Sysmon thread parks if no goroutines are running (runtime.sched.npidle == runtime.gomaxprocs).
Currently it's unparked when a goroutine enters syscall, it was enough
to retake P's from blocking syscalls.
But it's not enough for reliable goroutine preemption. We need to ensure that
sysmon runs if any goroutines are running.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12167043

I don't know why the memstats code is flaky.

TBR=bradfitz
CC=golang-dev
https://golang.org/cl/12160043

Fixes #5668.

R=golang-dev, rsc, r
CC=golang-dev
https://golang.org/cl/12001056

Fixes #5730.

R=dsymonds, r, kamil.kisiel
CC=golang-dev
https://golang.org/cl/11998044

Adds layout cases with seconds for stdISO8601 and stdNumTZ with and without colons. Update time.Format to append seconds for those cases.

Fixes #4934.

R=golang-dev, r, bradfitz
CC=golang-dev
https://golang.org/cl/8132044

Generated by addca.

R=gobot
CC=golang-dev
https://golang.org/cl/12146043

This means that printing a Node will produce output that can be used as valid input.
It won't be exactly the same - some spacing may be different - but it will mean the same.

Fixes #4593.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/12006047

When scanning input and "white space" is permitted, a carriage return
followed immediately by a newline (\r\n) is treated exactly the same
as a plain newline (\n). I hope this makes it work better on Windows.

We do it everywhere, not just on Windows, since why not?

Fixes #5391.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/12142043

When comparing strings, check these (in order):
- length mismatch => not equal
- string pointer equal => equal
- if length is short:
  - memeq on body
- if length is long:
  - compare first&last few bytes, if different => not equal
  - save entry as a possible match
  - after checking every entry, if there is only one possible
    match, use memeq on that entry.  Otherwise, fallback to hash.

benchmark                 old ns/op    new ns/op    delta
BenchmarkSameLengthMap           43            4  -89.77%

Fixes #5194.
Update #3885.

R=golang-dev, bradfitz, khr, rsc
CC=golang-dev
https://golang.org/cl/12128044

The prefix was not uniformly applied and is probably better left off anyway.

Fixes #4944.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/12140043

Fixes #5730.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/12141043

R=golang-dev, dave
CC=golang-dev
https://golang.org/cl/12090043

This is what I get for being talked into a test.

TBR=bradfitz
CC=golang-dev
https://golang.org/cl/12045044

Was stupidly float64; should be complex128.
The tests still pass.

Fixes #5649.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12107044

Fixes one build failure.

R=golang-dev, dave
CC=golang-dev
https://golang.org/cl/12139043

There is a chance that the SIGQUIT will make the test process
dump its stacks as part of exiting, which would be nice for
finding out what it is doing.

Right now the builders are occasionally timing out running
the runtime test. I hope this will give us some information
about the state of the runtime.

R=golang-dev, dave
CC=golang-dev
https://golang.org/cl/12041051

struct Hmap is the header for a map value.

CL 8377046 made flags a uint32 so that it could be updated atomically,
but that bumped the struct to 56 bytes, which allocates as 64 bytes (on amd64).

hash0 is initialized from runtime.fastrand1, which returns a uint32,
so the top 32 bits were always zero anyway. Declare it as a uint32
to reclaim 4 bytes and bring the Hmap size back down to a 48-byte allocation.

Fixes #5237.

R=golang-dev, khr, khr
CC=bradfitz, dvyukov, golang-dev
https://golang.org/cl/12034047

Fixes #5460.

R=golang-dev, rsc, bradfitz
CC=golang-dev
https://golang.org/cl/12123043

Fixes #5972.

R=golang-dev, adonovan
CC=golang-dev
https://golang.org/cl/12125043

This is mainly to force another build
with goroutine preemption.

R=rsc
CC=golang-dev
https://golang.org/cl/12006045

All known issues with preemption have beed fixed.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12008044

Do not run Syscall benchmarks under race detector,
they split stack in syscall status.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12093045

If netFD is closed by finalizer, runtime netpoll descriptor is not freed.

R=golang-dev, dave, alex.brainman
CC=golang-dev
https://golang.org/cl/12037043

Fixes #5598.

R=ken2
CC=golang-dev
https://golang.org/cl/12104043

Not just the first one.

Fixes #5433.
Fixes #5913.

R=ken2
CC=golang-dev
https://golang.org/cl/12028049

R=golang-dev, dave
CC=golang-dev
https://golang.org/cl/12091043

R=golang-dev, dave
CC=golang-dev
https://golang.org/cl/12082045

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/12050045

EscapeText now escapes 0xFFFD returned from DecodeRune as 0xFFFD, rather than passing through the original byte.
Fixes #5880.

R=golang-dev, r, bradfitz, adg
CC=golang-dev
https://golang.org/cl/11975043

Generated by addca.

R=gobot
CC=golang-dev
https://golang.org/cl/12084043

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/11990043

Fixes #2648.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/11331043

R=adonovan
CC=golang-dev
https://golang.org/cl/12072043

As promised.

TBR=dvyukov
CC=golang-dev
https://golang.org/cl/12063043

R=adonovan
CC=golang-dev
https://golang.org/cl/12062043

I want to see the timing information in build logs,
and we can't see the logs for "ok" builds.
So make the build fail everywhere.

Will roll back immediately.

TBR=dvyukov
CC=golang-dev
https://golang.org/cl/12058046

R=dvyukov
CC=golang-dev
https://golang.org/cl/12028046

Document endian-ness assumption.

R=dvyukov
CC=golang-dev
https://golang.org/cl/12056044

The current failure is:
fatal error: runtime: stack split during syscall
goroutine 2 [stack split]:
_si2v(0xb6ebaebc, 0x3b9aca00)
        /usr/local/go/src/pkg/runtime/vlrt_arm.c:628 fp=0xb6ebae9c
runtime.timediv(0xf8475800, 0xd, 0x3b9aca00, 0xb6ebaef4)
        /usr/local/go/src/pkg/runtime/runtime.c:424 +0x1c fp=0xb6ebaed4

Just adding textflag 7 causes the following error:
notetsleep: nosplit stack overflow
        128	assumed on entry to notetsleep
        96	after notetsleep uses 32
        60	after runtime.futexsleep uses 36
        4	after runtime.timediv uses 56
        -4	after _si2v uses 8

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12001045

R=adonovan, r
CC=golang-dev
https://golang.org/cl/11961043