On Plan 9, there's no "kill all threads" system call, so exit is done
by sending a "go: exit" note to each OS process. If concurrent GC
occurs during this loop, deadlock sometimes results. Prevent this by
incrementing m.locks before sending notes.
Change-Id: I31aa15134ff6e42d9a82f9f8a308620b3ad1b1b1
Reviewed-on: https://go-review.googlesource.com/20477
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Alternative to golang.org/cl/19852. This memory layout doesn't have
an easy type representation, but it is noticeably smaller than the
current funcType, and saves significant extra space.
Some notes on the layout are in reflect/type.go:
// A *rtype for each in and out parameter is stored in an array that
// directly follows the funcType (and possibly its uncommonType). So
// a function type with one method, one input, and one output is:
//
// struct {
// funcType
// uncommonType
// [2]*rtype // [0] is in, [1] is out
// uncommonTypeSliceContents
// }
There are three arbitrary limits introduced by this CL:
1. No more than 65535 function input parameters.
2. No more than 32767 function output parameters.
3. reflect.FuncOf is limited to 128 parameters.
I don't think these are limits in practice, but are worth noting.
Reduces godoc binary size by 2.4%, 330KB.
For #6853.
Change-Id: I225c0a0516ebdbe92d41dfdf43f716da42dfe347
Reviewed-on: https://go-review.googlesource.com/19916
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Instead of a pointer on every rtype, use a bit flag to indicate that
the contents of uncommonType directly follows the rtype value when it
is needed.
This requires a bit of juggling in the compiler's rtype encoder. The
backing arrays for fields in the rtype are presently encoded directly
after the slice header. This packing requires separating the encoding
of the uncommonType slice headers from their backing arrays.
Reduces binary size of godoc by ~180KB (1.5%).
No measurable change in all.bash time.
For #6853.
Change-Id: I60205948ceb5c0abba76fdf619652da9c465a597
Reviewed-on: https://go-review.googlesource.com/19790
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Before, those C files might have been intended for the Plan 9 C compiler,
but that option was removed in Go 1.5. We can simplify the maintenance
of cgo packages now if we assume C files (and C++ and M and SWIG files)
should only be considered when cgo is enabled.
Also remove newly unnecessary build tags in runtime/cgo's C files.
Fixes#14123
Change-Id: Ia5a7fe62b9469965aa7c3547fe43c6c9292b8205
Reviewed-on: https://go-review.googlesource.com/19613
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently work.finalizersDone is reset only at the beginning of
gcStart. As a result, it will be set when checkmark runs, so checkmark
will skip scanning finalizers. Hence, if there are any bugs that cause
the regular scan of finalizers to miss pointers, checkmark will also
miss them and fail to detect the missed pointer.
Fix this by resetting finalizersDone in gcResetMarkState. This way it
gets reset before any full mark, which is exactly what we want.
Change-Id: I4ddb5eba5b3b97e52aaf3e08fd9aa692bda32b20
Reviewed-on: https://go-review.googlesource.com/20332
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Rick Hudson <rlh@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Implementation more or less follows plan9_386 version.
Revised 7 March to correct a bug in runtime.seek and
tidy whitespace for 8-column tabs.
Change-Id: I2e921558b5816502e8aafe330530c5a48a6c7537
Reviewed-on: https://go-review.googlesource.com/18966
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Plan 9 trap/signal handling differs on ARM from other architectures
because ARM has a link register. Also trap message syntax varies
between different architectures (historical accident?).
Revised 7 March to clarify a comment.
Change-Id: Ib6485f82857a2f9a0d6b2c375cf0aaa230b83656
Reviewed-on: https://go-review.googlesource.com/18969
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
We used to start background mark workers and assists at different
times, so we needed to keep track of these separately. They're now set
to exactly the same time, so clean things up by merging them in to one
value, markStartTime.
Change-Id: I17c9843c3ed2d6f07b4c8cd0b2c438fc6de23b53
Reviewed-on: https://go-review.googlesource.com/20143
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
Current runtime.WriteHeapProfile() doesn't print correct
EnableGC. Even if GOGC=off, the result file has below line:
# EnableGC = true
It is hard to print correct status of the variable because of corner
cases e.g. initialization. For avoiding confusion, this commit removes
the print.
Change-Id: Ia792454a6c650bdc50a06fbaff4df7b6330ae08a
Reviewed-on: https://go-review.googlesource.com/18600
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
gcMarkRootCheck takes ~10ns per goroutine. This is just a debugging
check, so disable it (plus, if something is going to go wrong, it's
more likely to go wrong during concurrent mark).
We may be able to re-enable this later, or move it to after we've
started the world again. (But not for 1.6.x.)
For 1.6.x.
Fixes#14419.
name / 95%ile-time/markTerm old new delta
500kIdleGs-12 24.0ms ± 0% 18.9ms ± 6% -21.46% (p=0.000 n=15+20)
Change-Id: Idb2a2b1771449de772c159ef95920d6df1090666
Reviewed-on: https://go-review.googlesource.com/20148
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently we reset the mark state during STW sweep termination. This
involves looping over all of the goroutines. Each iteration of this
loop takes ~25ns, so at around 400k goroutines, we'll exceed our 10ms
pause goal.
However, it's safe to do this before we stop the world for sweep
termination because nothing is consuming this state yet. Hence, move
the reset to just before STW.
This isn't perfect: a long reset can still delay allocating goroutines
that block on GC starting. But it's certainly better to block some
things eventually than to block everything immediately.
For 1.6.x.
Fixes#14420.
name \ 95%ile-time/sweepTerm old new delta
500kIdleGs-12 11312µs ± 6% 18.9µs ± 6% -99.83% (p=0.000 n=16+20)
Change-Id: I9815c4d8d9b0d3c3e94dfdab78049cefe0dcc93c
Reviewed-on: https://go-review.googlesource.com/20147
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Also fix compiler-invoked panics to avoid a confusing "malloc deadlock"
crash if they are invoked while executing the runtime.
Fixes#14599.
Change-Id: I89436abcbf3587901909abbdca1973301654a76e
Reviewed-on: https://go-review.googlesource.com/20219
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
go test github.com/onsi/gomega/gbytes now passes at tip, and tests
added to the reflect package.
Fixes#14645
Change-Id: I16216c1a86211a1103d913237fe6bca5000cf885
Reviewed-on: https://go-review.googlesource.com/20221
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This change consolidates functions and methods related to TCPAddr,
TCPConn and TCPListener for maintenance purpose, especially for
documentation. Also refactors Dial error code paths.
The followup changes will update comments and examples.
Updates #10624.
Change-Id: I3333ee218ebcd08928f9e2826cd1984d15ea153e
Reviewed-on: https://go-review.googlesource.com/20009
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The tree's pretty inconsistent about single space vs double space
after a period in documentation. Make it consistently a single space,
per earlier decisions. This means contributors won't be confused by
misleading precedence.
This CL doesn't use go/doc to parse. It only addresses // comments.
It was generated with:
$ perl -i -npe 's,^(\s*// .+[a-z]\.) +([A-Z]),$1 $2,' $(git grep -l -E '^\s*//(.+\.) +([A-Z])')
$ go test go/doc -update
Change-Id: Iccdb99c37c797ef1f804a94b22ba5ee4b500c4f7
Reviewed-on: https://go-review.googlesource.com/20022
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dave Day <djd@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is a subset of https://golang.org/cl/20022 with only the copyright
header lines, so the next CL will be smaller and more reviewable.
Go policy has been single space after periods in comments for some time.
The copyright header template at:
https://golang.org/doc/contribute.html#copyright
also uses a single space.
Make them all consistent.
Change-Id: Icc26c6b8495c3820da6b171ca96a74701b4a01b0
Reviewed-on: https://go-review.googlesource.com/20111
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Avoid targeting a partial register with load;
ensure source of load (writebarrier) is aligned.
Better yet would be "CMPB $1,writebarrier" but that requires
wrestling with flagalloc (mem operand complicates moving
instruction around).
Didn't see a change in time for
benchcmd -n 10 Build go build net/http
Verified that we clean the code up properly:
0x20a8 <main.main+104>: mov 0xc30a2(%rip),%eax
# 0xc5150 <runtime.writeBarrier>
0x20ae <main.main+110>: test %al,%al
Change-Id: Id5fb8c260eaec27bd727cb0ae1476c60343b0986
Reviewed-on: https://go-review.googlesource.com/19998
Reviewed-by: Keith Randall <khr@golang.org>
Commit a5c3bbe modified adjustpointers to use *uintptrs instead of
*unsafe.Pointers for manipulating stack pointers for clarity and to
eliminate the unnecessary write barrier when writing the updated stack
pointer.
This commit makes the equivalent change to adjustpointer.
Change-Id: I6dc309590b298bdd86ecdc9737db848d6786c3f7
Reviewed-on: https://go-review.googlesource.com/17148
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently dropg does not unwire locked g/m.
This is unnecessary distiction between locked and non-locked g/m.
We always restart goroutines with execute which re-wires g/m.
First, this produces false sense that this distinction is necessary.
Second, it can confuse some sanity and cross checks. For example,
if we check that g/m are unwired before we wire them in execute,
the check will fail for locked g/m. I've hit this while doing some
race detector changes, When we deschedule a goroutine and run
scheduler code, m.curg is generally nil, but not for locked ms.
Remove the distinction.
Change-Id: I3b87a28ff343baa1d564aab1f821b582a84dee07
Reviewed-on: https://go-review.googlesource.com/19950
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
REP-prefixed instructions have a large startup cost.
Avoid them like the plague.
benchmark old ns/op new ns/op delta
BenchmarkIndexByte10-8 22.4 5.34 -76.16%
Fixes#13983
Change-Id: I857e956e240fc9681d053f2584ccf24c1b272bb3
Reviewed-on: https://go-review.googlesource.com/18703
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
_Genqueue and _Gscanenqueue were introduced as part of the GC quiesce
code. The quiesce code was removed by 197aa9e, but these states and
some associated code stuck around. Remove them.
Change-Id: I69df81881602d4a431556513dac2959668d27c20
Reviewed-on: https://go-review.googlesource.com/19638
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently most uses of gcWork use the per-P gcWork, but there are two
places that still use a stack-based gcWork. Simplify things by making
these instead use the per-P gcWork.
Change-Id: I712d012cce9dd5757c8541824e9641ac1c2a329c
Reviewed-on: https://go-review.googlesource.com/19636
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently markroot uses a gcWork on the stack and disposes of it
immediately after marking one root. This used to be necessary because
markroot was called from the depths of parfor, but now that we call it
directly and have ready access to a gcWork at the call site, pass the
gcWork in, use it directly in markroot, and share it across calls to
markroot from the same P.
Change-Id: Id7c3b811bfb944153760e01873c07c8d18909be1
Reviewed-on: https://go-review.googlesource.com/19635
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
When gcWork was first introduced, the compiler's escape analysis
wasn't good enough to detect that that method receiver didn't escape,
so we had to hack around this.
Now that the compiler can figure out this for itself, remove these
hacks.
Change-Id: I9f73fab721e272410b8b6905b564e7abc03c0dfe
Reviewed-on: https://go-review.googlesource.com/19634
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The channel code must not allow stack splits between when it assigns a
potential stack pointer to sudog.elem (or sudog.selectdone) and when
it makes the sudog visible to copystack by putting it on the g.waiting
list. We do get this right everywhere, but add a comment about this
subtlety for future eyes.
Change-Id: I941da150437167acff37b0e56983c793f40fcf79
Reviewed-on: https://go-review.googlesource.com/19632
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently the heapBitsSweepSpan comment claims that heapBitsSweepSpan
sets the heap bitmap for the first two words to dead. In fact, it sets
the first *four* words to scalar/dead. This is important because first
two words don't actually have a dead bit, so for objects larger than
two words it *must* set a dead bit in third word to reset the object
to a "noscan" state. For example, we use this in heapBits.hasPointers
to detect that an object larger than two words is noscan.
Change-Id: Ie166a628bed5060851db083475c7377adb349d6c
Reviewed-on: https://go-review.googlesource.com/19630
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Our stack frame sizes look pretty good now. Lower the stack
guard from 1024 to 720.
Tip is currently using 720.
We could go lower (to 640 at least) except PPC doesn't like that.
Change-Id: Ie5f96c0e822435638223f1e8a2bd1a1eed68e6aa
Reviewed-on: https://go-review.googlesource.com/19922
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
This indirectly implements a small fix for runtime/pprof: it used to
look for runtime.gopanic when it should have been looking for
runtime.sigpanic.
Update #11432.
Change-Id: I5e3f5203b2ac5463efd85adf6636e64174aacb1d
Reviewed-on: https://go-review.googlesource.com/19869
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Simplifies some code as ptrToThis was unreliable under dynamic
linking. Now the same type lookup is used regardless of execution
mode.
A synthetic relocation, R_USETYPE, is introduced to make sure the
linker includes *T on use of T, if *T is carrying methods.
Changes the heap dump format. Anything reading the format needs to
look at the last bool of a type of an interface value to determine
if the type should be the pointer-to type.
Reduces binary size of cmd/go by 0.2%.
For #6853.
Change-Id: I79fcb19a97402bdb0193f3c7f6d94ddf061ee7b2
Reviewed-on: https://go-review.googlesource.com/19695
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Like bionic, musl also doesn't provide vsyscall helper in %gs:0x10,
and as int $0x80 is as fast as calling %gs:0x10, just use int $0x80
always.
Because we're no longer using vsyscall in VDSO, get rid of VDSO code
for linux/386 too.
Fixes#14476.
Change-Id: I00ec8652060700e0a3c9b524bfe3c16a810263f6
Reviewed-on: https://go-review.googlesource.com/19833
Run-TryBot: Minux Ma <minux@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Bump up the multiplier to 20. Also run the fast version first, so that
the slow version is likely to start up faster.
Change-Id: Ia0654cc1212ab03a45da1904d3e4b57d6a8d02a0
Reviewed-on: https://go-review.googlesource.com/19835
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
They do the same thing, except memequal also has the short-circuit
check if the two pointers are equal.
A) We might as well always do the short-circuit check, it is only 2 instructions.
B) The extra function call (memequal->memeq) is expensive.
benchmark old ns/op new ns/op delta
BenchmarkArrayEqual-8 8.56 5.31 -37.97%
No noticeable affect on the former memeq user (maps).
Fixes#14302
Change-Id: I85d1ada59ed11e64dd6c54667f79d32cc5f81948
Reviewed-on: https://go-review.googlesource.com/19843
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Richard Miller
David Crawshaw
Russ Cox
Burcu Dogan
Austin Clements
Matthew Dempsky
Hitoshi Mitake
Ian Lance Taylor
Mikio Hara
Brad Fitzpatrick
Keith Randall
Gerrit Code Review
David Chase
Dmitry Vyukov
Martin Möhrmann
Shenghou Ma
Shawn Smith