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31484 Commits

Author SHA1 Message Date
Ian Lance Taylor
0fe62e7575 os: skip TestPipeThreads on Plan 9
It can't work since Plan 9 does not support the runtime poller.

Fixes build.

Change-Id: I9ec33eb66019d9364c6ff6519b61b32e59498559
Reviewed-on: https://go-review.googlesource.com/37091
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-15 21:27:12 +00:00
Russ Cox
1f77db94f8 runtime: do not call wakep from enlistWorker, to avoid possible deadlock
We have seen one instance of a production job suddenly spinning to
100% CPU and becoming unresponsive. In that one instance, a SIGQUIT
was sent after 328 minutes of spinning, and the stacks showed a single
goroutine in "IO wait (scan)" state.

Looking for things that might get stuck if a goroutine got stuck in
scanning a stack, we found that injectglist does:

	lock(&sched.lock)
	var n int
	for n = 0; glist != nil; n++ {
		gp := glist
		glist = gp.schedlink.ptr()
		casgstatus(gp, _Gwaiting, _Grunnable)
		globrunqput(gp)
	}
	unlock(&sched.lock)

and that casgstatus spins on gp.atomicstatus until the _Gscan bit goes
away. Essentially, this code locks sched.lock and then while holding
sched.lock, waits to lock gp.atomicstatus.

The code that is doing the scan is:

	if castogscanstatus(gp, s, s|_Gscan) {
		if !gp.gcscandone {
			scanstack(gp, gcw)
			gp.gcscandone = true
		}
		restartg(gp)
		break loop
	}

More analysis showed that scanstack can, in a rare case, end up
calling back into code that acquires sched.lock. For example:

	runtime.scanstack at proc.go:866
	calls runtime.gentraceback at mgcmark.go:842
	calls runtime.scanstack$1 at traceback.go:378
	calls runtime.scanframeworker at mgcmark.go:819
	calls runtime.scanblock at mgcmark.go:904
	calls runtime.greyobject at mgcmark.go:1221
	calls (*runtime.gcWork).put at mgcmark.go:1412
	calls (*runtime.gcControllerState).enlistWorker at mgcwork.go:127
	calls runtime.wakep at mgc.go:632
	calls runtime.startm at proc.go:1779
	acquires runtime.sched.lock at proc.go:1675

This path was found with an automated deadlock-detecting tool.
There are many such paths but they all go through enlistWorker -> wakep.

The evidence strongly suggests that one of these paths is what caused
the deadlock we observed. We're running those jobs with
GOTRACEBACK=crash now to try to get more information if it happens
again.

Further refinement and analysis shows that if we drop the wakep call
from enlistWorker, the remaining few deadlock cycles found by the tool
are all false positives caused by not understanding the effect of calls
to func variables.

The enlistWorker -> wakep call was intended only as a performance
optimization, it rarely executes, and if it does execute at just the
wrong time it can (and plausibly did) cause the deadlock we saw.

Comment it out, to avoid the potential deadlock.

Fixes #19112.
Unfixes #14179.

Change-Id: I6f7e10b890b991c11e79fab7aeefaf70b5d5a07b
Reviewed-on: https://go-review.googlesource.com/37093
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-02-15 21:22:36 +00:00
Hana Kim
8833af3f4b runtime/pprof: print newly added fields of runtime.MemStats
in heap profile with debug mode

Change-Id: I3a80d03a4aa556614626067a8fd698b3b00f4290
Reviewed-on: https://go-review.googlesource.com/36962
Reviewed-by: Austin Clements <austin@google.com>
2017-02-15 21:14:37 +00:00
Heschi Kreinick
35a95df571 cmd/compile/internal/ssa: display NamedValues in SSA html output.
Change-Id: If268b42b32e6bcd6e7913bffa6e493dc78af40aa
Reviewed-on: https://go-review.googlesource.com/36539
TryBot-Result: Gobot Gobot <gobot@golang.org>
Run-TryBot: Heschi Kreinick <heschi@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-15 21:11:57 +00:00
Lynn Boger
2ac32b6360 cmd/go: improve stale reason for packages
This adds more information to the pkg stale reason for debugging
purposes.

Change-Id: I7b626db4520baa1127195ae859f4da9b49304636
Reviewed-on: https://go-review.googlesource.com/36944
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-15 21:02:28 +00:00
Ian Lance Taylor
c05b06a12d os: use poller for file I/O
This changes the os package to use the runtime poller for file I/O
where possible. When a system call blocks on a pollable descriptor,
the goroutine will be blocked on the poller but the thread will be
released to run other goroutines. When using a non-pollable
descriptor, the os package will continue to use thread-blocking system
calls as before.

For example, on GNU/Linux, the runtime poller uses epoll. epoll does
not support ordinary disk files, so they will continue to use blocking
I/O as before. The poller will be used for pipes.

Since this means that the poller is used for many more programs, this
modifies the runtime to only block waiting for the poller if there is
some goroutine that is waiting on the poller. Otherwise, there is no
point, as the poller will never make any goroutine ready. This
preserves the runtime's current simple deadlock detection.

This seems to crash FreeBSD systems, so it is disabled on FreeBSD.
This is issue 19093.

Using the poller on Windows requires opening the file with
FILE_FLAG_OVERLAPPED. We should only do that if we can remove that
flag if the program calls the Fd method. This is issue 19098.

Update #6817.
Update #7903.
Update #15021.
Update #18507.
Update #19093.
Update #19098.

Change-Id: Ia5197dcefa7c6fbcca97d19a6f8621b2abcbb1fe
Reviewed-on: https://go-review.googlesource.com/36800
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-02-15 19:31:55 +00:00
Dave Cheney
81ec3f6a6c internal/poll: remove unused poll.pollDesc methods
Change-Id: Ic2b20c8238ff0ca5513d32e54ef2945fa4d0c3d2
Reviewed-on: https://go-review.googlesource.com/37033
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-02-15 18:39:43 +00:00
Marcel van Lohuizen
79fab70a63 testing: fix stats bug for sub benchmarks
Fixes golang/go#18815.

Change-Id: Ic9d5cb640a555c58baedd597ed4ca5dd9f275c97
Reviewed-on: https://go-review.googlesource.com/36990
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-02-15 09:26:33 +00:00
Robert Griesemer
d390283ff4 cmd/compile/internal/syntax: compiler directives must start at beginning of line
- ignore them, if they don't.
- added tests

Fixes #18393.

Change-Id: I13f87b81ac6b9138ab5031bb3dd6bebc4c548156
Reviewed-on: https://go-review.googlesource.com/37020
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-15 06:49:21 +00:00
Alex Brainman
a8dc43edd1 internal/testenv: do not delete target file
We did not create it. We should not delete it.

Change-Id: If98454ab233ce25367e11a7c68d31b49074537dd
Reviewed-on: https://go-review.googlesource.com/37030
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-15 06:03:15 +00:00
Robert Griesemer
2770c507a5 cmd/compile: fix position for "missing type in composite literal" error
Fixes #18231.

Change-Id: If1615da4db0e6f0516369a1dc37340d80c78f237
Reviewed-on: https://go-review.googlesource.com/37018
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-15 01:33:44 +00:00
Robert Griesemer
5267ac2732 cmd/compile/internal/syntax: establish principled position information
Until now, the parser set the position for each Node to the position of
the first token belonging to that node. For compatibility with the now
defunct gc parser, in many places that position information was modified
when the gcCompat flag was set (which it was, by default). Furthermore,
in some places, position information was not set at all.

This change removes the gcCompat flag and all associated code, and sets
position information for all nodes in a more principled way, as proposed
by mdempsky (see #16943 for details). Specifically, the position of a
node may not be at the very beginning of the respective production. For
instance for an Operation `a + b`, the position associated with the node
is the position of the `+`. Thus, for `a + b + c` we now get different
positions for the two additions.

This change does not pass toolstash -cmp because position information
recorded in export data and pcline tables is different. There are no
other functional changes.

Added test suite testing the position of all nodes.

Fixes #16943.

Change-Id: I3fc02bf096bc3b3d7d2fa655dfd4714a1a0eb90c
Reviewed-on: https://go-review.googlesource.com/37017
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-15 01:33:03 +00:00
Daniel Martí
6910756f9b math/big: simplify bool expression
Change-Id: I280c53be455f2fe0474ad577c0f7b7908a4eccb2
Reviewed-on: https://go-review.googlesource.com/36993
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-14 23:34:25 +00:00
Russ Cox
72aa757ddd encoding/xml: fix incorrect indirect code in chardata, comment, innerxml fields
The new tests in this CL have been checked against Go 1.7 as well
and all pass in Go 1.7, with the one exception noted in a comment
(an intentional change to omitempty already present before this CL).

CL 15684 made the intentional change to omitempty.
This CL fixes bugs introduced along the way.

Most of these are corner cases that are arguably not that important,
but they've always worked all the way back to Go 1, and someone
cared enough to file #19063. The most significant problem found
while adding tests is that in the case of a nil *string field with
`xml:",chardata"`, the existing code silently stops processing not just
that field but the entire remainder of the struct.
Even if #19063 were not worth fixing, this chardata bug would be.

Fixes #19063.

Change-Id: I318cf8f9945e1a4615982d9904e109fde577ebf9
Reviewed-on: https://go-review.googlesource.com/36954
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-14 23:23:40 +00:00
Bryan C. Mills
eebd8f51e8 mime: add benchmarks for TypeByExtension and ExtensionsByType
These are possible use-cases for sync.Map.

Updates golang/go#18177

Change-Id: I5e2a3d1249967c37d3f89a41122bf4a90522db11
Reviewed-on: https://go-review.googlesource.com/36964
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-02-14 23:02:07 +00:00
Kirill Smelkov
4477fd097f cmd/compile/internal/ssa: combine 2 byte loads + shifts into word load + rolw 8 on AMD64
... and same for stores. This does for binary.BigEndian.Uint16() what
was already done for Uint32 and Uint64 with BSWAP in 10f75748 (CL 32222).

Here is how generated code changes e.g. for the following function
(omitting saying the same prologue/epilogue):

	func get16(b [2]byte) uint16 {
		return binary.BigEndian.Uint16(b[:])
	}

"".get16 t=1 size=21 args=0x10 locals=0x0

	// before
        0x0000 00000 (x.go:15)  MOVBLZX "".b+9(FP), AX
        0x0005 00005 (x.go:15)  MOVBLZX "".b+8(FP), CX
        0x000a 00010 (x.go:15)  SHLL    $8, CX
        0x000d 00013 (x.go:15)  ORL     CX, AX

	// after
	0x0000 00000 (x.go:15)	MOVWLZX	"".b+8(FP), AX
	0x0005 00005 (x.go:15)	ROLW	$8, AX

encoding/binary is speedup overall a bit:

name                    old time/op    new time/op    delta
ReadSlice1000Int32s-4     4.83µs ± 0%    4.83µs ± 0%     ~     (p=0.206 n=4+5)
ReadStruct-4              1.29µs ± 2%    1.28µs ± 1%   -1.27%  (p=0.032 n=4+5)
ReadInts-4                 384ns ± 1%     385ns ± 1%     ~     (p=0.968 n=4+5)
WriteInts-4                534ns ± 3%     526ns ± 0%   -1.54%  (p=0.048 n=4+5)
WriteSlice1000Int32s-4    5.02µs ± 0%    5.11µs ± 3%     ~     (p=0.175 n=4+5)
PutUint16-4               0.59ns ± 0%    0.49ns ± 2%  -16.95%  (p=0.016 n=4+5)
PutUint32-4               0.52ns ± 0%    0.52ns ± 0%     ~     (all equal)
PutUint64-4               0.53ns ± 0%    0.53ns ± 0%     ~     (all equal)
PutUvarint32-4            19.9ns ± 0%    19.9ns ± 1%     ~     (p=0.556 n=4+5)
PutUvarint64-4            54.5ns ± 1%    54.2ns ± 0%     ~     (p=0.333 n=4+5)

name                    old speed      new speed      delta
ReadSlice1000Int32s-4    829MB/s ± 0%   828MB/s ± 0%     ~     (p=0.190 n=4+5)
ReadStruct-4            58.0MB/s ± 2%  58.7MB/s ± 1%   +1.30%  (p=0.032 n=4+5)
ReadInts-4              78.0MB/s ± 1%  77.8MB/s ± 1%     ~     (p=0.968 n=4+5)
WriteInts-4             56.1MB/s ± 3%  57.0MB/s ± 0%     ~     (p=0.063 n=4+5)
WriteSlice1000Int32s-4   797MB/s ± 0%   783MB/s ± 3%     ~     (p=0.190 n=4+5)
PutUint16-4             3.37GB/s ± 0%  4.07GB/s ± 2%  +20.83%  (p=0.016 n=4+5)
PutUint32-4             7.73GB/s ± 0%  7.72GB/s ± 0%     ~     (p=0.556 n=4+5)
PutUint64-4             15.1GB/s ± 0%  15.1GB/s ± 0%     ~     (p=0.905 n=4+5)
PutUvarint32-4           201MB/s ± 0%   201MB/s ± 0%     ~     (p=0.905 n=4+5)
PutUvarint64-4           147MB/s ± 1%   147MB/s ± 0%     ~     (p=0.286 n=4+5)

( "a bit" only because most of the time is spent in reflection-like things
  there, not actual bytes decoding. Even for direct PutUint16 benchmark the
  looping adds overhead and lowers visible benefit. For code-generated encoders /
  decoders actual effect is more than 20% )

Adding Uint32 and Uint64 raw benchmarks too for completeness.

NOTE I had to adjust load-combining rule for bswap case to match first 2 bytes
loads as result of "2-bytes load+shift" -> "loadw + rorw 8" rewrite. Reason is:
for loads+shift, even e.g. into uint16 var

	var b []byte
	var v uin16
	v = uint16(b[1]) | uint16(b[0])<<8

the compiler eventually generates L(ong) shift - SHLLconst [8], probably
because it is more straightforward / other reasons to work on the whole
register. This way 2 bytes rewriting rule is using SHLLconst (not SHLWconst) in
its pattern, and then it always gets matched first, even if 2-byte rule comes
syntactically after 4-byte rule in AMD64.rules because 4-bytes rule seemingly
needs more applyRewrite() cycles to trigger. If 2-bytes rule gets matched for
inner half of

	var b []byte
	var v uin32
	v = uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24

and we keep 4-byte load rule unchanged, the result will be MOVW + RORW $8 and
then series of byte loads and shifts - not one MOVL + BSWAPL.

There is no such problem for stores: there compiler, since it probably knows
store destination is 2 bytes wide, uses SHRWconst 8 (not SHRLconst 8) and thus
2-byte store rule is not a subset of rule for 4-byte stores.

Fixes #17151  (int16 was last missing piece there)

Change-Id: Idc03ba965bfce2b94fef456b02ff6742194748f6
Reviewed-on: https://go-review.googlesource.com/34636
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-14 22:17:08 +00:00
Bryan C. Mills
7ffdb75775 expvar: add benchmarks for steady-state Map Add calls
Add a benchmark for setting a String value, which we may
want to treat differently from Int or Float due to the need to support
Add methods for the latter.

Update tests to use only the exported API instead of making (fragile)
assumptions about unexported fields.

The existing Map benchmarks construct a new Map for each iteration, which
focuses the benchmark results on the initial allocation costs for the
Map and its entries. This change adds variants of the benchmarks which
use a long-lived map in order to measure steady-state performance for
Map updates on existing keys.

Updates #18177

Change-Id: I62c920991d17d5898c592446af382cd5c04c528a
Reviewed-on: https://go-review.googlesource.com/36959
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-02-14 22:11:35 +00:00
Michael Munday
d2fea0447f math/big: fix s390x test build tags
The tests failed to compile when using the math_big_pure_go tag on
s390x.

Change-Id: I2a09f53ff6562ab9bc9b886cffc0f6205bbfcfbb
Reviewed-on: https://go-review.googlesource.com/36956
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-14 19:44:35 +00:00
Cherry Zhang
78200799a2 cmd/compile: undo special handling of zero-valued STRUCTLIT
CL 35261 introduces special handling of zero-valued STRUCTLIT for
efficient struct zeroing. But it didn't cover all use cases, for
example, CONVNOP STRUCTLIT is not handled.

On the other hand, CL 34566 handles zeroing earlier, so we don't
need the change in CL 35261 for efficient zeroing. Other uses of
zero-valued struct literals are very rare. So undo the change in
walk.go in CL 35261.

Add a test for efficient zeroing.

Fixes #19084.

Change-Id: I0807f7423fb44d47bf325b3c1ce9611a14953853
Reviewed-on: https://go-review.googlesource.com/36955
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2017-02-14 18:57:56 +00:00
Kirill Smelkov
bd91e3569a cmd/compile/internal/ssa: generate bswap/store for indexed bigendian byte stores too on AMD64
Commit 10f75748 (CL 32222) added rewrite rules to combine byte loads/stores +
shifts into larger loads/stores + bswap. For loads both MOVBload and
MOVBloadidx1 were handled but for store only MOVBstore was there without
MOVBstoreidx added to rewrite pattern. Fix it.

Here is how generated code changes for the following 2 functions
(ommitting staying the same prologue/epilogue):

    func put32(b []byte, i int, v uint32) {
            binary.BigEndian.PutUint32(b[i:], v)
    }

    func put64(b []byte, i int, v uint64) {
            binary.BigEndian.PutUint64(b[i:], v)
    }

"".put32 t=1 size=100 args=0x28 locals=0x0

	// before
	0x0032 00050 (x.go:5)	MOVL	CX, DX
	0x0034 00052 (x.go:5)	SHRL	$24, CX
	0x0037 00055 (x.go:5)	MOVQ	"".b+8(FP), BX
	0x003c 00060 (x.go:5)	MOVB	CL, (BX)(AX*1)
	0x003f 00063 (x.go:5)	MOVL	DX, CX
	0x0041 00065 (x.go:5)	SHRL	$16, DX
	0x0044 00068 (x.go:5)	MOVB	DL, 1(BX)(AX*1)
	0x0048 00072 (x.go:5)	MOVL	CX, DX
	0x004a 00074 (x.go:5)	SHRL	$8, CX
	0x004d 00077 (x.go:5)	MOVB	CL, 2(BX)(AX*1)
	0x0051 00081 (x.go:5)	MOVB	DL, 3(BX)(AX*1)

	// after
	0x0032 00050 (x.go:5)	BSWAPL	CX
	0x0034 00052 (x.go:5)	MOVQ	"".b+8(FP), DX
	0x0039 00057 (x.go:5)	MOVL	CX, (DX)(AX*1)

"".put64 t=1 size=155 args=0x28 locals=0x0

	// before
	0x0037 00055 (x.go:9)	MOVQ	CX, DX
	0x003a 00058 (x.go:9)	SHRQ	$56, CX
	0x003e 00062 (x.go:9)	MOVQ	"".b+8(FP), BX
	0x0043 00067 (x.go:9)	MOVB	CL, (BX)(AX*1)
	0x0046 00070 (x.go:9)	MOVQ	DX, CX
	0x0049 00073 (x.go:9)	SHRQ	$48, DX
	0x004d 00077 (x.go:9)	MOVB	DL, 1(BX)(AX*1)
	0x0051 00081 (x.go:9)	MOVQ	CX, DX
	0x0054 00084 (x.go:9)	SHRQ	$40, CX
	0x0058 00088 (x.go:9)	MOVB	CL, 2(BX)(AX*1)
	0x005c 00092 (x.go:9)	MOVQ	DX, CX
	0x005f 00095 (x.go:9)	SHRQ	$32, DX
	0x0063 00099 (x.go:9)	MOVB	DL, 3(BX)(AX*1)
	0x0067 00103 (x.go:9)	MOVQ	CX, DX
	0x006a 00106 (x.go:9)	SHRQ	$24, CX
	0x006e 00110 (x.go:9)	MOVB	CL, 4(BX)(AX*1)
	0x0072 00114 (x.go:9)	MOVQ	DX, CX
	0x0075 00117 (x.go:9)	SHRQ	$16, DX
	0x0079 00121 (x.go:9)	MOVB	DL, 5(BX)(AX*1)
	0x007d 00125 (x.go:9)	MOVQ	CX, DX
	0x0080 00128 (x.go:9)	SHRQ	$8, CX
	0x0084 00132 (x.go:9)	MOVB	CL, 6(BX)(AX*1)
	0x0088 00136 (x.go:9)	MOVB	DL, 7(BX)(AX*1)

	// after
	0x0033 00051 (x.go:9)	BSWAPQ	CX
	0x0036 00054 (x.go:9)	MOVQ	"".b+8(FP), DX
	0x003b 00059 (x.go:9)	MOVQ	CX, (DX)(AX*1)

Updates #17151

Change-Id: I3f4a7f28f210e62e153e60da5abd1d39508cc6c4
Reviewed-on: https://go-review.googlesource.com/34635
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
2017-02-14 18:35:43 +00:00
Kale Blankenship
a0645fcaf9 net/http: document ErrServerClosed
Fixes #19085

Change-Id: Ib11b9a22ea8092aca9e1c9c36b1fb015dd555c4b
Reviewed-on: https://go-review.googlesource.com/36943
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-14 16:36:23 +00:00
Austin Clements
0993b2fd06 runtime: remove g.stackAlloc
Since we're no longer stealing space for the stack barrier array from
the stack allocation, the stack allocation is simply
g.stack.hi-g.stack.lo.

Updates #17503.

Change-Id: Id9b450ae12c3df9ec59cfc4365481a0a16b7c601
Reviewed-on: https://go-review.googlesource.com/36621
Run-TryBot: Austin Clements <austin@google.com>
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2017-02-14 15:52:56 +00:00
Austin Clements
d089a6c718 runtime: remove stack barriers
Now that we don't rescan stacks, stack barriers are unnecessary. This
removes all of the code and structures supporting them as well as
tests that were specifically for stack barriers.

Updates #17503.

Change-Id: Ia29221730e0f2bbe7beab4fa757f31a032d9690c
Reviewed-on: https://go-review.googlesource.com/36620
Run-TryBot: Austin Clements <austin@google.com>
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-14 15:52:54 +00:00
Austin Clements
c5ebcd2c8a runtime: remove rescan list
With the hybrid barrier, rescanning stacks is no longer necessary so
the rescan list is no longer necessary. Remove it.

This leaves the gcrescanstacks GODEBUG variable, since it's useful for
debugging, but changes it to simply walk all of the Gs to rescan
stacks rather than using the rescan list.

We could also remove g.gcscanvalid, which is effectively a distributed
rescan list. However, it's still useful for gcrescanstacks mode and it
adds little complexity, so we'll leave it in.

Fixes #17099.
Updates #17503.

Change-Id: I776d43f0729567335ef1bfd145b75c74de2cc7a9
Reviewed-on: https://go-review.googlesource.com/36619
Run-TryBot: Austin Clements <austin@google.com>
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Reviewed-by: Rick Hudson <rlh@golang.org>
2017-02-14 15:52:51 +00:00
Austin Clements
7aeb915d6b runtime: remove unused debug.wbshadow
The wbshadow implementation was removed a year and a half ago in
1635ab7dfe, but the GODEBUG setting remained. Remove the GODEBUG
setting since it doesn't do anything.

Change-Id: I19cde324a79472aff60acb5cc9f7d4aa86c0c0ed
Reviewed-on: https://go-review.googlesource.com/36618
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
2017-02-14 15:52:49 +00:00
Nathan Caza
a610957f2e net/http: handle absolute paths in mapDirOpenError
The current implementation does not account for Dir being
initialized with an absolute path on systems that start
paths with filepath.Separator. In this scenario, the
original error is returned, and not checked for file
segments.

This change adds a test for this case, and corrects the
behavior by ignoring blank path segments in the loop.

Refs #18984

Change-Id: I9b79fd0a73a46976c8e2feda0283ef0bb2b62ea1
Reviewed-on: https://go-review.googlesource.com/36804
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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2017-02-14 04:41:36 +00:00
Josh Bleecher Snyder
ef30a1c8aa runtime: fix some assembly offset names
For vet. There are more. This is a start.

Change-Id: Ibbbb2b20b5db60ee3fac4a1b5913d18fab01f6b9
Reviewed-on: https://go-review.googlesource.com/36939
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
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2017-02-14 02:09:48 +00:00
Josh Bleecher Snyder
785cb7e098 all: fix some printf format strings
Appease vet.

Change-Id: Ie88de08b91041990c0eaf2e15628cdb98d40c660
Reviewed-on: https://go-review.googlesource.com/36938
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
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2017-02-14 02:09:30 +00:00
Josh Bleecher Snyder
cc2a52adef all: use keyed composite literals
Makes vet happy.

Change-Id: I7250f283c96e82b9796c5672a0a143ba7568fa63
Reviewed-on: https://go-review.googlesource.com/36937
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
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2017-02-14 02:09:14 +00:00
Dave Cheney
c0165a38fd internal/poll: only build str.go on plan9
Alternatively the contents of str.go could be moved into fd_io_plan9.go

Change-Id: I9d7ec85bbb376f4244eeca732f25c0b77cadc6a6
Reviewed-on: https://go-review.googlesource.com/36971
Run-TryBot: Dave Cheney <dave@cheney.net>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
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2017-02-14 02:02:39 +00:00
Dave Cheney
84cf1f050d internal/poll: remove named return values and naked returns
Change-Id: I283f4453e5cf8b22995b3abffccae182cfbb6945
Reviewed-on: https://go-review.googlesource.com/36970
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Dave Cheney <dave@cheney.net>
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2017-02-14 01:48:46 +00:00
Caleb Spare
45356c1a08 time: add Duration.Truncate and Duration.Round
Fixes #18996

Change-Id: I0b0f7270960b368ce97ad4456f60bcc1fc2a8313
Reviewed-on: https://go-review.googlesource.com/36615
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Reviewed-by: Russ Cox <rsc@golang.org>
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2017-02-14 00:40:31 +00:00
Josh Bleecher Snyder
46a75870ad runtime: speed up fastrand() % n
This occurs a fair amount in the runtime for non-power-of-two n.
Use an alternative, faster formulation.

name           old time/op  new time/op  delta
Fastrandn/2-8  4.45ns ± 2%  2.09ns ± 3%  -53.12%  (p=0.000 n=14+14)
Fastrandn/3-8  4.78ns ±11%  2.06ns ± 2%  -56.94%  (p=0.000 n=15+15)
Fastrandn/4-8  4.76ns ± 9%  1.99ns ± 3%  -58.28%  (p=0.000 n=15+13)
Fastrandn/5-8  4.96ns ±13%  2.03ns ± 6%  -59.14%  (p=0.000 n=15+15)

name                    old time/op  new time/op  delta
SelectUncontended-8     33.7ns ± 2%  33.9ns ± 2%  +0.70%  (p=0.000 n=49+50)
SelectSyncContended-8   1.68µs ± 4%  1.65µs ± 4%  -1.54%  (p=0.000 n=50+45)
SelectAsyncContended-8   282ns ± 1%   277ns ± 1%  -1.50%  (p=0.000 n=48+43)
SelectNonblock-8        5.31ns ± 1%  5.32ns ± 1%    ~     (p=0.275 n=45+44)
SelectProdCons-8         585ns ± 3%   577ns ± 2%  -1.35%  (p=0.000 n=50+50)
GoroutineSelect-8       1.59ms ± 2%  1.59ms ± 1%    ~     (p=0.084 n=49+48)

Updates #16213

Change-Id: Ib555a4d7da2042a25c3976f76a436b536487d5b7
Reviewed-on: https://go-review.googlesource.com/36932
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
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2017-02-14 00:01:22 +00:00
Ian Lance Taylor
83c58ac710 internal/poll: return error if WriteConsole fails
Fixes #19068.

Change-Id: Id76037826376b5fe8b588fe3dc02182dfaff8c21
Reviewed-on: https://go-review.googlesource.com/36935
Run-TryBot: Ian Lance Taylor <iant@golang.org>
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-13 23:49:48 +00:00
Ian Lance Taylor
62237c2c8e runtime: if runtime is stale while testing, show StaleReason
Update #19062.

Change-Id: I7397b573389145b56e73d2150ce0fc9aa75b3caa
Reviewed-on: https://go-review.googlesource.com/36934
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
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2017-02-13 23:46:12 +00:00
Robert Griesemer
efb3cab960 cmd/compile/internal/syntax: generalize error about var decls in init clauses
Change-Id: I62f9748b97bec245338ebf9686fbf6ad6dc6a9c2
Reviewed-on: https://go-review.googlesource.com/36931
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-13 23:15:32 +00:00
Robert Griesemer
f823d30514 cmd/compile/internal/syntax: better error for malformed 'if' statements
Use distinction between explicit and automatically inserted semicolons
to provide a better error message if the condition in an 'if' statement
is missing.

For #18747.

Change-Id: Iac167ae4e5ad53d2dc73f746b4dee9912434bb59
Reviewed-on: https://go-review.googlesource.com/36930
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-13 22:02:36 +00:00
Matthew Dempsky
02de5ed748 cmd/internal/obj: add AddrName type and cleanup AddrType values
Passes toolstash -cmp.

Change-Id: Ida3eda9bd9d79a34c1c3f18cb41aea9392698076
Reviewed-on: https://go-review.googlesource.com/36950
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
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2017-02-13 21:56:17 +00:00
Kirill Smelkov
e2948f7efe cmd/compile: Show arch/os when something in TestAssembly fails
It is not always obvious from the first glance when looking at
TestAssembly failure in which context the code was generated. For
example x86 and x86-64 are similar, and those of us who do not work with
assembly every day can even take s390x version as something similar to x86.

So when something fails lets print the whole test context - this
includes os and arch which were previously missing. An example failure:

before:

--- FAIL: TestAssembly (40.48s)
        asm_test.go:46: expected:       MOVWZ   \(.*\),
                go:
                import "encoding/binary"
                func f(b []byte) uint32 {
                        return binary.LittleEndian.Uint32(b)
                }

                asm:"".f t=1 size=160 args=0x20 locals=0x0
		...

after:

--- FAIL: TestAssembly (40.43s)
        asm_test.go:46: linux/s390x: expected:  MOVWZ   \(.*\),
                go:
                import "encoding/binary"
                func f(b []byte) uint32 {
                        return binary.LittleEndian.Uint32(b)
                }

                asm:"".f t=1 size=160 args=0x20 locals=0x0

Motivated-by: #18946#issuecomment-279491071

Change-Id: I61089ceec05da7a165718a7d69dec4227dd0e993
Reviewed-on: https://go-review.googlesource.com/36881
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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2017-02-13 20:30:31 +00:00
Sameer Ajmani
8d7722ede2 cmd/go: add "syscall" to the set of packages that run extFiles++
This eliminates the need for syscall/asm.s, which is now empty.

Change-Id: Ied060195e03e9653251f54ea8ef6572444b37fdf
Reviewed-on: https://go-review.googlesource.com/36844
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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2017-02-13 20:28:02 +00:00
Sokolov Yura
663226d8e1 runtime: make fastrand to generate 32bit values
Extend period of fastrand from (1<<31)-1 to (1<<32)-1 by
choosing other polynom and reacting on high bit before shift.

Polynomial is taken at https://users.ece.cmu.edu/~koopman/lfsr/index.html
from 32.dat.gz . It is referred as F7711115 cause this list of
polynomials is for LFSR with shift to right (and fastrand uses shift to
left). (old polynomial is referred in 31.dat.gz as 7BB88888).

There were couple of places with conversation of fastrand to int, which
leads to negative values on 32bit platforms. They are fixed.

Change-Id: Ibee518a3f9103e0aea220ada494b3aec77babb72
Reviewed-on: https://go-review.googlesource.com/36875
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-02-13 20:22:02 +00:00
Sameer Ajmani
15c62e8535 net/http: document Response.Header values that are subordinate to other fields
I noticed that Content-Length may appear in http.Response.Header, but the docs
say it should be omitted.  Per discussion with bradfitz@, updating the docs to
indicate that the struct fields are authoritative.

Change-Id: Id1807ff9d4ba5de425d8b147205f29b18351230f
Reviewed-on: https://go-review.googlesource.com/36842
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-13 20:10:19 +00:00
Michael Munday
074b73b1b2 cmd/compile: fix s390x load-combining rules
MOVD{reg,nop} operations (added in CL 36256) inserted to preserve
type information were blocking the load-combining rules. Fix this
by merging type changes into loads wherever possible.

Fixes #19059.

Change-Id: I8a1df06eb0f231b40ae43107d4a3bd0b9c441b59
Reviewed-on: https://go-review.googlesource.com/36843
Run-TryBot: Michael Munday <munday@ca.ibm.com>
Reviewed-by: Keith Randall <khr@golang.org>
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2017-02-13 20:04:14 +00:00
Ian Lance Taylor
40c27ed5bc runtime: if runtime is stale while testing, show cmd/go output
Update #19062.

Change-Id: If6a4c4f8d12e148b162256f13a8ee423f6e30637
Reviewed-on: https://go-review.googlesource.com/36918
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-13 20:00:05 +00:00
Sameer Ajmani
5a303aa1e9 syscall: delete the "use" function and calls in non-generated files.
Delete use stub from asm.s, leaving only a dummy file.
Deleting the file causes Windows build to fail.

Fixes #16607

Change-Id: Ic5a55e042e588f1e1bc6605a3d309d1eabdeb288
Reviewed-on: https://go-review.googlesource.com/36716
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-13 19:58:05 +00:00
Chris Manghane
e9bb9e597e cmd/go: respect group sticky bit on install.
When installing a package to a different directory using `go build`,
`mv` cannot be used if the destination directory has the group sticky
bit set.  Instead, `cp` should be used to make sure the destination
file has the correct permissions.

Fixes golang/go#18878.

Change-Id: I5423f559e7f84df080ed47816e19a22c6d00ab6d
Reviewed-on: https://go-review.googlesource.com/36797
Run-TryBot: Chris Manghane <cmang@golang.org>
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Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-02-13 19:33:36 +00:00
Ian Lance Taylor
4e0f63940c net: use internal/poll for DragonFly setKeepAlivePeriod
Fixes DragonFly build.

Change-Id: Id6b439cd4023ea8e3ed7cd9b70eec553c9eee4be
Reviewed-on: https://go-review.googlesource.com/36916
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2017-02-13 19:25:12 +00:00
Ian Lance Taylor
fc13da1648 internal/poll: only export FD.eofError for testing on posix systems
Fixes build on plan9.

Change-Id: Idbb1e6887c24a873de77c92095198847ed953278
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2017-02-13 19:10:50 +00:00
Daniel Theophanes
50ab37d008 database/sql: convert test timeouts to explicit waits with checks
When testing context cancelation behavior do not rely on context
timeouts. Use explicit checks in all such tests. In closeDB
convert the simple check for zero open conns with a wait loop
for zero open conns.

Fixes #19024
Fixes #19041

Change-Id: Iecfcc4467e91249fceb21ffd1f7c62c58140d8e9
Reviewed-on: https://go-review.googlesource.com/36902
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2017-02-13 19:05:28 +00:00
Ian Lance Taylor
3792db5183 net: refactor poller into new internal/poll package
This will make it possible to use the poller with the os package.

This is a lot of code movement but the behavior is intended to be
unchanged.

Update #6817.
Update #7903.
Update #15021.
Update #18507.

Change-Id: I1413685928017c32df5654ded73a2643820977ae
Reviewed-on: https://go-review.googlesource.com/36799
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-02-13 18:36:28 +00:00