Russ Cox [Fri, 10 Feb 2017 19:45:41 +0000 (14:45 -0500)]
runtime: use two-level list for semaphore address search in semaRoot
If there are many goroutines contending for two different locks
and both locks hash to the same semaRoot, the scans to find the
goroutines for a particular lock can end up being O(n), making
n lock acquisitions quadratic.
As long as only one actively-used lock hashes to each semaRoot
there's no problem, since the list operations in that case are O(1).
But when the second actively-used lock hits the same semaRoot,
then scans for entries with for a given lock have to scan over the
entries for the other lock.
Fix this problem by changing the semaRoot to hold only one sudog
per unique address. In the running example, this drops the length of
that list from O(n) to 2. Then attach other goroutines waiting on the
same address to a separate list headed by the sudog in the semaRoot list.
Those "same address list" operations are still O(1), so now the
example from above works much better.
There is still an assumption here that in real programs you don't have
many many goroutines queueing up on many many distinct addresses.
If we end up with that problem, we can replace the top-level list with
a treap.
Fixes #17953.
Change-Id: I78c5b1a5053845275ab31686038aa4f6db5720b2
Reviewed-on: https://go-review.googlesource.com/36792
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Cezar Sa Espinola [Thu, 8 Dec 2016 00:45:06 +0000 (22:45 -0200)]
image/png: reduce memory allocs encoding images by reusing buffers
This change allows greatly reducing memory allocations with a slightly
performance improvement as well.
Instances of (*png).Encoder can have a optional BufferPool attached to
them. This allows reusing temporary buffers used when encoding a new
image. This buffers include instances to zlib.Writer and bufio.Writer.
Also, buffers for current and previous rows are saved in the encoder
instance and reused as long as their cap() is enough to fit the current
image row.
A new benchmark was added to demonstrate the performance improvement
when setting a BufferPool to an Encoder instance:
When code defines a method on T,
the compiler generates a corresponding wrapper method on *T.
The first thing the wrapper does is check whether
the pointer is nil and if so, call panicwrap.
This is done to provide a useful error message.
The existing implementation gets its information
from arguments set up by the compiler.
However, with some trouble, this information can
be extracted from the name of the wrapper method itself.
Removing the arguments to panicwrap simplifies and
shrinks the wrapper method.
It also means that the call to panicwrap does not
require any stack space.
This enables a further optimization on amd64/x86,
which is to skip the function prologue if nothing
else in the method requires stack space.
This is frequently the case in simple, hot methods,
such as Less and Swap in sort.Interface implementations.
Dhananjay Nakrani [Sat, 24 Dec 2016 06:28:45 +0000 (22:28 -0800)]
cmd/compile: Ensure left-to-right assignment
Add temporaries to reorder the assignment for OAS2XXX nodes.
This makes orderstmt(), rewrite
a, b, c = ...
as
tmp1, tmp2, tmp3 = ...
a, b, c = tmp1, tmp2, tmp3
and
a, ok = ...
as
t1, t2 = ...
a = t1
ok = t2
Paul Jolly [Fri, 9 Dec 2016 11:15:23 +0000 (11:15 +0000)]
doc: improve issue template and contribution guidelines
Encourage people towards the various help forums as a first port of
call. Better sign-posting will reduce the incidence or questions being
asked in the issue tracker that should otherwise be handled elsewhere,
thereby keeping the issue tracker email traffic more focussed.
Alberto Donizetti [Sat, 11 Feb 2017 19:06:54 +0000 (20:06 +0100)]
strings: make parameters names less confusing
Using 'sep' as parameter name for strings functions that take a
separator argument is fine, but for functions like Index or Count that
look for a substring it's better to use 'substr' (like Contains
already does).
Remi Gillig [Sat, 11 Feb 2017 17:34:48 +0000 (17:34 +0000)]
path/filepath: fix TestWinSplitListTestsAreValid on some systems
The environment variables used in those tests override the default
OS ones. However, one of them (SystemRoot) seems to be required on
some Windows systems for invoking cmd.exe properly.
Change-Id: Ia2852666ef44e7ef0bba2360e92caccc83fd0e5c
Reviewed-on: https://go-review.googlesource.com/36796 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
testing: only call ReadMemStats if necessary when benchmarking
When running benchmarks with -cpuprofile,
the entire process gets profiled,
and ReadMemStats is surprisingly expensive.
Running the sort benchmarks right now with
-cpuprofile shows almost half of all execution
time in ReadMemStats.
Since ReadMemStats is not required if the benchmark
does not need allocation stats, simply skip it.
This will make cpu profiles nicer to read
and significantly speed up the process of running benchmarks.
It might also make sense to toggle cpu profiling
on/off as we begin/end individual benchmarks,
but that wouldn't get us the time savings of
skipping ReadMemStats, so this CL is useful in itself.
Change-Id: I425197b1ee11be4bc91d22b929e2caf648ebd7c5
Reviewed-on: https://go-review.googlesource.com/36791
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Nigel Tao [Fri, 10 Feb 2017 03:04:59 +0000 (14:04 +1100)]
image/color: tweak the YCbCr to RGBA conversion formula again.
The 0x10101 magic constant is a little more principled than 0x10100, as
the rounding adjustment now spans the complete range [0, 0xffff] instead
of [0, 0xff00].
Due to rounding errors both ways, we often but not always get a perfect
round trip (where r0 == r1 && g0 == g1 && b0 == b1). This is true both
before and after this commit. In some cases we got luckier, in others we
got unluckier.
For example, before this commit, (180, 135, 164) doesn't round trip
perfectly (it's off by 1) but (180, 135, 165) does. After this commit,
both cases are reversed: the former does and the latter doesn't (again
off by 1). Over all possible (r, g, b) triples, there doesn't seem to be
a big change for better or worse.
There is some history in these CLs:
image/color: tweak the YCbCr to RGBA conversion formula.
https://go-review.googlesource.com/#/c/12220/2/src/image/color/ycbcr.go
image/color: have YCbCr.RGBA work in 16-bit color, per the Color
interface.
https://go-review.googlesource.com/#/c/8073/2/src/image/color/ycbcr.go
Change-Id: Ib25ba7039f49feab2a9d1a4141b86db17db7b3e1
Reviewed-on: https://go-review.googlesource.com/36732
Run-TryBot: Nigel Tao <nigeltao@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Rob Pike <r@golang.org>
Mark Adams [Fri, 3 Feb 2017 14:46:25 +0000 (08:46 -0600)]
cmd/go: use Bitbucket v2 REST API when determining VCS
The existing implementation uses v1.0 of Bitbucket's REST API. The newer
version 2.0 of Bitbucket's REST API provides the same information but
with support for partial responses allowing the client to request only
the response fields that are relevant to their usage of the API
resulting in a much smaller payload size.
The partial response functionality in the Bitbucket API is documented here:
https://developer.atlassian.com/bitbucket/api/2/reference/meta/partial-response
The v2.0 of the Bitbucket repositories API is documented here:
https://developer.atlassian.com/bitbucket/api/2/reference/resource/repositories/%7Busername%7D/%7Brepo_slug%7D#get
Brad Fitzpatrick [Tue, 6 Dec 2016 19:55:10 +0000 (19:55 +0000)]
runtime/debug: don't run a GC when setting SetGCPercent negative
If the user is calling SetGCPercent(-1), they intend to disable GC.
They probably don't intend to run one. If they do, they can call
runtime.GC themselves.
Heschi Kreinick [Tue, 31 Jan 2017 19:09:14 +0000 (14:09 -0500)]
cmd/trace: Record mark assists in execution traces
During the mark phase of garbage collection, goroutines that allocate
may be recruited to assist. This change creates trace events for mark
assists and displays them similarly to sweep assists in the trace
viewer.
Mark assists are different than sweeps in that they can be preempted, so
displaying them in the trace viewer is a little tricky -- we may need to
synthesize multiple slices for one mark assist. This could have been
done in the parser instead, but I thought it might be preferable to keep
the parser as true to the event stream as possible.
Adam Langley [Thu, 9 Feb 2017 23:57:53 +0000 (15:57 -0800)]
crypto/x509: ignore CN if SAN extension present.
The code previously tested only whether DNS-name SANs were present in a
certificate which is only approximately correct. In fact, /any/ SAN
extension, including one with no DNS names, should cause the CN to be
ignored.
The s390x port was based on the ppc64 port and, because of the way the
port was done, inherited some instructions from it. ppc64 supports
3-operand (4-operand for FMADD etc.) floating point instructions
but s390x doesn't (the destination register is always an input) and
so these were emulated.
There is a bug in the emulation of FMADD whereby if the destination
register is also a source for the multiplication it will be
clobbered. This doesn't break any assembly code in the std lib but
could affect future work.
To fix this I have gone through the floating point instructions and
removed all unnecessary 3-/4-operand emulation. The compiler doesn't
need it and assembly writers don't need it, it's just a source of
bugs.
I've also deleted the FNMADD family of emulated instructions. They
aren't used anywhere.
Alberto Donizetti [Fri, 3 Feb 2017 09:36:47 +0000 (10:36 +0100)]
math: check overflow in amd64 Exp implementation
Unlike the pure go implementation used by every other architecture,
the amd64 asm implementation of Exp does not fail early if the
argument is known to overflow. Make it fail early.
Cost of the check is < 1ns (on an old Sandy Bridge machine):
name old time/op new time/op delta
Exp-4 18.3ns ± 1% 18.7ns ± 1% +2.08% (p=0.000 n=18+20)
Daniel Theophanes [Thu, 9 Feb 2017 05:38:51 +0000 (21:38 -0800)]
database/sql: ensure driverConns are closed if not returned to pool
Previously if a connection was requested but timed out during the
request and when acquiring the db.Lock the connection request
is fulfilled and the request is unable to be returned to the
connection pool, then then driver connection would not be closed.
No tests were added or modified because I was unable to determine
how to trigger this situation without something invasive.
It was rolled back because it broke a unit test in image/gif. The
image/gif code was fixed by 9ef65dbe0683634a2e8a557d12267d0309ae1570
"image/gif: fix frame-inside-image bounds checking".
The original commit message:
image: fix the overlap check in Rectangle.Intersect.
The doc comment for Rectangle.Intersect clearly states, "If the two
rectangles do not overlap then the zero rectangle will be returned."
Prior to this fix, calling Intersect on adjacent but non-overlapping
rectangles would return an empty but non-zero rectangle.
The fix essentially changes
if r.Min.X > r.Max.X || r.Min.Y > r.Max.Y { etc }
to
if r.Min.X >= r.Max.X || r.Min.Y >= r.Max.Y { etc }
(note that the > signs have become >= signs), but changing that line to:
if r.Empty() { etc }
seems clearer (and equivalent).
Change-Id: I2e3af1f1686064a573b2e513b39246fe60c03631
Reviewed-on: https://go-review.googlesource.com/36734 Reviewed-by: Rob Pike <r@golang.org>
Run-TryBot: Nigel Tao <nigeltao@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
cmd/compile: use constants directly for fast map access calls
CL 35554 taught order.go to use static variables
for constants that needed to be addressable for runtime routines.
However, there is one class of runtime routines that
do not actually need an addressable value: fast map access routines.
This CL teaches order.go to avoid using static variables
for addressability in those cases.
Instead, it avoids introducing a temp at all,
which the backend would just have to optimize away.
The semantics of the Go image.Rectangle type is that the In and
Intersects methods treat empty rectangles specially. There are multiple
valid representations of an empty image.Rectangle. One of them is the
zero image.Rectangle but there are others. They're obviously not all
equal in the == sense, so we shouldn't use != to check GIF's semantics.
Nathan Caza [Thu, 9 Feb 2017 00:42:52 +0000 (18:42 -0600)]
net/http: improve handling of errors in Dir.Open
The current implementation fails to produce an "IsNotExist" error on some
platforms (unix) for certain situations where it would be expected. This causes
downstream consumers, like FileServer, to emit 500 errors instead of a 404 for
some non-existant paths on certain platforms but not others.
As an example, os.Open("/index.html/foo") on a unix-type system will return
syscall.ENOTDIR, which os.IsNotExist cannot return true for (because the
error code is ambiguous without context). On windows, this same example
would result in os.IsNotExist returning true -- since the returned error is
specific.
This change alters Dir.Open to look up the tree for an "IsPermission" or
"IsNotExist" error to return, or a non-directory, returning os.ErrNotExist in
the last case. For all other error scenarios, the original error is returned.
This ensures that downstream code, like FileServer, receive errors that behave
the same across all platforms.
Robert Griesemer [Thu, 9 Feb 2017 21:22:37 +0000 (13:22 -0800)]
spec: refer to "not defined type" rather than "unnamed type" in conversions
We missed this in https://golang.org/cl/36213.
Thanks to Chris Hines for pointing it out.
For #18130.
Change-Id: I6279ab19966c4391c4b4458b21fd2527d3f949dd
Reviewed-on: https://go-review.googlesource.com/36691 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Robert Griesemer [Fri, 10 Feb 2017 00:00:23 +0000 (16:00 -0800)]
cmd/compile/internal/syntax: removed gcCompat code needed to pass orig. tests
The gcCompat mode was introduced to match the new parser's node position
setup exactly with the positions used by the original parser. Some of the
gcCompat adjustments were required to satisfy syntax error test cases,
and the rest were required to make toolstash cmp pass.
This change removes the former gcCompat adjustments and instead adjusts
the respective test cases as necessary. In some cases this makes the error
lines consistent with the ones reported by gccgo.
Where it has changed, the position associated with a given syntactic construct
is the position (line/col number) of the left-most token belonging to the
construct.
Change-Id: I5b60c00c5999a895c4d6d6e9b383c6405ccf725c
Reviewed-on: https://go-review.googlesource.com/36695
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Austin Clements [Thu, 9 Feb 2017 22:08:27 +0000 (17:08 -0500)]
cmd/compile: disallow combining nosplit and systemstack
go:systemstack works by tweaking the stack check prologue to check
against a different bound, while go:nosplit removes the stack check
prologue entirely. Hence, they can't be used together. Make the build
fail if they are.
Bryan C. Mills [Thu, 9 Feb 2017 19:34:38 +0000 (14:34 -0500)]
net/rpc: fix aliasing in TestAcceptExitAfterListenerClose
TestRPC writes to newServer and newServerAddr guarded with a
sync.Once.
TestAcceptExitAfterListenerClose was overwriting those variables,
which caused the second invocation of TestRPC within a single process
to fail.
A second invocation can occur as a result of running the test with
multiple values for the -cpu flag.
Paulo Flabiano Smorigo [Thu, 8 Dec 2016 14:06:34 +0000 (12:06 -0200)]
crypto/aes: improve performance for aes on ppc64le
Add asm implementation for AES in order to make use of VMX cryptographic
acceleration instructions for POWER8. There is a speed boost of over 10
times using those instructions:
Fixes #18076
old ns/op new ns/op delta
BenchmarkEncrypt-20 337 30.3 -91.00%
BenchmarkDecrypt-20 347 30.5a -91.21%
BenchmarkExpand-20 1180 130 -88.98%
old MB/s new MB/s speedup
BenchmarkEncrypt-20 47.38 527.68 11.13x
BenchmarkDecrypt-20 46.05 524.45 11.38x
Adam Langley [Wed, 8 Feb 2017 17:41:39 +0000 (09:41 -0800)]
crypto/x509: sort the list of fields used by CreateCertificateRequest.
Change-Id: I67589cb9e728e6c7df5ef6e981189193154338d3
Reviewed-on: https://go-review.googlesource.com/36559 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Adam Langley [Wed, 8 Feb 2017 17:40:14 +0000 (09:40 -0800)]
crypto/x509: CreateCertificateRequest reads ExtraExtensions, not Extensions.
Fixes #18899.
Change-Id: I6a4bf0aad9cf1dbe6691ba4e4c478fcb33c44528
Reviewed-on: https://go-review.googlesource.com/36558 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Adam Langley [Wed, 8 Feb 2017 17:28:53 +0000 (09:28 -0800)]
crypto/x509: document AuthorityKeyId and don't mutate it.
The AuthorityKeyId value from the template was used by
CreateCertificate, but that wasn't documented. Also, CreateCertificate
would stash a value in the template if it needed to override it, which
was wrong: template should be read-only.
Sameer Ajmani [Thu, 9 Feb 2017 15:44:26 +0000 (10:44 -0500)]
syscall: remove "use" function and calls from generated code.
Update syscall code generators to set build tags.
Regenerate zsyscall files, which makes the following changes:
- remove calls to "use"
- update build tags, adding missing ones in some cases
- "stat" renamed to "st" in some cases
- "libc_Utimes" renamed "libc_utimes" in one case
I'll mirror this change to x/sys/unix once committed.
Carlos Eduardo Seo [Thu, 2 Feb 2017 19:59:18 +0000 (17:59 -0200)]
cmd/asm, cmd/internal/obj/ppc64: Add ISA 2.05, 2.06 and 2.07 instructions.
This change adds instructions from ISA 2.05, 2.06 and 2.07 that are frequently
used in assembly optimizations for ppc64.
It also fixes two problems:
* the implementation of RLDICR[CC]/RLDICL[CC] did not consider all possible
cases for the bit mask.
* removed two non-existing instructions that were added by mistake in the VMX
implementation (VORL/VANDL).
Russ Cox [Sat, 4 Feb 2017 00:26:13 +0000 (19:26 -0500)]
time: optimize Now on darwin, windows
Fetch both monotonic and wall time together when possible.
Avoids skew and is cheaper.
Also shave a few ns off in conversion in package time.
Compared to current implementation (after monotonic changes):
name old time/op new time/op delta
Now 19.6ns ± 1% 9.7ns ± 1% -50.63% (p=0.000 n=41+49) darwin/amd64
Now 23.5ns ± 4% 10.6ns ± 5% -54.61% (p=0.000 n=30+28) windows/amd64
Now 54.5ns ± 5% 29.8ns ± 9% -45.40% (p=0.000 n=27+29) windows/386
More importantly, compared to Go 1.8:
name old time/op new time/op delta
Now 9.5ns ± 1% 9.7ns ± 1% +1.94% (p=0.000 n=41+49) darwin/amd64
Now 12.9ns ± 5% 10.6ns ± 5% -17.73% (p=0.000 n=30+28) windows/amd64
Now 15.3ns ± 5% 29.8ns ± 9% +94.36% (p=0.000 n=30+29) windows/386
This brings time.Now back in line with Go 1.8 on darwin/amd64 and windows/amd64.
It's not obvious why windows/386 is still noticeably worse than Go 1.8,
but it's better than before this CL. The windows/386 speed is not too
important; the changes just keep the two architectures similar.
Change-Id: If69b94970c8a1a57910a371ee91e0d4e82e46c5d
Reviewed-on: https://go-review.googlesource.com/36428
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Robert Griesemer [Thu, 9 Feb 2017 01:56:41 +0000 (17:56 -0800)]
cmd/compile/internal/parser: improved syntax error for incorrect if/for/switch header
Starting the error message with "expecting" rather than "missing"
causes the syntax error mechanism to add additional helpful info
(it recognizes "expecting" but not "missing").
Fixes #17328.
Change-Id: I8482ca5e5a6a6b22e0ed0d831b7328e264156334
Reviewed-on: https://go-review.googlesource.com/36637
Run-TryBot: Robert Griesemer <gri@golang.org> Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Robert Griesemer [Thu, 9 Feb 2017 01:30:45 +0000 (17:30 -0800)]
cmd/compile/internal/syntax: differentiate between ';' and '\n' in syntax errors
Towards better syntax error messages: With this change, the parser knows whether
a semicolon was an actual ';' in the source, or whether it was an automatically
inserted semicolon as result of a '\n' or EOF. Using this information in error
messages makes them more understandable.
For #17328.
Change-Id: I8cd9accee8681b62569d0ecef922d38682b401eb
Reviewed-on: https://go-review.googlesource.com/36636 Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Daniel Theophanes [Wed, 8 Feb 2017 18:32:22 +0000 (10:32 -0800)]
database/sql: do not exhaust connection pool on conn request timeout
Previously if a context was canceled while it was waiting for a
connection request, that connection request would leak.
To prevent this remove the pending connection request if the
context is canceled and ensure no connection has been sent on the channel.
This requires a change to how the connection requests are represented in the DB.
Kevin Burke [Wed, 8 Feb 2017 23:31:33 +0000 (15:31 -0800)]
database/sql: fix typo
Change-Id: I09fdcebb939417f18af09ed57f24460724cab64f
Reviewed-on: https://go-review.googlesource.com/36632 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Dmitri Shuralyov [Tue, 7 Feb 2017 15:57:33 +0000 (10:57 -0500)]
net/http: don't modify Request in StripPrefix
As of https://golang.org/cl/21530, rules are updated to state
that Handlers shouldn't modify the provided Request. This change
updates StripPrefix to follow that rule.
Resolves #18952.
Change-Id: I29bbb580722e871131fa75a97e6e038ec64fdfcd
Reviewed-on: https://go-review.googlesource.com/36483 Reviewed-by: Matt Layher <mdlayher@gmail.com> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Matt Layher <mdlayher@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
David Lazar [Fri, 2 Dec 2016 18:55:25 +0000 (13:55 -0500)]
cmd/compile: include linknames in export data
This lets the compiler inline functions that contain a linknamed symbol.
Previously, the net/http tests would fail to build with -l=4 because
the compiler inlined functions that call net.byteIndex (which is
linknamed to strings.IndexByte).
This changes only the compiler-specific export data, so we don't need to
bump the export format version number.
The following benchmark results show how the size of package export data
is impacted by this change. These benchmarks were created by compiling
the go1 benchmark and running `go tool pack x` to extract the export
data from the resulting .a files.
Максим Федосеев [Mon, 30 Jan 2017 12:11:01 +0000 (17:11 +0500)]
crypto/tls: fix link to more info about channel bindings
Link in the description of TLSUnique field of ConnectionState struct
leads to an article that is no longer available, so this commit
replaces it with link to a copy of the very same article on another
site.
Michael Munday [Tue, 7 Feb 2017 23:32:27 +0000 (18:32 -0500)]
cmd/compile: remove unnecessary type conversions on s390x
Some rules insert MOVDreg ops to ensure that type changes are kept.
If there is no type change (or the input is constant) then the MOVDreg
can be omitted, allowing further optimization.
Reduces the size of the .text section in the asm tool by ~33KB.
Daniel Theophanes [Tue, 7 Feb 2017 18:19:02 +0000 (10:19 -0800)]
database/sql: record the context error in Rows if canceled
Previously it was intended that Rows.Scan would return
an error and Rows.Err would return nil. This was problematic
because drivers could not differentiate between a normal
Rows.Close or a context cancel close.
The alternative is to require drivers to return a Scan to return
an error if the driver is closed while there are still rows to be read.
This is currently not how several drivers currently work and may be
difficult to detect when there are additional rows.
At the same time guard the the Rows.lasterr and prevent a close
while a Rows operation is active.
For the drivers that do not have Context methods, do not check for
context cancelation after the operation, but before for any operation
that may modify the database state.
Adam Langley [Wed, 8 Feb 2017 17:47:34 +0000 (09:47 -0800)]
crypto/tls: document that only tickets are supported.
This change clarifies that only ticket-based resumption is supported by
crypto/tls. It's not clear where to document this for a server,
although perhaps it's obvious there because there's nowhere to plug in
the storage that would be needed by SessionID-based resumption.
Ilya Tocar [Tue, 7 Feb 2017 22:00:39 +0000 (16:00 -0600)]
bytes: use Index in Count
Similar to https://go-review.googlesource.com/28586,
but for package bytes instead of strings.
This provides simpler code and some performance gain.
Also update strings.Count to use the same code.
Brad Fitzpatrick [Tue, 7 Feb 2017 23:15:24 +0000 (23:15 +0000)]
time: bound file reads and validate LoadLocation argument
Fixes #18985
Change-Id: I956117f47d1d2b453b4786c7b78c1c944defeca0
Reviewed-on: https://go-review.googlesource.com/36551 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Ian Lance Taylor [Sat, 4 Feb 2017 05:13:30 +0000 (21:13 -0800)]
runtime: use atomic ops for fwdSig, make sigtable immutable
The fwdSig array is accessed by the signal handler, which may run in
parallel with other threads manipulating it via the os/signal package.
Use atomic accesses to ensure that there are no problems.
Move the _SigHandling flag out of the sigtable array. This makes sigtable
immutable and safe to read from the signal handler.
Change-Id: Icfa407518c4ebe1da38580920ced764898dfc9ad
Reviewed-on: https://go-review.googlesource.com/36321
Run-TryBot: Ian Lance Taylor <iant@golang.org> Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Alberto Donizetti [Sat, 28 Jan 2017 10:29:53 +0000 (11:29 +0100)]
cmd/go: clarify that tag lists are space-separated
Apparently the current documentation is confusing users that
quickly skim the flags list at the top. Make very clear that
build tags are space-separated.
Updates #18800
Change-Id: I473552c5a2b70ca03d8bbbd2c76805f7f82b49a2
Reviewed-on: https://go-review.googlesource.com/35951 Reviewed-by: Daniel Martí <mvdan@mvdan.cc> Reviewed-by: Minux Ma <minux@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Alex Brainman [Tue, 6 Dec 2016 23:49:45 +0000 (10:49 +1100)]
os: make Stdin.Stat() return ModeCharDevice if Stdin is console
CL 20845 changed Stdin.Stat() so it returns ModeNamedPipe.
But introduced TestStatStdin does not test what Stdin.Stat()
returns when Stdin is console.
This CL adjusts both TestStatStdin and Stdin.Stat
implementations to handle console. Return ModeCharDevice
from Stdin.Stat() when Stdin is console on windows,
just like it does on unix.
Sameer Ajmani [Tue, 7 Feb 2017 17:27:29 +0000 (12:27 -0500)]
time: delete incorrect docs about day-of-month checks.
Documentation was introduced by CL https://golang.org/cl/14123
but that behavior was changed later by CL https://golang.org/cl/17710.
This CL deletes the stale paragraph.
Austin Clements [Fri, 13 Jan 2017 18:23:41 +0000 (13:23 -0500)]
runtime: fix confusion between _MaxMem and _MaxArena32
Currently both _MaxMem and _MaxArena32 represent the maximum arena
size on 32-bit hosts (except on MIPS32 where _MaxMem is confusingly
smaller than _MaxArena32).
Clean up sysAlloc so that it always uses _MaxMem, which is the maximum
arena size on both 32- and 64-bit architectures and is the arena size
we allocate auxiliary structures for. This lets us simplify and unify
some code paths and eliminate _MaxArena32.
Fixes #18651. mheap.sysAlloc currently assumes that if the arena is
small, we must be on a 32-bit machine and can therefore grow the arena
to _MaxArena32. This breaks down on darwin/arm64, where _MaxMem is
only 2 GB. As a result, on darwin/arm64, we only reserve spans and
bitmap space for a 2 GB heap, and if the application tries to allocate
beyond that, sysAlloc takes the 32-bit path, tries to grow the arena
beyond 2 GB, and panics when it tries to grow the spans array
allocation past its reserved size. This has probably been a problem
for several releases now, but was only noticed recently because
mapSpans didn't check the bounds on the span reservation until
recently. Most likely it corrupted the bitmap before. By using _MaxMem
consistently, we avoid thinking that we can grow the arena larger than
we have auxiliary structures for.
Change-Id: Ifef28cb746a3ead4b31c1d7348495c2242fef520
Reviewed-on: https://go-review.googlesource.com/35253 Reviewed-by: David Crawshaw <crawshaw@golang.org> Reviewed-by: Elias Naur <elias.naur@gmail.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Austin Clements [Fri, 13 Jan 2017 19:19:52 +0000 (14:19 -0500)]
runtime: simplify and cleanup mallocinit
mallocinit has evolved organically. Make a pass to clean it up in
various ways:
1. Merge the computation of spansSize and bitmapSize. These were
computed on every loop iteration of two different loops, but always
have the same value, which can be derived directly from _MaxMem.
This also avoids over-reserving these on MIPS, were _MaxArena32 is
larger than _MaxMem.
2. Remove the ulimit -v logic. It's been disabled for many releases
and the dead code paths to support it are even more wrong now than
they were when it was first disabled, since now we *must* reserve
spans and bitmaps for the full address space.
3. Make it clear that we're using a simple linear allocation to lay
out the spans, bitmap, and arena spaces. Previously there were a
lot of redundant pointer computations. Now we just bump p1 up as we
reserve the spaces.
Austin Clements [Fri, 13 Jan 2017 20:32:53 +0000 (15:32 -0500)]
runtime: make _MaxMem an untyped constant
Currently _MaxMem is a uintptr, which is going to complicate some
further changes. Make it untyped so we'll be able to do untyped math
on it before truncating it to a uintptr.
The runtime assembly is identical before and after this change on
{linux,windows}/{amd64,386}.
Updates #18651.
Change-Id: I0f64511faa9e0aa25179a556ab9f185ebf8c9cf8
Reviewed-on: https://go-review.googlesource.com/35251
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Rick Hudson <rlh@golang.org> Reviewed-by: David Crawshaw <crawshaw@golang.org>
Cherry Zhang [Mon, 6 Feb 2017 19:24:16 +0000 (14:24 -0500)]
cmd/compile: do not use "oaslit" for global
The compiler did not emit write barrier for assigning global with
struct literal, like global = T{} where T contains pointer.
The relevant code path is:
walkexpr OAS var_ OSTRUCTLIT
oaslit
anylit OSTRUCTLIT
walkexpr OAS var_ nil
return without adding write barrier
return true
break (without adding write barrier)
This CL makes oaslit not apply to globals. See also CL
https://go-review.googlesource.com/c/36355/ for an alternative
fix.
The downside of this is that it generates static data for zeroing
struct now. Also this only covers global. If there is any lurking
bug with implicit zeroing other than globals, this doesn't fix.
Russ Cox [Tue, 7 Feb 2017 16:59:38 +0000 (11:59 -0500)]
crypto/x509: check for new tls-ca-bundle.pem last
We added CentOS 7's /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem
to the list in response to #17549 - not being able to find any certs otherwise.
Now we have #18813, where CentOS 6 apparently has both that file
and /etc/pki/tls/certs/ca-bundle.crt, and the latter is complete while
the former is not.
Moving the new CentOS 7 file to the bottom of the list should fix both
problems: the CentOS 7 system that didn't have any of the other files
in the list will still find the new one, and existing systems will still
keep using what they were using instead of preferring the new path
that may or may not be complete on some systems.