_start/end around the atomic operation.
This forces race runtime to skip all other processing
except than doing the atomic operation itself.
Fixes #9136.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/179030043
2014-11-20 09:51:02 -05:00
Alex Brainman
ab4578adef [dev.cc] runtime: convert remaining windows C code to Go
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/177090043
2014-11-20 12:24:03 +11:00
Russ Cox
378c2515ae runtime: remove assumption that noptrdata data bss noptrbss are ordered and contiguous
The assumption can be violated by external linkers reordering them or
inserting non-Go sections in between them. I looked briefly at trying
to write out the _go_.o in external linking mode in a way that forced
the ordering, but no matter what there's no way to force Go's data
and Go's bss to be next to each other. If there is any data or bss from
non-Go objects, it's very likely to get stuck in between them.

Instead, rewrite the two places we know about that make the assumption.
I grepped for noptrdata to look for more and didn't find any.

The added race test (os/exec in external linking mode) fails without
the changes in the runtime. It crashes with an invalid pointer dereference.

Fixes #9133.

LGTM=dneil
R=dneil
CC=dvyukov, golang-codereviews, iant
https://golang.org/cl/179980043
2014-11-19 15:25:33 -05:00
Austin Clements
f4a525452e [dev.cc] runtime: add explicit siginfo.si_addr field
struct siginfo_t's si_addr field is part of a union.
Previously, we represented this union in Go using an opaque
byte array and accessed the si_addr field using unsafe (and
wrong on 386 and arm!) pointer arithmetic.  Since si_addr is
the only field we use from this union, this replaces the
opaque byte array with an explicit declaration of the si_addr
field and accesses it directly.

LGTM=minux, rsc
R=rsc, minux
CC=golang-codereviews
https://golang.org/cl/179970044
2014-11-19 14:56:49 -05:00
Austin Clements
d11a425959 [dev.cc] runtime: decode power64 branch instructions the way the CPU does
Previously, this used the top 8 bits of an instruction as a
sort-of opcode and ignored the top two bits of the relative
PC.  This worked because these jumps are always negative and
never big enough for the top two bits of the relative PC (also
the bottom 2 bits of the sort-of opcode) to be anything other
than 0b11, but the code is confusing because it doesn't match
the actual structure of the instruction.

Instead, use the real 6 bit opcode and use all 24 bits of
relative PC.

LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/179960043
2014-11-19 14:24:41 -05:00
Austin Clements
b76e836042 [dev.cc] runtime: allow more address bits in lfstack on Power64
Previously, lfstack assumed Linux limited user space addresses
to 43 bits on Power64 based on a paper from 2001.  It turns
out the limit is now 46 bits, so lfstack was truncating
pointers.

Raise the limit to 48 bits (for some future proofing and to
make it match amd64) and add a self-test that will fail in a
useful way if ever unpack(pack(x)) != x.

With this change, dev.cc passes all.bash on power64le.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/174430043
2014-11-19 11:30:58 -05:00
Alex Brainman
b27c0618eb [dev.cc] runtime: update sys_windows_386.s and sys_windows_amd64.s for Go conversion
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/176970043
2014-11-19 11:55:15 +11:00
Austin Clements
f4627d1b05 [dev.cc] runtime: merge power64 onM/onM_signalok into systemstack
This is the power64 component of CL 174950043.

With this, dev.cc compiles on power64 and power64le and passes
most tests if GOGC=off (but crashes in go_bootstrap if GC is
on).

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/175290043
2014-11-18 15:50:36 -05:00
Austin Clements
70f6769b60 [dev.cc] runtime: catch defs_linux_power64*.go up to other archs
Fix a constant conversion error.  Add set_{sec,nsec} for
timespec and set_usec for timeval.  Fix type of
sigaltstackt.ss_size.

LGTM=rsc
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/180840043
2014-11-18 15:19:48 -05:00
Austin Clements
0da27cb8b0 [dev.cc] runtime: convert power64-specific .c and .h files to Go
The power64 equivalent of CL 174860043

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/179890043
2014-11-18 15:19:37 -05:00
Austin Clements
3f27c3ae37 [dev.cc] runtime: convert power64 assembly files for C to Go transition
The power64 equivalent of CL 168510043

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/178940043
2014-11-18 15:19:26 -05:00
Austin Clements
54d731452d [dev.cc] runtime: convert power64 signal handlers from C to Go
The power64 equivalent of CL 168500044

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/175280043
2014-11-18 15:19:09 -05:00
Russ Cox
0fe444d3e8 [dev.cc] runtime: generate GOOS- and GOARCH-specific files with go generate
Eventually I'd like almost everything cmd/dist generates
to be done with 'go generate' and checked in, to simplify
the bootstrap process. The only thing cmd/dist really needs
to do is write things like the current experiment info and
the current version.

This is a first step toward that. It replaces the _NaCl etc
constants with generated ones goos_nacl, goos_darwin,
goarch_386, and so on.

LGTM=dave, austin
R=austin, dave, bradfitz
CC=golang-codereviews, iant, r
https://golang.org/cl/174290043
2014-11-18 12:07:50 -05:00
Russ Cox
312a64ec4e [dev.cc] runtime: convert defs_linux_power64*.h to go
LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/176990043
2014-11-18 11:38:23 -05:00
Austin Clements
0e8fed098c [dev.cc] runtime: two missed references to "M stack"
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/177940043
2014-11-18 09:54:50 -05:00
Alex Brainman
55f19ed866 runtime: fix getcallersp documentation
LGTM=bradfitz
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/180760043
2014-11-18 09:55:15 +11:00
Alex Brainman
fc288681cf [dev.cc] runtime: replace deleted netpollfd function
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/169710043
2014-11-17 17:18:21 +11:00
Russ Cox
3034be60d8 [dev.garbage] all: merge dev.cc (723ca3789b88) into dev.garbage
Brings in Linux time signature fixes. Should fix build.

TBR=austin
CC=golang-codereviews
https://golang.org/cl/176870043
2014-11-16 16:53:53 -05:00
Russ Cox
b3932baba4 runtime: fix sudog leak
The SudoG used to sit on the stack, so it was cheap to allocated
and didn't need to be cleaned up when finished.

For the conversion to Go, we had to move sudog off the stack
for a few reasons, so we added a cache of recently used sudogs
to keep allocation cheap. But we didn't add any of the necessary
cleanup before adding a SudoG to the new cache, and so the cached
SudoGs had stale pointers inside them that have caused all sorts
of awful, hard to debug problems.

CL 155760043 made sure SudoG.elem is cleaned up.
CL 150520043 made sure SudoG.selectdone is cleaned up.

This CL makes sure SudoG.next, SudoG.prev, and SudoG.waitlink
are cleaned up. I should have done this when I did the other two
fields; instead I wasted a week tracking down a leak they caused.

A dangling SudoG.waitlink can point into a sudogcache list that
has been "forgotten" in order to let the GC collect it, but that
dangling .waitlink keeps the list from being collected.
And then the list holding the SudoG with the dangling waitlink
can find itself in the same situation, and so on. We end up
with lists of lists of unusable SudoGs that are still linked into
the object graph and never collected (given the right mix of
non-trivial selects and non-channel synchronization).

More details in golang.org/issue/9110.

Fixes #9110.

LGTM=r
R=r
CC=dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/177870043
2014-11-16 16:44:45 -05:00
Russ Cox
6150414cb8 runtime: update URL for heap dump format
I just created that redirect, so we can change
it once the wiki moves.

LGTM=bradfitz, khr
R=khr, bradfitz
CC=golang-codereviews
https://golang.org/cl/177780043
2014-11-16 14:25:33 -05:00
Russ Cox
0fcf54b3d2 [dev.garbage] all: merge dev.cc into dev.garbage
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
2014-11-15 08:00:38 -05:00
Dave Cheney
2ceca80e3f [dev.cc] runtime: fix _sfloat thunk
* _sfloat dispatches to runtime._sfloat2 with the Go calling convention, so the seecond argument is a [15]uint32, not a *[15]uint32.
* adjust _sfloat2 to return the new pc in 68(R13) as expected.

LGTM=rsc
R=minux, austin, rsc
CC=golang-codereviews
https://golang.org/cl/174160043
2014-11-15 13:27:05 +11:00
Dave Cheney
14d23bfd7b [dev.cc] runtime: fix bus error accessing auxv random data on arm5
It's rather unsporting of the kernel to give us a pointer to unaligned memory.

This fixes one crash, the next crash occurs in the soft float emulation.

LGTM=minux, rsc, austin
R=minux, rsc, austin
CC=golang-codereviews
https://golang.org/cl/177730043
2014-11-15 09:57:02 +11:00
Russ Cox
580cba42f4 [dev.cc] runtime: change set_sec to take int64
Fixes build.
Tested that all these systems can make.bash.

TBR=austin
CC=golang-codereviews
https://golang.org/cl/177770043
2014-11-14 14:50:00 -05:00
Russ Cox
5fce15a2a3 [dev.cc] runtime: fix lfstack for amd64 addresses in top half of addr space
While we are here, add the linux/power64 version.

LGTM=austin
R=austin
CC=aram, dvyukov, golang-codereviews
https://golang.org/cl/177750043
2014-11-14 12:55:23 -05:00
Russ Cox
a87e4a2d01 [dev.cc] runtime: fix linux build
TBR=austin
CC=golang-codereviews
https://golang.org/cl/176760044
2014-11-14 12:55:10 -05:00
Joel Sing
1d05d5880e [dev.cc] runtime: convert dragonfly/amd64 port to Go
LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews
https://golang.org/cl/176750043
2014-11-15 04:47:20 +11:00
Russ Cox
3e804631d9 [dev.cc] all: merge dev.power64 (7667e41f3ced) into dev.cc
This is to reduce the delta between dev.cc and dev.garbage to just garbage collector changes.

These are the files that had merge conflicts and have been edited by hand:
        malloc.go
        mem_linux.go
        mgc.go
        os1_linux.go
        proc1.go
        panic1.go
        runtime1.go

LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/174180043
2014-11-14 12:10:52 -05:00
Russ Cox
9ef4e56108 [dev.garbage] all: merge dev.power64 (7667e41f3ced) into dev.garbage
Now the only difference between dev.cc and dev.garbage
is the runtime conversion on the one side and the
garbage collection on the other. They both have the
same set of changes from default and dev.power64.

LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/172570043
2014-11-14 12:09:42 -05:00
Joel Sing
9ad6b7e322 [dev.cc] runtime: convert openbsd/386 port to Go
LGTM=rsc
R=golang-codereviews, bradfitz, rsc
CC=golang-codereviews
https://golang.org/cl/173200044
2014-11-15 03:55:14 +11:00
Russ Cox
3dcc62e1da [dev.garbage] all: merge default (f38460037b72) into dev.garbage
This is the revision that dev.cc is branched from.

LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/169590043
2014-11-14 11:37:54 -05:00
Aram Hăvărneanu
9d6825edee [dev.cc] runtime: fix nil pointer crash handler bug on Solaris
This change fixes the Solaris port.

LGTM=dave, rsc
R=rsc, dave
CC=brad, golang-codereviews
https://golang.org/cl/168600045
2014-11-14 14:25:49 +01:00
Alex Brainman
0438182c30 [dev.cc] runtime: convert netpoll_windows.c to Go
LGTM=rsc
R=rsc
CC=dvyukov, golang-codereviews
https://golang.org/cl/172530043
2014-11-14 14:07:28 +11:00
Joel Sing
ba603c3100 [dev.cc] runtime: convert openbsd/amd64 port to Go
LGTM=rsc
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/171660043
2014-11-14 13:01:12 +11:00
Joel Sing
b2ec4cf50c [dev.cc] runtime: make SIGSYS notifiable on freebsd (again)
This was originally done to the C port in rev 17d3b45534b5 and
seemingly got lost during the conversion.

LGTM=bradfitz
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/167700043
2014-11-14 04:29:03 +11:00
Aram Hăvărneanu
e088e16256 [dev.cc] runtime: convert Solaris port to Go
Memory management was consolitated with the BSD ports, since
it was almost identical.

Assembly thunks are gone, being replaced by the new //go:linkname
feature.

This change supersedes CL 138390043 (runtime: convert solaris
netpoll to Go), which was previously reviewed and tested.

This change is only the first step, the port now builds,
but doesn't run. Binaries fail to exec:

    ld.so.1: 6.out: fatal: 6.out: TLS requirement failure : TLS support is unavailable
    Killed

This seems to happen because binaries don't link with libc.so
anymore. We will have to solve that in a different CL.

Also this change is just a rough translation of the original
C code, cleanup will come in a different CL.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=rsc
R=rsc, dave
CC=golang-codereviews, iant, khr, minux, r, rlh
https://golang.org/cl/174960043
2014-11-13 16:07:10 +01:00
Alex Brainman
a0862a175d [dev.cc] runtime: convert mem_windows.c to Go
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/175000043
2014-11-13 14:53:13 +11:00
Alex Brainman
e5d01a5ffc [dev.cc] runtime: add missing cb_max const
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/169490043
2014-11-13 12:05:36 +11:00
Joel Sing
37cae806cb [dev.cc] [dev.cc] runtime: fix freebsd cgo __progname export
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/174050043
2014-11-12 17:18:22 -05:00
Russ Cox
656be317d0 [dev.cc] runtime: delete scalararg, ptrarg; rename onM to systemstack
Scalararg and ptrarg are not "signal safe".
Go code filling them out can be interrupted by a signal,
and then the signal handler runs, and if it also ends up
in Go code that uses scalararg or ptrarg, now the old
values have been smashed.
For the pieces of code that do need to run in a signal handler,
we introduced onM_signalok, which is really just onM
except that the _signalok is meant to convey that the caller
asserts that scalarg and ptrarg will be restored to their old
values after the call (instead of the usual behavior, zeroing them).

Scalararg and ptrarg are also untyped and therefore error-prone.

Go code can always pass a closure instead of using scalararg
and ptrarg; they were only really necessary for C code.
And there's no more C code.

For all these reasons, delete scalararg and ptrarg, converting
the few remaining references to use closures.

Once those are gone, there is no need for a distinction between
onM and onM_signalok, so replace both with a single function
equivalent to the current onM_signalok (that is, it can be called
on any of the curg, g0, and gsignal stacks).

The name onM and the phrase 'm stack' are misnomers,
because on most system an M has two system stacks:
the main thread stack and the signal handling stack.

Correct the misnomer by naming the replacement function systemstack.

Fix a few references to "M stack" in code.

The main motivation for this change is to eliminate scalararg/ptrarg.
Rick and I have already seen them cause problems because
the calling sequence m.ptrarg[0] = p is a heap pointer assignment,
so it gets a write barrier. The write barrier also uses onM, so it has
all the same problems as if it were being invoked by a signal handler.
We worked around this by saving and restoring the old values
and by calling onM_signalok, but there's no point in keeping this nice
home for bugs around any longer.

This CL also changes funcline to return the file name as a result
instead of filling in a passed-in *string. (The *string signature is
left over from when the code was written in and called from C.)
That's arguably an unrelated change, except that once I had done
the ptrarg/scalararg/onM cleanup I started getting false positives
about the *string argument escaping (not allowed in package runtime).
The compiler is wrong, but the easiest fix is to write the code like
Go code instead of like C code. I am a bit worried that the compiler
is wrong because of some use of uninitialized memory in the escape
analysis. If that's the reason, it will go away when we convert the
compiler to Go. (And if not, we'll debug it the next time.)

LGTM=khr
R=r, khr
CC=austin, golang-codereviews, iant, rlh
https://golang.org/cl/174950043
2014-11-12 14:54:31 -05:00
Russ Cox
e98f2d597e [dev.cc] runtime/cgo: add comment about import _ "unsafe"
LGTM=bradfitz, r
R=r, bradfitz
CC=golang-codereviews
https://golang.org/cl/167650043
2014-11-12 14:54:04 -05:00
Rick Hudson
18ed947ee1 [dev.garbage] runtime: Add write barriers to c code
Also improve missing GC mark diagnostics.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/169450043
2014-11-12 14:20:53 -05:00
Russ Cox
a9695a5d38 [dev.cc] runtime/cgo: fix freebsd build?
Last try and then someone with a FreeBSD has to do it.

TBR=r
CC=golang-codereviews
https://golang.org/cl/171590043
2014-11-11 23:28:26 -05:00
Russ Cox
9e719ceefe [dev.cc] runtime: fix arm5 build
TBR=r
CC=golang-codereviews
https://golang.org/cl/168600043
2014-11-11 23:24:54 -05:00
Russ Cox
22293bb1a4 [dev.cc] runtime/cgo: add missing import _ "unsafe" for //go:linkname
Will prod freebsd build along.
Not claiming it will fix it.

TBR=r
CC=golang-codereviews
https://golang.org/cl/171580044
2014-11-11 23:19:59 -05:00
Russ Cox
aac17fd4e1 [dev.cc] runtime: convert freebsd to Go
It builds.
Don't know if it works, but it's a lot closer than having everything in C.

LGTM=r
R=r
CC=golang-codereviews
https://golang.org/cl/168590043
2014-11-11 23:00:29 -05:00
Russ Cox
c81d248eca [dev.cc] runtime: convert softfloat_arm.c to Go + build fixes
Also include onM_signalok fix from issue 8995.

Fixes linux/arm build.
Fixes #8995.

LGTM=r
R=r, dave
CC=golang-codereviews
https://golang.org/cl/168580043
2014-11-11 22:30:02 -05:00
Russ Cox
8420df622a [dev.cc] runtime: bring back mgc0.h
This was recorded as an hg mv instead of an hg cp.
For now a C version is needed for the Go compiler.

TBR=r
CC=golang-codereviews
https://golang.org/cl/174020043
2014-11-11 18:50:02 -05:00
Russ Cox
9204821731 [dev.cc] runtime: convert arch-specific .c and .h files to Go
The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.

vlrt.c was only called from C. Pure delete.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r, austin
CC=dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/174860043
2014-11-11 17:09:09 -05:00
Russ Cox
e785e3acf8 [dev.cc] runtime: convert operating system support code from C to Go
The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/174830044
2014-11-11 17:08:54 -05:00
Russ Cox
b2cdf30eb6 [dev.cc] runtime: convert scheduler from C to Go
The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r, daniel.morsing
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/172260043
2014-11-11 17:08:33 -05:00
Russ Cox
59e3e5354d [dev.cc] runtime: convert race implementation from C to Go
The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/172250044
2014-11-11 17:08:14 -05:00
Russ Cox
ece09790af [dev.cc] runtime: convert parallel support code from C to Go
The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r, austin
CC=dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/172250043
2014-11-11 17:07:54 -05:00
Russ Cox
580ef3e4af [dev.cc] runtime: convert defs_$GOOS_$GOARCH.h to Go
The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.

In a few cases, defs_$GOOS_$GOARCH.go already existed,
so the target here is defs1_$GOOS_$GOARCH.go.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/171490043
2014-11-11 17:07:37 -05:00
Russ Cox
0c3c2c1724 [dev.cc] runtime: convert basic library routines from C to Go
float.c held bit patterns for special float64 values,
hiding from the real uses. Rewrite Go code not to
refer to those values directly.

Convert library routines in runtime.c and string.c.

LGTM=r
R=r, dave
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/170330043
2014-11-11 17:07:06 -05:00
Russ Cox
15ced2d008 [dev.cc] runtime: convert assembly files for C to Go transition
The main change is that #include "zasm_GOOS_GOARCH.h"
is now #include "go_asm.h" and/or #include "go_tls.h".

Also, because C StackGuard is now Go _StackGuard,
the assembly name changes from const_StackGuard to
const__StackGuard.

In asm_$GOARCH.s, add new function getg, formerly
implemented in C.

The renamed atomics now have Go wrappers, to get
escape analysis annotations right. Those wrappers
are in CL 174860043.

LGTM=r, aram
R=r, aram
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/168510043
2014-11-11 17:06:22 -05:00
Russ Cox
2d917c0c26 [dev.cc] runtime: convert signal handlers from C to Go
This code overused macros and could not be
converted automatically. Instead a new sigctxt
type had to be defined for each os/arch combination,
with a common (implicit) interface used by the
arch-specific signal handler code.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/168500044
2014-11-11 17:05:55 -05:00
Russ Cox
9f99d531a0 [dev.cc] runtime/cgo: convert from C to Go
The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/168500043
2014-11-11 17:05:37 -05:00
Russ Cox
fee9e47559 [dev.cc] runtime: convert header files to Go
The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r, austin
CC=dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/167550043
2014-11-11 17:05:19 -05:00
Russ Cox
1e2d2f0947 [dev.cc] runtime: convert memory allocator and garbage collector to Go
The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/167540043
2014-11-11 17:05:02 -05:00
Russ Cox
d98553a727 [dev.cc] runtime: convert panic and stack code from C to Go
The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r, dave
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/166520043
2014-11-11 17:04:34 -05:00
Russ Cox
9eded54fa3 [dev.garbage] runtime: concurrent mark fixes
Add missing write barrier when initializing state
for newly created goroutine. Add write barrier for
same slot when preempting a goroutine.

Disable write barrier during goroutine death,
because dopanic does pointer writes.

With concurrent mark enabled (not in this CL), all.bash passed once.
The second time, TestGoexitCrash-2 failed.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/167610043
2014-11-11 16:54:50 -05:00
Russ Cox
0d49f7b5fc [dev.cc] cmd/dist: adjust for build process without cmd/cc
[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

- Remove references to C compiler directories.
- Remove generation of special header files.
- Remove generation of Go source files from C declarations.

- Compile Go sources before rest of package (was after),
  so that Go compiler can write go_asm.h for use in assembly.

- Move TLS information from cmd/dist (was embedding in output)
  to src/runtime/go_tls.h, which it can be maintained directly.

LGTM=r
R=r, dave
CC=austin, golang-codereviews, iant, khr
https://golang.org/cl/172960043
2014-11-11 01:29:05 -05:00
Russ Cox
33e910296e [dev.cc] reflect: interfaces contain only pointers
[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

Adjustments for changes made in CL 169360043.
This change is already present in the dev.garbage branch.

LGTM=r
R=r
CC=austin, golang-codereviews, iant, khr
https://golang.org/cl/167520044
2014-11-11 01:23:01 -05:00
Russ Cox
37186d91fa [dev.garbage] runtime: add write barrier to casp
Also rewrite some casp that don't use real pointers
to use casuintptr instead.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/166440044
2014-11-10 14:59:36 -05:00
Rick Hudson
28c5385965 [dev.garbage] runtime: Coarsen the write barrier to always grey the destination.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/174820043
2014-11-10 14:32:02 -05:00
Rick Hudson
d3d60975b4 [dev.garbage] runtime: Code to implement write barriers
To turn concurrent gc on alter the if false in func gogc
currently at line 489 in malloc.go

LGTM=rsc
R=rsc
CC=golang-codereviews, rlh
https://golang.org/cl/172190043
2014-11-10 13:42:34 -05:00
Russ Cox
2ad99f0960 runtime: fix sudog leak in syncsemrelease
Manifested as increased memory usage in a Google production system.

Not an unbounded leak, but can significantly increase the number
of sudogs allocated between garbage collections.

I checked all the other calls to acquireSudog.
This is the only one that was missing a releaseSudog.

LGTM=r, dneil
R=dneil, r
CC=golang-codereviews
https://golang.org/cl/169260043
2014-11-09 20:21:03 -05:00
Russ Cox
2cd05c3404 runtime/cgo: add +build tags to files named for $GOOS
These are being built into the runtime/cgo for every
operating system. It doesn't seem to matter, but
restore the Go 1.3 behavior anyway.

LGTM=r
R=r, dave
CC=golang-codereviews
https://golang.org/cl/171290043
2014-11-09 20:20:45 -05:00
Andrew Gerrand
7f0be1f781 all: use golang.org/x/... import paths
LGTM=rsc, r
R=r, rsc
CC=golang-codereview, golang-codereviews
https://golang.org/cl/168050043
2014-11-10 09:15:57 +11:00
Keith Randall
5b110c7b08 runtime: don't stop bitmap dump at BitsDead
Stack bitmaps need to be scanned past any BitsDead entries.

Object bitmaps will not have any BitsDead in them (bitmap extraction stops at
the first BitsDead entry in makeheapobjbv).  data/bss bitmaps also have no BitsDead entries.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/168270043
2014-11-06 09:30:41 -08:00
Russ Cox
6ad16c4a48 runtime: fix initial gp->sched.pc in newextram
CL 170720043 missed this one when adding +PCQuantum.

LGTM=iant
R=r, iant
CC=golang-codereviews
https://golang.org/cl/168090043
2014-11-06 09:37:04 -05:00
Russ Cox
39bcbb353c runtime: avoid gentraceback of self on user goroutine stack
Gentraceback may grow the stack.
One of the gentraceback wrappers may grow the stack.
One of the gentraceback callback calls may grow the stack.
Various stack pointers are stored in various stack locations
as type uintptr during the execution of these calls.
If the stack does grow, these stack pointers will not be
updated and will start trying to decode stack memory that
is no longer valid.

It may be possible to change the type of the stack pointer
variables to be unsafe.Pointer, but that's pretty subtle and
may still have problems, even if we catch every last one.
An easier, more obviously correct fix is to require that
gentraceback of the currently running goroutine must run
on the g0 stack, not on the goroutine's own stack.

Not doing this causes faults when you set
        StackFromSystem = 1
        StackFaultOnFree = 1

The new check in gentraceback will catch future lapses.

The more general problem is calling getcallersp but then
calling a function that might relocate the stack, which would
invalidate the result of getcallersp. Add note to stubs.go
declaration of getcallersp explaining the problem, and
check all existing calls to getcallersp. Most needed fixes.

This affects Callers, Stack, and nearly all the runtime
profiling routines. It does not affect stack copying directly
nor garbage collection.

LGTM=khr
R=khr, bradfitz
CC=golang-codereviews, r
https://golang.org/cl/167060043
2014-11-05 23:01:48 -05:00
Russ Cox
75d3f62b3c [dev.garbage] cmd/gc, runtime: add locks around print statements
Now each C printf, Go print, or Go println is guaranteed
not to be interleaved with other calls of those functions.
This should help when debugging concurrent failures.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/169120043
2014-11-05 14:42:54 -05:00
Russ Cox
91658f934d [dev.garbage] runtime: ignore objects in dead spans
We still don't know why this is happening.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/169990043
2014-11-05 14:42:24 -05:00
Russ Cox
0584312e7d [dev.garbage] runtime: fix a few checkmark bugs
- Some sequencing issues with stopping the first gc_m round
at the right place to set up correctly for the second round.

- atomicxor8 is not idempotent; avoid xor.

- Maintain BitsDead type bits correctly; see long comment added.

- Enable checkmark phase by default for now.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/171090043
2014-11-05 13:37:34 -05:00
Russ Cox
e1f7c3f82f [dev.garbage] runtime: fix 32-bit build
TBR=crawshaw
R=crawshaw
CC=golang-codereviews
https://golang.org/cl/168860046
2014-11-05 11:09:08 -05:00
Rick Hudson
77db737ac3 [dev.garbage] runtime: Add gc mark verification pass.
This adds an independent mark phase to the GC that can be used to
verify the the default concurrent mark phase has found all reachable
objects. It uses the upper 2 bits of the boundary nibble to encode
the mark leaving the lower bits to encode the boundary and the
normal mark bit.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/167130043
2014-11-04 13:31:34 -05:00
Austin Clements
489ff75ab8 runtime: make Go and C mallocgc signatures match
Previously, the flags argument to mallocgc was an int in Go,
but a uint32 in C.  Change the Go type to use uint32 so these
agree.  The largest flag value is 2 (and of course no flag
values are negative), so this won't change anything on little
endian architectures, but it matters on big endian.

LGTM=rsc
R=khr, rsc
CC=golang-codereviews
https://golang.org/cl/169920043
2014-11-03 13:26:46 -05:00
Austin Clements
31b1207fde [dev.power64] all: merge default into dev.power64
Trivial merge except for src/runtime/asm_power64x.s and
src/runtime/signal_power64x.c

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/168950044
2014-11-03 10:53:11 -05:00
Austin Clements
e1db508ffd [dev.power64] runtime: fix gcinfo_test on power64x
The GC info masks for slices and strings were changed in
commit caab29a25f68, but the reference masks used by
gcinfo_test for power64x hadn't caught up.  Now they're
identical to amd64, so this CL fixes this test by combining
the reference masks for these platforms.

LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/162620044
2014-10-31 16:58:12 -04:00
Austin Clements
40a5b3ecb1 [dev.power64] runtime: fix fastrand1 on power64x
fastrand1 depends on testing the high bit of its uint32 state.
For efficiency, all of the architectures implement this as a
sign bit test.  However, on power64, fastrand1 was using a
64-bit sign test on the zero-extended 32-bit state.  This
always failed, causing fastrand1 to have very short periods
and often decay to 0 and get stuck.

Fix this by using a 32-bit signed compare instead of a 64-bit
compare.  This fixes various tests for the randomization of
select of map iteration.

LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/166990043
2014-10-31 13:39:36 -04:00
Austin Clements
6e86003651 [dev.power64] 9g: fix under-zeroing in clearfat
All three cases of clearfat were wrong on power64x.

The cases that handle 1032 bytes and up and 32 bytes and up
both use MOVDU (one directly generated in a loop and the other
via duffzero), which leaves the pointer register pointing at
the *last written* address.  The generated code was not
accounting for this, so the byte fill loop was re-zeroing the
last zeroed dword, rather than the bytes following the last
zeroed dword.  Fix this by simply adding an additional 8 byte
offset to the byte zeroing loop.

The case that handled under 32 bytes was also wrong.  It
didn't update the pointer register at all, so the byte zeroing
loop was simply re-zeroing the beginning of region.  Again,
the fix is to add an offset to the byte zeroing loop to
account for this.

LGTM=dave, bradfitz
R=rsc, dave, bradfitz
CC=golang-codereviews
https://golang.org/cl/168870043
2014-10-31 11:08:27 -04:00
Austin Clements
c24156bafe [dev.power64] runtime: fix a syntax error that slipped in to asm_power64x.s
Apparently I had already moved on to fixing another problem
when I submitted CL 169790043.

LGTM=dave
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/165210043
2014-10-30 16:44:42 -04:00
Austin Clements
8a09639ae8 [dev.power64] runtime: make asm_power64x.s go vet-clean
No real problems found.  Just lots of argument names that
didn't quite match up.

LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/169790043
2014-10-30 15:58:30 -04:00
Austin Clements
4cf28a11e3 [dev.power64] runtime: fix out-of-date comment in panic
LGTM=bradfitz
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/162500043
2014-10-30 12:08:21 -04:00
Austin Clements
36d417c0e3 [dev.power64] runtime: test CAS on large unsigned 32-bit numbers
This adds a test to runtime·check to ensure CAS of large
unsigned 32-bit numbers does not accidentally sign-extend its
arguments.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/162490044
2014-10-30 11:17:26 -04:00
Austin Clements
097362fd2e [dev.power64] runtime: match argument/return type signedness in power64x assembly
Previously, the power64x runtime assembly was sloppy about
using sign-extending versus zero-extending moves of arguments
and return values.  I think all of the cases that actually
mattered have been fixed in recent CLs; this CL fixes up the
few remaining mismatches.

LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/162480043
2014-10-30 10:45:41 -04:00
Russ Cox
b035e97315 [dev.garbage] cmd/gc, runtime: implement write barriers in terms of writebarrierptr
This CL implements the many multiword write barriers by calling
writebarrierptr, so that only writebarrierptr needs the actual barrier.
In lieu of an actual barrier, writebarrierptr checks that the value
being copied is not a small non-zero integer. This is enough to
shake out bugs where the barrier is being called when it should not
(for non-pointer values). It also found a few tests in sync/atomic
that were being too clever.

This CL adds a write barrier for the memory moved during the
builtin copy function, which I forgot when inserting barriers for Go 1.4.

This CL re-enables some write barriers that were disabled for Go 1.4.
Those were disabled because it is possible to change the generated
code so that they are unnecessary most of the time, but we have not
changed the generated code yet. For safety they must be enabled.

None of this is terribly efficient. We are aiming for correct first.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/168770043
2014-10-30 10:16:03 -04:00
Russ Cox
a5a0733144 runtime: change top-most return PC from goexit to goexit+PCQuantum
If you get a stack of PCs from Callers, it would be expected
that every PC is immediately after a call instruction, so to find
the line of the call, you look up the line for PC-1.
CL 163550043 now explicitly documents that.

The most common exception to this is the top-most return PC
on the stack, which is the entry address of the runtime.goexit
function. Subtracting 1 from that PC will end up in a different
function entirely.

To remove this special case, make the top-most return PC
goexit+PCQuantum and then implement goexit in assembly
so that the first instruction can be skipped.

Fixes #7690.

LGTM=r
R=r
CC=golang-codereviews
https://golang.org/cl/170720043
2014-10-29 20:37:44 -04:00
Alex Brainman
f9c4c16dce runtime: make TestCgoExternalThreadPanic run on windows
LGTM=rsc
R=golang-codereviews, bradfitz, rsc
CC=golang-codereviews
https://golang.org/cl/163540043
2014-10-30 10:24:37 +11:00
Russ Cox
a22c11b995 runtime: fix line number in first stack frame in printed stack trace
Originally traceback was only used for printing the stack
when an unexpected signal came in. In that case, the
initial PC is taken from the signal and should be used
unaltered. For the callers, the PC is the return address,
which might be on the line after the call; we subtract 1
to get to the CALL instruction.

Traceback is now used for a variety of things, and for
almost all of those the initial PC is a return address,
whether from getcallerpc, or gp->sched.pc, or gp->syscallpc.
In those cases, we need to subtract 1 from this initial PC,
but the traceback code had a hard rule "never subtract 1
from the initial PC", left over from the signal handling days.

Change gentraceback to take a flag that specifies whether
we are tracing a trap.

Change traceback to default to "starting with a return PC",
which is the overwhelmingly common case.

Add tracebacktrap, like traceback but starting with a trap PC.

Use tracebacktrap in signal handlers.

Fixes #7690.

LGTM=iant, r
R=r, iant
CC=golang-codereviews
https://golang.org/cl/167810044
2014-10-29 15:14:24 -04:00
Russ Cox
8db71d4ee8 runtime: update comment for Callers
Attempt to clear up confusion about how to turn
the PCs reported by Callers into the file and line
number people actually want.

Fixes #7690.

LGTM=r, chris.cs.guy
R=r, chris.cs.guy
CC=golang-codereviews
https://golang.org/cl/163550043
2014-10-29 15:14:04 -04:00
Russ Cox
d6f4e5020b [dev.garbage] all: merge dev.power64 (5ad5e85cfb99) into dev.garbage
The goal here is to get the big-endian fixes so that
in some upcoming code movement for write barriers
I don't make them unmergeable.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/166890043
2014-10-29 12:25:24 -04:00
Russ Cox
8e171e1966 [dev.garbage] all: merge default (dd5014ed9b01) into dev.garbage
LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/170730043
2014-10-29 11:54:48 -04:00
Russ Cox
599199fd9f [dev.power64] all: merge default (dd5014ed9b01) into dev.power64
Still passes on amd64.

LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/165110043
2014-10-29 11:45:01 -04:00
Russ Cox
3ce6a4fb97 runtime: fix windows build
TBR=austin
CC=golang-codereviews
https://golang.org/cl/167820043
2014-10-29 00:02:29 -04:00
Russ Cox
8fcdc70c5e runtime: add GODEBUG invalidptr setting
Fixes #8861.
Fixes #8911.

LGTM=r
R=r
CC=golang-codereviews
https://golang.org/cl/165780043
2014-10-28 21:53:31 -04:00
Russ Cox
c4efaac15d runtime: fix unrecovered panic on external thread
Fixes #8588.

LGTM=austin
R=austin
CC=golang-codereviews, khr
https://golang.org/cl/159700044
2014-10-28 21:53:09 -04:00
Russ Cox
5e56854599 cmd/gc: avoid use of goprintf
goprintf is a printf-like print for Go.
It is used in the code generated by 'defer print(...)' and 'go print(...)'.

Normally print(1, 2, 3) turns into

        printint(1)
        printint(2)
        printint(3)

but defer and go need a single function call to give the runtime;
they give the runtime something like goprintf("%d%d%d", 1, 2, 3).

Variadic functions like goprintf cannot be described in the new
type information world, so we have to replace it.

Replace with a custom function, so that defer print(1, 2, 3) turns
into

        defer func(a1, a2, a3 int) {
                print(a1, a2, a3)
        }(1, 2, 3)

(and then the print becomes three different printints as usual).

Fixes #8614.

LGTM=austin
R=austin
CC=golang-codereviews, r
https://golang.org/cl/159700043
2014-10-28 21:52:53 -04:00
Russ Cox
b55791e200 [dev.power64] cmd/5a, cmd/6a, cmd/8a, cmd/9a: make labels function-scoped
I removed support for jumping between functions years ago,
as part of doing the instruction layout for each function separately.

Given that, it makes sense to treat labels as function-scoped.
This lets each function have its own 'loop' label, for example.

Makes the assembly much cleaner and removes the last
reason anyone would reach for the 123(PC) form instead.

Note that this is on the dev.power64 branch, but it changes all
the assemblers. The change will ship in Go 1.5 (perhaps after
being ported into the new assembler).

Came up as part of CL 167730043.

LGTM=r
R=r
CC=austin, dave, golang-codereviews, minux
https://golang.org/cl/159670043
2014-10-28 21:50:16 -04:00
Austin Clements
87b4149b22 [dev.power64] runtime: fix atomicor8 for power64x
Power64 servers do not currently support sub-word size atomic
memory access, so atomicor8 uses word size atomic access.
However, previously atomicor8 made no attempt to align this
access, resulting in errors.  Fix this by aligning the pointer
to a word boundary and shifting the value appropriately.
Since atomicor8 is used in GC, add a test to runtime·check to
make sure this doesn't break in the future.

This also fixes an incorrect branch label, an incorrectly
sized argument move, and adds argument names to help go vet.

LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/165820043
2014-10-28 15:57:33 -04:00
Russ Cox
202bf8d94d doc/asm: explain coordination with garbage collector
Also a few other minor changes.

Fixes #8712.

LGTM=r
R=r
CC=golang-codereviews
https://golang.org/cl/164150043
2014-10-28 15:51:06 -04:00
Jens Frederich
46af78915a runtime: add PauseEnd array to MemStats and GCStats
Fixes #8787.

LGTM=rsc
R=rsc, dvyukov
CC=golang-codereviews
https://golang.org/cl/153670043
2014-10-28 12:35:25 -04:00
Russ Cox
138b5ccd12 runtime: disable fake time on nacl
This leaked into the CL I submitted for Minux,
because I was testing it.

TBR=adg
CC=golang-codereviews
https://golang.org/cl/159600044
2014-10-27 20:47:15 -04:00
Shenghou Ma
2fe9482343 runtime: add fake time support back.
Revived from CL 15690048.

Fixes #5356.

LGTM=rsc
R=adg, dvyukov, rsc
CC=golang-codereviews
https://golang.org/cl/101400043
2014-10-27 20:35:15 -04:00
Dave Cheney
cb4f5e1970 [dev.power64] runtime: fix cas64 on power64x
cas64 was jumping to the wrong offset.

LGTM=minux, rsc
R=rsc, austin, minux
CC=golang-codereviews
https://golang.org/cl/158710043
2014-10-28 11:15:48 +11:00
Dave Cheney
1b130a08d8 [dev.power64] runtime: fix power64le build
Brings defs_linux_power64le.h up to date with the big endian version.

LGTM=rsc
R=rsc, austin
CC=golang-codereviews
https://golang.org/cl/161470043
2014-10-28 09:56:33 +11:00
Austin Clements
062e354c84 [dev.power64] runtime: power64 fixes and ports of changes
Fix include paths that got moved in the great pkg/ rename.  Add
missing runtime/arch_* files for power64.  Port changes that
happened on default since branching to
runtime/{asm,atomic,sys_linux}_power64x.s (precise stacks,
calling convention change, various new and deleted functions.
Port struct renaming and fix some bugs in
runtime/defs_linux_power64.h.

LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/161450043
2014-10-27 17:27:03 -04:00
Austin Clements
5a653089ef [dev.power64] all: merge default into dev.power64
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/164110043
2014-10-27 17:17:06 -04:00
Austin Clements
3e62d2184a runtime: fix endianness assumption when decoding ftab
The ftab ends with a half functab record consisting only of
the 'entry' field followed by a uint32 giving the offset of
the next table.  Previously, symtabinit assumed it could read
this uint32 as a uintptr.  Since this is unsafe on big endian,
explicitly read the offset as a uint32.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/157660043
2014-10-27 17:12:48 -04:00
Rick Hudson
5550249ad3 [dev.garbage] runtime: Fix 386 compiler warnings.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/163390043
2014-10-27 17:07:53 -04:00
Russ Cox
0f66d785cf [dev.garbage] runtime: fix TestLFStack on 386
LGTM=rlh
R=rlh, dvyukov
CC=golang-codereviews
https://golang.org/cl/157430044
2014-10-27 15:57:07 -04:00
Rick Hudson
6184f46ea3 [dev.garbage] runtime: Concurrent scan code
Routines and logic to preform a concurrent stack scan of go-routines.
This CL excersizes most of the functionality needed. The
major exception being that it does not scan running goroutines.
After doing the scans it relies on a STW to finish the GC, including
rescanning the stacks. It is intended to achieve correctness,
performance will follow.

LGTM=rsc
R=golang-codereviews, rsc
CC=dvyukov, golang-codereviews
https://golang.org/cl/156580043
2014-10-24 11:07:16 -04:00
Rick Hudson
62a4359e2e [dev.garbage] runtime: simplifiy lfstack.c due to undiagnosed buffer corruption.
The changes got rid of the problems we were seeing.
We suspect the pushcnt field has a race.

LGTM=rsc
R=dvyukov, rsc
CC=golang-codereviews
https://golang.org/cl/159330043
2014-10-23 15:51:17 -04:00
Dave Cheney
a08783f078 [dev.power64] runtime: fix SigaltstackT definition for power64le
Also updated defs3_linux.go but had to manually edit defs_linux_power64le.h. Will regenerate the file when cgo is working natively on ppc64.

LGTM=austin
R=rsc, austin
CC=golang-codereviews
https://golang.org/cl/158360043
2014-10-23 08:58:10 +11:00
Austin Clements
a9b9ecc9ef [dev.power64] runtime: fix early GC of Defer objects
go_bootstrap was panicking during runtime initialization
(under runtime.main) because Defer objects were being
prematurely GC'd.  This happened because of an incorrect
change to runtime·unrollgcprog_m to make it endian-agnostic
during the conversion of runtime bitmaps to byte arrays.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/161960044
2014-10-22 16:39:31 -04:00
Austin Clements
f0bd539c59 [dev.power64] all: merge default into dev.power64
This brings dev.power64 up-to-date with the current tip of
default.  go_bootstrap is still panicking with a bad defer
when initializing the runtime (even on amd64).

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/152570049
2014-10-22 15:51:54 -04:00
Austin Clements
977fba763a [dev.power64] runtime: Fix broken merge of noasm.go
The earlier dev.power64 merge missed the port of
runtime/noasm.goc to runtime/noasm_arm.go.  This CL fixes this
by moving noasm_arm.go to noasm.go and adding a +build to
share the file between arm and power64.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/158350043
2014-10-22 14:02:04 -04:00
Austin Clements
2bd616b1a7 build: merge the great pkg/ rename into dev.power64
This also removes pkg/runtime/traceback_lr.c, which was ported
to Go in an earlier commit and then moved to
runtime/traceback.go.

Reviewer: rsc@golang.org
          rsc: LGTM
2014-10-22 13:25:37 -04:00
Dave Cheney
d1b2913710 runtime/cgo: encode BLX directly, fixes one clang build error on arm
Fixes #8348.

Trying to work around clang's dodgy support for .arch by reverting to the external assembler didn't work out so well. Minux had a much better solution to encode the instructions we need as .word directives which avoids .arch altogether.

I've confirmed with gdb that this form produces the expected machine code

Dump of assembler code for function crosscall_arm1:
   0x00000000 <+0>:	push	{r4, r5, r6, r7, r8, r9, r10, r11, r12, lr}
   0x00000004 <+4>:	mov	r4, r0
   0x00000008 <+8>:	mov	r5, r1
   0x0000000c <+12>:	mov	r0, r2
   0x00000010 <+16>:	blx	r5
   0x00000014 <+20>:	blx	r4
   0x00000018 <+24>:	pop	{r4, r5, r6, r7, r8, r9, r10, r11, r12, pc}

There is another compilation failure that blocks building Go with clang on arm

# ../misc/cgo/test
# _/home/dfc/go/misc/cgo/test
/tmp/--407b12.s: Assembler messages:
/tmp/--407b12.s:59: Error: selected processor does not support ARM mode `blx r0'
clang: error: assembler command failed with exit code 1 (use -v to see invocation)
FAIL	_/home/dfc/go/misc/cgo/test [build failed]

I'll open a new issue for that

LGTM=iant
R=iant, minux
CC=golang-codereviews
https://golang.org/cl/158180047
2014-10-22 12:30:15 +11:00
Keith Randall
b60d5e12e9 runtime: warn that cputicks() might not be monotonic.
Get rid of gocputicks(), it is no longer used.

LGTM=bradfitz, dave
R=golang-codereviews, bradfitz, dave, minux
CC=golang-codereviews
https://golang.org/cl/161110044
2014-10-21 14:46:07 -07:00
Keith Randall
3ec8fe45cf runtime: fix flaky TestBlockProfile test
It has been failing periodically on Solaris/x64.
Change blockevent so it always records an event if we called
SetBlockProfileRate(1), even if the time delta is negative or zero.

Hopefully this will fix the test on Solaris.
Caveat: I don't actually know what the Solaris problem is, this
is just an educated guess.

LGTM=dave
R=dvyukov, dave
CC=golang-codereviews
https://golang.org/cl/159150043
2014-10-20 15:48:42 -07:00
David du Colombier
9d06cfc810 runtime: handle non-nil-terminated environment strings on Plan 9
Russ Cox pointed out that environment strings are not
required to be nil-terminated on Plan 9.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/159130044
2014-10-20 23:03:03 +02:00
Keith Randall
e330cc16f4 runtime: dequeue the correct SudoG
select {
       case <- c:
       case <- c:
}

In this case, c.recvq lists two SudoGs which have the same G.
So we can't use the G as the key to dequeue the correct SudoG,
as that key is ambiguous.  Dequeueing the wrong SudoG ends up
freeing a SudoG that is still in c.recvq.

The fix is to use the actual SudoG pointer as the key.

LGTM=dvyukov
R=rsc, bradfitz, dvyukov, khr
CC=austin, golang-codereviews
https://golang.org/cl/159040043
2014-10-18 21:02:49 -07:00
Dmitriy Vyukov
f4de59e234 runtime/pprof: fix memory profiler test
Don't use cmd/pprof as it is not necessary installed
and does not work on nacl and plan9.
Instead just look at the raw profile.

LGTM=crawshaw, rsc
R=golang-codereviews, crawshaw, 0intro, rsc
CC=golang-codereviews
https://golang.org/cl/159010043
2014-10-17 21:28:47 +04:00
Russ Cox
fb173c4185 runtime/pprof: fix test
gogo called from GC is okay
for the same reasons that
gogo called from System or ExternalCode is okay.
All three are fake stack traces.

Fixes #8408.

LGTM=dvyukov, r
R=r, dvyukov
CC=golang-codereviews
https://golang.org/cl/152580043
2014-10-17 11:23:15 -04:00
Russ Cox
58e357ef16 runtime: remove comment that leaked into CL 153710043
This doesn't actually do anything. Maybe it will some day,
but maybe not.

TBR=r
CC=golang-codereviews
https://golang.org/cl/155490043
2014-10-17 11:03:55 -04:00
Russ Cox
1ba977ccca undo CL 159990043 / 421fadcef39a
Dmitriy believes this broke Windows.
It looks like build.golang.org stopped before that,
but it's worth a shot.

««« original CL description
runtime: make pprof a little nicer

Update #8942

This does not fully address issue 8942 but it does make
the profiles much more useful, until that issue can be
fixed completely.

LGTM=dvyukov
R=r, dvyukov
CC=golang-codereviews
https://golang.org/cl/159990043
»»»

TBR=dvyukov
CC=golang-codereviews
https://golang.org/cl/160030043
2014-10-17 10:11:03 -04:00
Russ Cox
aae5c57e38 all: merge default branch into dev.garbage
hg was unable to create a CL on the code review server for this,
so I am submitting the merge by hand.
The only manual edits are in mgc0.c, to reapply the
removal of cached/ncached to the new code.
2014-10-16 15:00:08 -04:00
Russ Cox
25f79b9dbe runtime/pprof: disable new memory test
It cannot run 'go tool pprof'. There is no guarantee that's installed.
It needs to build a temporary pprof binary and run that.
It also needs to skip the test on systems that can't build and
run binaries, namely android and nacl.

See src/cmd/nm/nm_test.go's TestNM for a template.

Update #8867
Status: Accepted

TBR=dvyukov
CC=golang-codereviews
https://golang.org/cl/153710043
2014-10-16 14:58:11 -04:00
Russ Cox
7ed8723d49 runtime: make pprof a little nicer
Update #8942

This does not fully address issue 8942 but it does make
the profiles much more useful, until that issue can be
fixed completely.

LGTM=dvyukov
R=r, dvyukov
CC=golang-codereviews
https://golang.org/cl/159990043
2014-10-16 14:44:55 -04:00
Dmitriy Vyukov
8f47c837fd runtime: fix memory profiler
There are 3 issues:
1. Skip argument of callers is off by 3,
so that all allocations are deep inside of memory profiler.
2. Memory profiling statistics are not updated after runtime.GC.
3. Testing package does not update memory profiling statistics
before capturing the profile.
Also add an end-to-end test.
Fixes #8867.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/148710043
2014-10-16 22:11:26 +04:00
Russ Cox
cb6f5ac0b0 runtime: remove hand-generated ptr bitmaps for reflectcall
A Go prototype can be used instead now, and the compiler
will do a better job than we will doing it by hand.
(We got it wrong in amd64p32, causing the current build
breakage.)

The auto-prototype-matching only applies to functions
without an explicit package path, so the TEXT lines for
reflectcall and callXX are s/runtime·/·/.

LGTM=khr
R=khr
CC=golang-codereviews, iant, r
https://golang.org/cl/153600043
2014-10-15 13:12:16 -04:00
Russ Cox
ff6d0a4df4 cmd/gc, runtime: fix race, nacl for writebarrier changes
The racewalk code was not updated for the new write barriers.
Make it more future-proof.

The new write barrier code assumed that +1 pointer would
be aligned properly for any type that might follow, but that's
not true on 32-bit systems where some types are 64-bit aligned.
The only system like that today is nacl/amd64p32.
Insert a dummy pointer so that the ambiguously typed
value is at +2 pointers, which is always max-aligned.

LGTM=r
R=r
CC=golang-codereviews, iant, khr
https://golang.org/cl/158890046
2014-10-14 23:24:32 -04:00
Alex Brainman
e9ecd4aec5 runtime: handle all windows exception (second attempt)
includes undo of 22318cd31d7d and also:
- always use SetUnhandledExceptionFilter on windows-386;
- crash when receive EXCEPTION_BREAKPOINT in exception handler.

Fixes #8006.

LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews
https://golang.org/cl/155360043
2014-10-15 11:11:11 +11:00
Russ Cox
a3416cf5cd cmd/gc: add 2-, 3-, 4-word write barrier specializations
Assignments of 2-, 3-, and 4-word values were handled
by individual MOV instructions (and for scalars still are).
But if there are pointers involved, those assignments now
go through the write barrier routine. Before this CL, they
went to writebarrierfat, which calls memmove.
Memmove is too much overhead for these small
amounts of data.

Instead, call writebarrierfat{2,3,4}, which are specialized
for the specific amount of data being copied.
Today the write barrier does not care which words are
pointers, so size alone is enough to distinguish the cases.
If we keep these distinctions in Go 1.5 we will need to
expand them for all the pointer-vs-scalar possibilities,
so the current 3 functions will become 3+7+15 = 25,
still not a large burden (we deleted more morestack
functions than that when we dropped segmented stacks).

BenchmarkBinaryTree17           3250972583  3123910344  -3.91%
BenchmarkFannkuch11             3067605223  2964737839  -3.35%
BenchmarkFmtFprintfEmpty        101         96.0        -4.95%
BenchmarkFmtFprintfString       267         235         -11.99%
BenchmarkFmtFprintfInt          261         253         -3.07%
BenchmarkFmtFprintfIntInt       444         402         -9.46%
BenchmarkFmtFprintfPrefixedInt  374         346         -7.49%
BenchmarkFmtFprintfFloat        472         449         -4.87%
BenchmarkFmtManyArgs            1537        1476        -3.97%
BenchmarkGobDecode              13986528    12432985    -11.11%
BenchmarkGobEncode              13120323    12537420    -4.44%
BenchmarkGzip                   451925758   437500578   -3.19%
BenchmarkGunzip                 113267612   110053644   -2.84%
BenchmarkHTTPClientServer       103151      77100       -25.26%
BenchmarkJSONEncode             25002733    23435278    -6.27%
BenchmarkJSONDecode             94213717    82568789    -12.36%
BenchmarkMandelbrot200          4804246     4713070     -1.90%
BenchmarkGoParse                4646114     4379456     -5.74%
BenchmarkRegexpMatchEasy0_32    163         158         -3.07%
BenchmarkRegexpMatchEasy0_1K    433         391         -9.70%
BenchmarkRegexpMatchEasy1_32    154         138         -10.39%
BenchmarkRegexpMatchEasy1_1K    1481        1132        -23.57%
BenchmarkRegexpMatchMedium_32   282         270         -4.26%
BenchmarkRegexpMatchMedium_1K   92421       86149       -6.79%
BenchmarkRegexpMatchHard_32     5209        4718        -9.43%
BenchmarkRegexpMatchHard_1K     158141      147921      -6.46%
BenchmarkRevcomp                699818791   642222464   -8.23%
BenchmarkTemplate               132402383   108269713   -18.23%
BenchmarkTimeParse              509         478         -6.09%
BenchmarkTimeFormat             462         456         -1.30%

LGTM=r
R=r
CC=golang-codereviews
https://golang.org/cl/156200043
2014-10-14 16:31:09 -04:00
Keith Randall
9dc6764d3c runtime: a few optimizations of scanblock.
Lowers gc pause time by 5-10% on test/bench/garbage

LGTM=rsc, dvyukov
R=rsc, dvyukov
CC=golang-codereviews
https://golang.org/cl/157810043
2014-10-14 09:22:47 -07:00
Rick Hudson
0226351d27 [dev.garbage] runtime: Write barrier code.
Comments lay out the concurrent GC algorithms.
This CL implements parts of the algorithm.
The acknowledgement code has been removed from this CL

LGTM=rsc, dvyukov
R=dvyukov, rsc
CC=golang-codereviews
https://golang.org/cl/151540043
2014-10-14 09:51:46 -04:00
Dmitriy Vyukov
f1c0899e6f runtime: add comment to mgc0.h
Missed that comment in CL 153990043.

LGTM=khr
R=khr
CC=golang-codereviews
https://golang.org/cl/156010043
2014-10-09 17:05:38 +04:00
Alex Brainman
64736accdb undo CL 145150043 / 8b3d26697b8d
That was complete failure - builders are broken,
but original cl worked fine on my system.
I will need access to builders
to test this change properly.

««« original CL description
runtime: handle all windows exception

Fixes #8006.

LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews
https://golang.org/cl/145150043
»»»

TBR=rsc
R=golang-codereviews
CC=golang-codereviews
https://golang.org/cl/154180043
2014-10-09 17:24:34 +11:00
Alex Brainman
17a108ba07 runtime: handle all windows exception
Fixes #8006.

LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews
https://golang.org/cl/145150043
2014-10-09 16:52:28 +11:00
Keith Randall
b02450da02 runtime: zero a few more dead pointers.
In channels, zeroing of gp.waiting is missed on a closed channel panic.
m.morebuf.g is not zeroed.

I don't expect the latter causes any problems, but just in case.

LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/151610043
2014-10-08 17:22:34 -07:00
Keith Randall
91e8554b8b runtime: delay freeing of shrunk stacks until gc is done.
This change prevents confusion in the garbage collector.
The collector wants to make sure that every pointer it finds
isn't junk.  Its criteria for junk is (among others) points
to a "free" span.

Because the stack shrinker modifies pointers in the heap,
there is a race condition between the GC scanner and the
shrinker.  The GC scanner can see old pointers (pointers to
freed stacks).  In particular this happens with SudoG.elem
pointers.

Normally this is not a problem, as pointers into stack spans
are ok.  But if the freed stack is the last one in its span,
the span is marked as "free" instead of "contains stacks".

This change makes sure that even if the GC scanner sees
an old pointer, the span into which it points is still
marked as "contains stacks", and thus the GC doesn't
complain about it.

This change will make the GC pause a tiny bit slower, as
the stack freeing now happens in serial with the mark pause.
We could delay the freeing until the mutators start back up,
but this is the simplest change for now.

TBR=dvyukov
CC=golang-codereviews
https://golang.org/cl/158750043
2014-10-08 15:57:20 -07:00
Dmitriy Vyukov
b8fdaaf028 runtime: faster GC scan
The change contains 3 spot optimizations to scan loop:
1. Don't use byte vars, use uintptr's instead.
This seems to alleviate some codegen issue,
and alone accounts to a half of speedup.
2. Remove bitmap cache. Currently we cache only 1 byte,
so caching is not particularly effective anyway.
Removal of the cache simplifies code and positively affects regalloc.
3. Replace BitsMultiword switch with if and
do debug checks only in Debug mode.
I've benchmarked changes separately and ensured that
each of them provides speedup on top of the previous one.
This change as a whole fixes the unintentional regressions
of scan loop that were introduced during development cycle.
Fixes #8625.
Fixes #8565.

On go.benchmarks/garbage benchmark:
GOMAXPROCS=1
time:		-3.13%
cputime:	-3.22%
gc-pause-one:	-15.71%
gc-pause-total:	-15.71%

GOMAXPROCS=32
time:		-1.96%
cputime:	-4.43%
gc-pause-one:	-6.22%
gc-pause-total:	-6.22%

LGTM=khr, rsc
R=golang-codereviews, khr
CC=golang-codereviews, rlh, rsc
https://golang.org/cl/153990043
2014-10-08 13:51:12 +04:00
Russ Cox
94bdf13497 runtime: clear Defer.fn before removing from the G.defer list
Should fix the remaining 'invalid heap pointer' build failures.

TBR=khr
CC=golang-codereviews
https://golang.org/cl/152360043
2014-10-08 00:03:50 -04:00
Russ Cox
f950a14bb5 runtime: fix windows/amd64 build
Out of stack space due to new 2-word call in freedefer.
Go back to smaller function calls.

TBR=brainman
CC=golang-codereviews
https://golang.org/cl/152340043
2014-10-07 23:39:00 -04:00
Russ Cox
2b1659b57d runtime: change Windows M.thread from void* to uintptr
It appears to be an opaque bit pattern more than a pointer.
The Go garbage collector has discovered that for m0
it is set to 0x4c.

Should fix Windows build.

TBR=brainman
CC=golang-codereviews
https://golang.org/cl/149640043
2014-10-07 23:27:25 -04:00
Russ Cox
e6708ee9b1 runtime: clear Defer.panic before removing from G.defer list
Another dangling stack pointer in a cached structure.
Same as SudoG.elem and SudoG.selectdone.

Definitely a fix, and the new test in freedefer makes the
crash reproducible, but probably not a complete fix.
I have seen one dangling pointer in a Defer.panic even
after this fix; I cannot see where it could be coming from.

I think this will fix the solaris build.
I do not think this will fix the occasional failure on the darwin build.

TBR=khr
R=khr
CC=golang-codereviews
https://golang.org/cl/155080043
2014-10-07 23:17:31 -04:00
Keith Randall
dcc4a674d8 runtime: zero pointer-looking scalararg values
I have a CL which at every gc looks through data and bss
sections for nonpointer data (according to gc maps) that
looks like a pointer.  These are potential missing roots.

The only thing it finds are begnign, storing stack pointers
into m0.scalararg[1] and never cleaning them up.  Let's
clean them up now so the test CL passes all.bash cleanly.

The test CL can't be checked in because we might store
pointer-looking things in nonpointer data by accident.

LGTM=iant
R=golang-codereviews, iant, khr
CC=golang-codereviews
https://golang.org/cl/153210043
2014-10-07 15:21:00 -07:00
Keith Randall
6ea3746adf runtime: update heap dump format for 1.4
We no longer have full type information in the heap, so
we can't dump that any more.  Instead we dump ptr/noptr
maps so at least we can compute graph connectivity.

In addition, we still dump Iface/Eface types so together
with dwarf type info we might be able to reconstruct
types of most things in the heap.

LGTM=dvyukov
R=golang-codereviews, dvyukov, rsc, khr
CC=golang-codereviews
https://golang.org/cl/155940043
2014-10-07 13:36:16 -07:00
Russ Cox
685204747d runtime: fix _cgo_allocate(0)
Fixes a SWIG bug reported off-list.

LGTM=iant
R=iant
CC=golang-codereviews
https://golang.org/cl/155990043
2014-10-07 16:27:40 -04:00
Russ Cox
11e53e46a6 runtime: crash if we see an invalid pointer into GC arena
This will help find bugs during the release freeze.
It's not clear it should be kept for the release itself.
That's issue 8861.

The most likely thing that would trigger this is stale
pointers that previously were ignored or caused memory
leaks. These were allowed due to the use of conservative
collection. Now that everything is precise, we should not
see them anymore.

The small number check reinforces what the stack copier
is already doing, catching the storage of integers in pointers.
It caught issue 8864.

The check is disabled if _cgo_allocate is linked into the binary,
which is to say if the binary is using SWIG to allocate untyped
Go memory. In that case, there are invalid pointers and there's
nothing we can do about it.

LGTM=rlh
R=golang-codereviews, dvyukov, rlh
CC=golang-codereviews, iant, khr, r
https://golang.org/cl/148470043
2014-10-07 11:07:18 -04:00
Russ Cox
18172c42ff runtime: remove type-punning for Type.gc[0], gc[1]
Depending on flags&KindGCProg,
gc[0] and gc[1] are either pointers or inlined bitmap bits.
That's not compatible with a precise garbage collector:
it needs to be always pointers or never pointers.

Change the inlined bitmap case to store a pointer to an
out-of-line bitmap in gc[0]. The out-of-line bitmaps are
dedup'ed, so that for example all pointer types share the
same out-of-line bitmap.

Fixes #8864.

LGTM=r
R=golang-codereviews, dvyukov, r
CC=golang-codereviews, iant, khr, rlh
https://golang.org/cl/155820043
2014-10-07 11:06:51 -04:00
Russ Cox
42e67170f4 [dev.garbage] all: merge default into dev.garbage
This picks up the TestDualStackUDPListener fix.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/147660044
2014-10-06 14:45:36 -04:00
Russ Cox
9ba99011fa [dev.garbage] all: merge default into dev.garbage
This picks up the selectdone dangling pointer fix, among others.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/153070045
2014-10-06 14:18:56 -04:00
Russ Cox
9a5b055b95 runtime: update docs, code for SetFinalizer
At last minute before 1.3 we relaxed SetFinalizer to avoid
crashes when you pass the result of a global alloc to it.
This avoids the crash but makes SetFinalizer a bit too relaxed.

Document that the finalizer of a global allocation may not run.

Tighten the SetFinalizer check to ignore a global allocation but
not ignore everything else.

Fixes #7656.

LGTM=r, iant
R=golang-codereviews, iant, r
CC=dvyukov, golang-codereviews, khr, rlh
https://golang.org/cl/145930043
2014-10-06 14:18:09 -04:00
Russ Cox
13da360845 runtime: clear sg.selectdone before saving in SudoG cache
Removes another dangling pointer that might
cause a memory leak in 1.4 or crash the GC in 1.5.

LGTM=rlh
R=golang-codereviews
CC=golang-codereviews, iant, khr, r, rlh
https://golang.org/cl/150520043
2014-10-03 15:33:29 -04:00
Russ Cox
0120f8378d runtime: clear stale values from G.param and SudoG.elem
This change was necessary on the dev.garbage branch
to keep the garbage collector from seeing pointers into
invalid heap areas.

On this default (Go 1.4) branch, the change removes
some possibility for memory leaks.

LGTM=khr
R=golang-codereviews, khr
CC=golang-codereviews, iant, r, rlh
https://golang.org/cl/155760043
2014-10-03 13:36:48 -04:00
Russ Cox
3ffd29fb2c cmd/cc, runtime: disallow structs without tags
Structs without tags have no unique name to use in the
Go definitions generated from the C types.
This caused issue 8812, fixed by CL 149260043.
Avoid future problems by requiring struct tags.

Update runtime as needed.
(There is no other C code in the tree.)

LGTM=bradfitz, iant
R=golang-codereviews, bradfitz, dave, iant
CC=golang-codereviews, khr, r
https://golang.org/cl/150360043
2014-10-03 12:44:20 -04:00
Russ Cox
904ec00981 [dev.garbage] merge default into dev.garbage 2014-10-03 12:22:19 -04:00
Rick Hudson
d42328c9f7 [dev.garbage] runtime: scan and mark phase refactoring
Refactoring of the scan and mark phase so that concurrent GC,
in particular the write barrier, can share a common infrastructure.
Now that the scan and mark phases have been separated
we will be able to scan stacks without blackening any objects.
This in turn will allow us to delay installing expensive write barrier code.

LGTM=rsc
R=rsc, khr, dvyukov
CC=golang-codereviews
https://golang.org/cl/145640044
2014-10-03 11:33:57 -04:00
Russ Cox
a3630c9e44 [dev.garbage] runtime: make sure G.param and SudoG.elem do not hold stale pointers
In old conservative Go, this could cause memory leaks.
A new pickier collector might reasonably crash when it saw one of these.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/147480043
2014-10-02 16:49:11 -04:00
Russ Cox
fdb0cc6e7b [dev.garbage] runtime: remove another BitsMultiWord
Not found because it was not used by name.
Add name in comments for what's left behind.

LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/148430043
2014-10-02 14:26:04 -04:00
Brad Fitzpatrick
85cdc49e8a os, syscall: add Unsetenv
Also address a TODO, making Clearenv pass through to cgo.

Based largely on Minux's earlier https://golang.org/cl/82040044

Fixes #6423

LGTM=iant, alex.brainman, r, rsc
R=rsc, iant, r, alex.brainman
CC=golang-codereviews
https://golang.org/cl/148370043
2014-10-01 11:17:15 -07:00
Keith Randall
ac9218f5f0 runtime: fix scanning of gc work buffer
GC types were not being generated for the garbage collector
work buffer.  The markfor object was being collected as a result.
This broke amd64p32 and maybe plan9 builds.  Why it didn't break
every build I'm not sure...

Fixes #8812

LGTM=0intro, rsc
R=golang-codereviews, dave, khr, 0intro, rsc
CC=golang-codereviews
https://golang.org/cl/149260043
2014-09-30 08:51:02 -07:00
Dmitriy Vyukov
12308d5a0b runtime: fix throwsplit check
Newstack runs on g0, g0->throwsplit is never set.

LGTM=rsc
R=rsc
CC=golang-codereviews, khr
https://golang.org/cl/147370043
2014-09-30 19:34:33 +04:00
Keith Randall
70b2da98ca runtime: initialize traceback variables earlier
Our traceback code needs to know the PC of several special
functions, including goexit, mcall, etc.  Make sure that
these PCs are initialized before any traceback occurs.

Fixes #8766

LGTM=rsc
R=golang-codereviews, rsc, khr, bradfitz
CC=golang-codereviews
https://golang.org/cl/145570043
2014-09-29 21:21:36 -07:00
Dave Cheney
0b36211cfb liblink: generate MRC replacement in liblink, not tls_arm
Fixes #8690.

This CL moves the save of LR around BL runtime.read_tls_fallback to liblink as it is not needed when MRC is not replaced.

LGTM=rsc, minux
R=rsc, khr, minux
CC=golang-codereviews
https://golang.org/cl/147310043
2014-09-30 10:03:10 +10:00
Keith Randall
b4380a3ba2 runtime: delete unused variables.
We're not comparing with code addresses any more.  Instead,
we use nil algorithm functions to mark uncomparable types.

LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/151040044
2014-09-29 14:05:33 -07:00
Keith Randall
e1364a6d0e runtime: fix cgo_topofstack to save clobbered registers
Fixes #8816

At least, I hope it does.

TBR=rsc
CC=golang-codereviews
https://golang.org/cl/153730043
2014-09-28 23:52:08 -07:00
Keith Randall
1aa65fe8d4 runtime: add load_g call in arm callback.
Need to restore the g register.  Somehow this line vaporized from
CL 144130043.  Also cgo_topofstack -> _cgo_topofstack, that vaporized also.

TBR=rsc
CC=golang-codereviews
https://golang.org/cl/150940044
2014-09-25 08:37:04 -07:00
Keith Randall
1b6807bb06 cgo: adjust return value location to account for stack copies.
During a cgo call, the stack can be copied.  This copy invalidates
the pointer that cgo has into the return value area.  To fix this
problem, pass the address of the location containing the stack
top value (which is in the G struct).  For cgo functions which
return values, read the stktop before and after the cgo call to
compute the adjustment necessary to write the return value.

Fixes #8771

LGTM=iant, rsc
R=iant, rsc, khr
CC=golang-codereviews
https://golang.org/cl/144130043
2014-09-25 07:59:01 -07:00
Russ Cox
3c94b1d305 runtime: more NOPTR
Fixes linux builds (_vdso); may fix others.
I can at least cross-compile cmd/go for every
implemented system now.

TBR=iant
CC=golang-codereviews
https://golang.org/cl/142630043
2014-09-24 19:04:06 -04:00
Russ Cox
75cca0526d runtime: more NOPTR
Fixes (or makes better) various builds.

TBR=iant
CC=golang-codereviews
https://golang.org/cl/146280043
2014-09-24 17:50:44 -04:00