Programs that call panic to crash after detecting a serious problem
may wish to use SetTraceback to force printing of all goroutines first.
Change-Id: Ib23ad9336f405485aabb642ca73f454a14c8baf3
Reviewed-on: https://go-review.googlesource.com/18043
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This future-proofs the Chdr64 structure against later versions of ELF
defining this field and declutters the documentation without changing
the layout of the struct.
This structure does not exist in the current release, so this change
is safe.
Change-Id: I239aad7243ddaf063a1f8cd521d8a50b30413281
Reviewed-on: https://go-review.googlesource.com/18028
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Copy the same sentence from Transport.TLSNextProto.
Change-Id: Ib67bf054e891a68be8ba466a8c52968363374d16
Reviewed-on: https://go-review.googlesource.com/18031
Reviewed-by: Russ Cox <rsc@golang.org>
Currently, if sigprof determines that the G is in user code (not cgo
or libcall code), it will only traceback the G stack if it can acquire
the stack barrier lock. However, it has no such restriction if the G
is in cgo or libcall code. Because cgo calls count as syscalls, stack
scanning and stack barrier installation can occur during a cgo call,
which means sigprof could attempt to traceback a G in a cgo call while
scanstack is installing stack barriers in that G's stack. As a result,
the following sequence of events can cause the sigprof traceback to
panic with "missed stack barrier":
1. M1: G1 performs a Cgo call (which, on Windows, is any system call,
which could explain why this is easier to reproduce on Windows).
2. M1: The Cgo call puts G1 into _Gsyscall state.
3. M2: GC starts a scan of G1's stack. It puts G1 in to _Gscansyscall
and acquires the stack barrier lock.
4. M3: A profiling signal comes in. On Windows this is a global
(though I don't think this matters), so the runtime stops M1 and
calls sigprof for G1.
5. M3: sigprof fails to acquire the stack barrier lock (because the
GC's stack scan holds it).
6. M3: sigprof observes that G1 is in a Cgo call, so it calls
gentraceback on G1 with its Cgo transition point.
7. M3: gentraceback on G1 grabs the currently empty g.stkbar slice.
8. M2: GC finishes scanning G1's stack and installing stack barriers.
9. M3: gentraceback encounters one of the just-installed stack
barriers and panics.
This commit fixes this by only allowing cgo tracebacks if sigprof can
acquire the stack barrier lock, just like in the regular user
traceback case.
For good measure, we put the same constraint on libcall tracebacks.
This case is probably already safe because, unlike cgo calls, libcalls
leave the G in _Grunning and prevent reaching a safe point, so
scanstack cannot run during a libcall. However, this also means that
sigprof will always acquire the stack barrier lock without contention,
so there's no cost to adding this constraint to libcall tracebacks.
Fixes#12528. For 1.5.3 (will require some backporting).
Change-Id: Ia5a4b8e3d66b23b02ffcd54c6315c81055c0cec2
Reviewed-on: https://go-review.googlesource.com/18023
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Currently, setNextBarrierPC manipulates the stack barriers without
acquiring the stack barrier lock. This is mostly okay because
setNextBarrierPC also runs synchronously on the G and prevents safe
points, but this doesn't prevent a sigprof from occurring during a
setNextBarrierPC and performing a traceback.
Given that setNextBarrierPC simply sets one entry in the stack barrier
array, this is almost certainly safe in reality. However, given that
this depends on a subtle argument, which may not hold in the future,
and that setNextBarrierPC almost never happens, making it nowhere near
performance-critical, we can simply acquire the stack barrier lock and
be sure that the synchronization will work.
Updates #12528. For 1.5.3.
Change-Id: Ife696e10d969f190157eb1cbe762a2de2ebce079
Reviewed-on: https://go-review.googlesource.com/18022
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Update docs on ResponseWriter and Handler around concurrency.
Also add a test.
The Handler docs were old and used "object" a lot. It was also too
ServeMux-centric.
Fixes#13050
Updates #13659 (new issue found in http2 while writing the test)
Change-Id: I25f53d5fa54f1c9d579d3d0f191bf3d94b1a251b
Reviewed-on: https://go-review.googlesource.com/17982
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
The test for non-package main top-level inputs is done while parsing
the export data. Issue #13468 happened because we were not parsing
the export data when using compiler-generated archives
(that is, when using go tool compile -pack).
Fix this by parsing the export data even for archives.
However, that turns up a different problem: the export data check
reports (one assumes spurious) skew errors now, because it has
not been run since Go 1.2.
(Go 1.3 was the first release to use go tool compile -pack.)
Since the code hasn't run since Go 1.2, it can't be that important.
Since it doesn't work today, just delete it.
Figuring out how to make this code work with Robert's export
format was one of the largest remaining TODOs for that format.
Now we don't have to.
Fixes#13468 and makes the world a better place.
Change-Id: I40a4b284cf140d49d48b714bd80762d6889acdb9
Reviewed-on: https://go-review.googlesource.com/17976
Reviewed-by: Robert Griesemer <gri@golang.org>
Since we allow non-200 responses from HTTPS in normal operation,
it seems odd to reject them in -insecure operation.
Fixes#13037 (again).
Change-Id: Ie232f7544ab192addfad407525888db6b967befe
Reviewed-on: https://go-review.googlesource.com/17945
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The change here is to move the closeBody call into the if block.
The logging adjustments are just arranging to tell the truth:
in particular if we're not in insecure mode and we get a non-200
error then we do not actually ignore the response
(except as caused by closing the body incorrectly).
As the comment below the change indicates, it is intentional that
we process non-200 pages. The code does process them, because
the if err != nil || status != 200 block does not return.
But that block does close the body, which depending on timing
can apparently poison the later read from the body.
See #13037's initial report:
$ go get -v bosun.org/cmd/bosun/cache
Fetching https://bosun.org/cmd/bosun/cache?go-get=1
ignoring https fetch with status code 404
Parsing meta tags from https://bosun.org/cmd/bosun/cache?go-get=1 (status code 404)
import "bosun.org/cmd/bosun/cache": parsing bosun.org/cmd/bosun/cache: http: read on closed response body
package bosun.org/cmd/bosun/cache: unrecognized import path "bosun.org/cmd/bosun/cache"
The log print about ignoring the https fetch is not strictly true,
since the next thing that happened was parsing the body of that fetch.
But the read on the closed response body failed during parsing.
Moving the closeBody to happen only when we're about to discard the
result and start over (that is, only in -insecure mode) fixes the parse.
At least it should fix the parse. I can't seem to break the parse anymore,
because of #13648 (close not barring future reads anymore),
but this way is clearly better than the old way. If nothing else the old code
closed the body twice when err != nil and -insecure was not given.
Fixes#13037.
Change-Id: Idf57eceb6d5518341a2f7f75eb8f8ab27ed4e0b4
Reviewed-on: https://go-review.googlesource.com/17944
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This caused #13657.
Reverting fixes#13657.
I was trying to be helpful by fixing #12313,
but I don't need the fix myself.
Will leave for someone with more motivation.
This reverts commit 3e9f063670.
Change-Id: Ifc78a6196f23e0f58e3b9ad7340e207a2d5de0a6
Reviewed-on: https://go-review.googlesource.com/17977
Reviewed-by: Russ Cox <rsc@golang.org>
Patch from Russ.
No bug identified, but I didn't search exhaustively. The new code is
easier to read.
Fixes#13621
Change-Id: Ifda936e4101116fa254ead950b5fe06adb14e977
Reviewed-on: https://go-review.googlesource.com/17981
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Thanks to @toxeus on GitHub for the test case.
Fixes#12612.
Change-Id: I0c32fbe5044f3552053460a5347c062568093dff
Reviewed-on: https://go-review.googlesource.com/17974
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Also update many call sites where I forgot that the permission
argument is going to be masked by umask.
Fixes#12692.
Change-Id: I52b315b06236122ca020950447863fa396b68abd
Reviewed-on: https://go-review.googlesource.com/17950
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This updates the bundled copy of x/net/http2 to git rev d2ecd08
for https://golang.org/cl/17912 (http2: send client trailers)
and enables the final Trailer test for http2.
Fixes#13557
Change-Id: Iaa15552b82bf7a2cb01b7787a2e1ec5ee680a9d3
Reviewed-on: https://go-review.googlesource.com/17935
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Also include test for interface state (up or down).
Updates #13606
Change-Id: I03538d65525ddd9c2d0254761861c2df7fc5bd5a
Reviewed-on: https://go-review.googlesource.com/17850
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Mikio Hara <mikioh.mikioh@gmail.com>
Run-TryBot: Russ Cox <rsc@golang.org>
This makes go get gitserver/~user/repo.git/foo work.
Fixes#9193.
Change-Id: I8c9d4096903288f7f0e82d6ed1aa78bf038fb81a
Reviewed-on: https://go-review.googlesource.com/17952
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This doesn't happen enough in the tests to be worth debugging.
Empirically, I expect this to add 5 seconds to the overall 'go test -short cmd/go'
on systems with precise file systems, and nothing on systems without them
(like my Mac).
Fixes#12205.
Change-Id: I0a17cb37bdedcfc0f921c5ee658737f1698c153b
Reviewed-on: https://go-review.googlesource.com/17953
Reviewed-by: Ian Lance Taylor <iant@golang.org>
No test because the code has no test.
Fixes#12313.
Change-Id: I2cfd0a0422c0cd76f0371c2d3bbbdf5bb3b3f1eb
Reviewed-on: https://go-review.googlesource.com/17951
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This is an attempt to document the current state of signal handling.
It's not intended to describe the best way to handle signals. Future
changes to signal handling should update these docs as appropriate.
update #9896.
Change-Id: I3c50af5cc641357b57dfe90ae1c7883a7e1ec059
Reviewed-on: https://go-review.googlesource.com/17877
Reviewed-by: Russ Cox <rsc@golang.org>
Document that ListenAndServe and ListenAndServeTLS also set TCP
keep-alives.
Fixes#12748
Change-Id: Iba2e8a58dd657eba326db49a6c872e2d972883a4
Reviewed-on: https://go-review.googlesource.com/17681
Reviewed-by: Russ Cox <rsc@golang.org>
Commit dd5e14a751 ensured that no data
could be read for header-only files regardless of what the Header.Size
said. We should document this fact in Reader.Read.
Updates #13647
Change-Id: I4df9a2892bc66b49e0279693d08454bf696cfa31
Reviewed-on: https://go-review.googlesource.com/17913
Reviewed-by: Russ Cox <rsc@golang.org>
With certain names and search domain configurations the
returned error would be one encountered while querying a
generated name instead of the original name. This caused
confusion when a manual check of the same name produced
different results.
Now prefer errors encountered for the original name.
Also makes the low-level DNS connection plumbing swappable
in tests enabling tighter control over responses without
relying on the network.
Fixes#12712
Updates #13295
Change-Id: I780d628a762006bb11899caf20b5f97b462a717f
Reviewed-on: https://go-review.googlesource.com/16953
Reviewed-by: Russ Cox <rsc@golang.org>
Thanks to Albert Hafvenström for the diagnosis.
Fixes#11246.
Change-Id: I2b9e670c0ecf6aa01e5bf4d7a402619e93cc4f4a
Reviewed-on: https://go-review.googlesource.com/17942
Reviewed-by: Ian Lance Taylor <iant@golang.org>
If cgo is turned off, there may not be an external linker available.
Fixes#13450.
Change-Id: Idbf3f3f57b4bb3908b67264f96d276acc952102a
Reviewed-on: https://go-review.googlesource.com/17941
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Maybe it will say something that helps the user understand the problem.
Note that we can't use os/exec.ExitError's new Stderr field because
cmd/dist is compiled with Go 1.4.
Fixes#13099.
Change-Id: I4b5910434bf324d1b85107002a64684d8ba14dc8
Reviewed-on: https://go-review.googlesource.com/17940
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This uses weak declarations so that it will work with current versions
of gccgo that do not support pointer checking.
Change-Id: Ia34507e3231ac60517cb6834f0b673764715a256
Reviewed-on: https://go-review.googlesource.com/17429
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
I updated this in the previous commit (https://golang.org/cl/17931)
but noticed a typo. and it still wasn't great.
The Go 1.5 text was too brief to know how to use it:
// Trailer maps trailer keys to values, in the same
// format as the header.
Change-Id: I33c49b6a4a7a3596735a4cc7865ad625809da900
Reviewed-on: https://go-review.googlesource.com/17932
Reviewed-by: Russ Cox <rsc@golang.org>
The new flag -args stops flag processing, leaving the rest of the command line
to be passed to the underlying test binary verbatim. Thus, both of these pass
a literal -v -n on the test binary command line, without putting the go command
into verbose mode or disabling execution of commands:
go test . -args -v -n
go test -args -v -n
Also try to make the documentation a bit clearer.
Fixes#7221.
Fixes#12177.
Change-Id: Ief9e830a6fbb9475d96011716a86e2524a35eceb
Reviewed-on: https://go-review.googlesource.com/17775
Reviewed-by: Rob Pike <r@golang.org>
No longer needed - the change to 'go test' was rolled back.
This reverts commit 2c96e5d2fc.
Change-Id: Ibe9c5f48e3e4cbbbde2f5c8c516b2987ebba55ae
Reviewed-on: https://go-review.googlesource.com/17776
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
This CL updates the bundled copy of x/net/http2 to include
https://golang.org/cl/17930 and enables the previously-skipped tests
TestTrailersServerToClient_h2 and TestTrailersServerToClient_Flush_h2.
It also updates the docs on http.Response.Trailer to describe how to
use it. No change in rules. Just documenting the old unwritten rules.
(there were tests locking in the behavior, and misc docs and examples
scattered about, but not on http.Response.Trailer itself)
Updates #13557
Change-Id: I6261d439f6c0d17654a1a7928790e8ffed16df6c
Reviewed-on: https://go-review.googlesource.com/17931
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Blake Mizerany <blake.mizerany@gmail.com>
This change adds a check after computing an RSA signature that the
signature is correct. This prevents an error in the CRT computation from
leaking the private key. See references in the linked bug.
benchmark old ns/op new ns/op delta
BenchmarkRSA2048Sign-3 5713305 6225215 +8.96%
Fixes#12453
Change-Id: I1f24e0b542f7c9a3f7e7ad4e971db3dc440ed3c1
Reviewed-on: https://go-review.googlesource.com/17862
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
CL 17821 used syscall.CancelIoEx to cancel outstanding connect
call, but did not check for syscall.CancelIoEx return value.
Also I am worried about introducing race here. We should use
proper tools available for us instead. For example, we could
use fd.setWriteDeadline just like unix version does. Do that.
Change-Id: Idb9a03c8c249278ce3e2a4c49cc32445d4c7b065
Reviewed-on: https://go-review.googlesource.com/17920
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
Fixes#12411.
Change-Id: I2202a754c7750e3b2119e3744362c98ca0d2433e
Reviewed-on: https://go-review.googlesource.com/17818
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This broke a number of common "go test" invocations.
Will fix the original concern differently.
This reverts commit 6acb4d944d.
Fixes#13583.
Change-Id: If582b81061df28173c698bed1d7d8283b0713cae
Reviewed-on: https://go-review.googlesource.com/17773
Reviewed-by: Rob Pike <r@golang.org>
The old test was in client_test.go but was a mix of four things:
- clients writing trailers
- servers reading trailers
- servers writing trailers
- clients reading trailers
It definitely wasn't just about clients.
This moves it into clientserver_test.go and separates it into two
halves:
- servers writing trailers + clients reading trailers
- clients writing trailers + servers reading trailers
Which still isn't ideal, but is much better, and easier to read.
Updates #13557
Change-Id: I8c3e58a1f974c1b10bb11ef9b588cfa0f73ff5d9
Reviewed-on: https://go-review.googlesource.com/17895
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Blake Mizerany <blake.mizerany@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Also fix bug reported in CL 17510.
Found during fix of #13515 in CL 17672, but separate from the fix.
Change-Id: I4b1024569a98f5cfd2ebb442ec3d64356164d284
Reviewed-on: https://go-review.googlesource.com/17673
Reviewed-by: Robert Griesemer <gri@golang.org>
I've already turned away one attempt to remove this field.
As the comment above the struct says, many tools know the layout.
The field cannot simply be removed.
It was one thing to remove the fields name, but the TODO should
not have been added.
Change-Id: If40eacf0eb35835082055e129e2b88333a0731b9
Reviewed-on: https://go-review.googlesource.com/17741
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This fix, plus a one-line change to golang.org/x/tools/go/loader,
is sufficient to let that loader package process source code
using vendored packages. For example,
GOPATH="" ssadump net/http # uses vendored http2
used to fail, not able to find net/http's import of the vendored
copy of golang.org/x/net/http2/hpack.
This CL plus the fix to loader (CL 17727) suffices to get ssadump working,
as well as - I expect - most other source code processing built
on golang.org/x/tools/go/loader.
Fixes#12278.
Change-Id: I83715e757419171159f67d49bb453636afdd91f0
Reviewed-on: https://go-review.googlesource.com/17726
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TestMemStats currently requires that NumGC != 0, but GC may
legitimately not have run (for example, if this test runs first, or
GOGC is set high, etc). Accept NumGC == 0 and instead sanity check
NumGC by making sure that all pause times after NumGC are 0.
Fixes#11989.
Change-Id: I4203859fbb83292d59a509f2eeb24d6033e7aabc
Reviewed-on: https://go-review.googlesource.com/17830
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Mikio Hara <mikioh.mikioh@gmail.com>
This simply copies the current version of math/big into the
compiler directory. The change was created automatically by
running cmd/compile/internal/big/vendor.bash. No other manual
changes.
Change-Id: Ica225d196b3ac10dfd9d4dc1e4e4ef0b22812ff9
Reviewed-on: https://go-review.googlesource.com/17900
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The Transport had a delicate protocol between its readLoop goroutine
and the goroutine calling RoundTrip. The basic concern is that the
caller's RoundTrip goroutine wants to wait for either a
connection-level error (the conn dying) or the response. But sometimes
both happen: there's a valid response (without a body), but the conn
is also going away. Both goroutines' logic dealing with this had grown
large and complicated with hard-to-follow comments over the years.
Simplify and document. Pull some bits into functions and do all
bodyless stuff in one place (it's special enough), rather than having
a bunch of conditionals scattered everywhere. One test is no longer
even applicable since the race it tested is no longer possible (the
code doesn't exist).
The bug that this fixes is that when the Transport reads a bodyless
response from a server, it was returning that response before
returning the persistent connection to the idle pool. As a result,
~1/1000 of serial requests would end up creating a new connection
rather than re-using the just-used connection due to goroutine
scheduling chance. Instead, this now adds bodyless responses'
connections back to the idle pool first, then sends the response to
the RoundTrip goroutine, but making sure that the RoundTrip goroutine
is outside of its select on the connection dying.
There's a new buffered channel involved now, which is a minor
complication, but it's much more self-contained and well-documented
than the previous complexity. (The alternative of making the
responseAndError channel itself unbuffered is too invasive and risky
at this point; it would require a number of changes to avoid
deadlocked goroutines in error cases)
In any case, flakes look to be gone now. We'll see if trybots agree.
Fixes#13633
Change-Id: I95a22942b2aa334ae7c87331fddd751d4cdfdffc
Reviewed-on: https://go-review.googlesource.com/17890
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
This matches SIGEMT on other systems that use it (SIGEMT is not used
for most linux systems).
Change-Id: If394c06c9ed1cb3ea2564385a8edfbed8b5566d1
Reviewed-on: https://go-review.googlesource.com/17874
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
Also fixed conversion bug and added corresponding test case.
Change-Id: I26f143fbc8d40a6d073ecb095e61b461495f3d68
Reviewed-on: https://go-review.googlesource.com/17872
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
This might deflake it. Or it'll at least give us more debugging clues.
Fixes#13626 maybe
Change-Id: Ie8cd0375d60dad033ec6a64830a90e7b9152a3d9
Reviewed-on: https://go-review.googlesource.com/17825
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
CloseNotifier wasn't well specified previously. This CL simplifies its
implementation, clarifies the public documentation on CloseNotifier,
clarifies internal documentation on conn, and fixes two CloseNotifier
bugs in the process.
The main change, though, is tightening the rules and expectations for using
CloseNotifier:
* the caller must consume the Request.Body first (old rule, unwritten)
* the received value is the "true" value (old rule, unwritten)
* no promises for channel sends after Handler returns (old rule, unwritten)
* a subsequent pipelined request fires the CloseNotifier (new behavior;
previously it never fired and thus effectively deadlocked as in #13165)
* advise that it should only be used without HTTP/1.1 pipelining (use HTTP/2
or non-idempotent browsers). Not that browsers actually use pipelining.
The main implementation change is that each Handler now gets its own
CloseNotifier channel value, rather than sharing one between the whole
conn. This means Handlers can't affect subsequent requests. This is
how HTTP/2's Server works too. The old docs never clarified a behavior
either way. The other side effect of each request getting its own
CloseNotifier channel is that one handler can't "poison" the
underlying conn preventing subsequent requests on the same connection
from using CloseNotifier (this is #9763).
In the old implementation, once any request on a connection used
ClosedNotifier, the conn's underlying bufio.Reader source was switched
from the TCPConn to the read side of the pipe being fed by a
never-ending copy. Since it was impossible to abort that never-ending
copy, we could never get back to a fresh state where it was possible
to return the underlying TCPConn to callers of Hijack. Now, instead of
a never-ending Copy, the background goroutine doing a Read from the
TCPConn (or *tls.Conn) only reads a single byte. That single byte
can be in the request body, a socket timeout error, io.EOF error, or
the first byte of the second body. In any case, the new *connReader
type stitches sync and async reads together like an io.MultiReader. To
clarify the flow of Read data and combat the complexity of too many
wrapper Reader types, the *connReader absorbs the io.LimitReader
previously used for bounding request header reads. The
liveSwitchReader type is removed. (an unused switchWriter type is also
removed)
Many fields on *conn are also documented more fully.
Fixes#9763 (CloseNotify + Hijack together)
Fixes#13165 (deadlock with CloseNotify + pipelined requests)
Change-Id: I40abc0a1992d05b294d627d1838c33cbccb9dd65
Reviewed-on: https://go-review.googlesource.com/17750
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently, sysmon triggers a forced GC solely based on
memstats.last_gc. However, memstats.last_gc isn't updated until mark
termination, so once sysmon starts triggering forced GC, it will keep
triggering them until GC finishes. The first of these actually starts
a GC; the remainder up to the last print "GC forced", but gcStart
returns immediately because gcphase != _GCoff; then the last may start
another GC if the previous GC finishes (and sets last_gc) between
sysmon triggering it and gcStart checking the GC phase.
Fix this by expanding the condition for starting a forced GC to also
require that no GC is currently running. This, combined with the way
forcegchelper blocks until the GC cycle is started, ensures sysmon
only starts one GC when the time exceeds the forced GC threshold.
Fixes#13458.
Change-Id: Ie6cf841927f6085136be3f45259956cd5cf10d23
Reviewed-on: https://go-review.googlesource.com/17819
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
The addition of stack barrier locking to copystack subsumes the
partial fix from commit bbd1a1c for SIGPROF during copystack. With the
stack barrier locking, this commit simplifies the rule in sigprof to:
the user stack can be traced only if sigprof can acquire the stack
barrier lock.
Updates #12932, #13362.
Change-Id: I1c1f80015053d0ac7761e9e0c7437c2aba26663f
Reviewed-on: https://go-review.googlesource.com/17192
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
After fixing #13587, I noticed that the "OAS2FUNC in disguise" block
looked like it probably needed write barriers too. However, testing
revealed the multi-value "return f()" case was already being handled
correctly.
It turns out this block is dead code due to "return f()" already being
transformed into "t1, t2, ..., tN := f(); return t1, t2, ..., tN" by
orderstmt when f is a multi-valued function.
Updates #13587.
Change-Id: Icde46dccc55beda2ea5fd5fcafc9aae26cec1552
Reviewed-on: https://go-review.googlesource.com/17759
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Currently, runtime/debug.SetGCPercent does not adjust the controller
trigger ratio. As a result, runtime reductions of GOGC don't take full
effect until after one more concurrent cycle has happened, which
adjusts the trigger ratio to account for the new gcpercent.
Fix this by lowering the trigger ratio if necessary in setGCPercent.
Change-Id: I4d23e0c58d91939b86ac60fa5d53ef91d0d89e0c
Reviewed-on: https://go-review.googlesource.com/17813
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Currently we drop worldsema and then print the gctrace. We did this so
that if stderr is a pipe or a blocked terminal, blocking on printing
the gctrace would not block another GC from starting. However, this is
a bit of a fool's errand because a blocked runtime print will block
the whole M/P, so after GOMAXPROCS GC cycles, the whole system will
freeze. Furthermore, now this is much less of an issue because
allocation will block indefinitely if it can't start a GC (whereas it
used to be that allocation could run away). Finally, this allows
another GC cycle to start while the previous cycle is printing the
gctrace, which leads to races on reading various statistics to print
them and the next GC cycle overwriting those statistics.
Fix this by moving the release of worldsema after the gctrace print.
Change-Id: I3d044ea0f77d80f3b4050af6b771e7912258662a
Reviewed-on: https://go-review.googlesource.com/17812
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Rick Hudson <rlh@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Currently we reset the sweep stats just after gcMarkTermination starts
the world and releases worldsema. However, background sweeping can
start the moment we start the world and, in fact, pause sweeping can
start the moment we release worldsema (because another GC cycle can
start up), so these need to be cleared before starting the world.
Change-Id: I95701e3de6af76bb3fbf2ee65719985bf57d20b2
Reviewed-on: https://go-review.googlesource.com/17811
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Currently, we update memstats.heap_live from mcache.local_cachealloc
whenever we lock the heap (e.g., to obtain a fresh span or to release
an unused span). However, under the right circumstances,
local_cachealloc can accumulate allocations up to the size of
the *entire heap* without flushing them to heap_live. Specifically,
since span allocations from an mcentral don't lock the heap, if a
large number of pages are held in an mcentral and the application
continues to use and free objects of that size class (e.g., the
BinaryTree17 benchmark), local_cachealloc won't be flushed until the
mcentral runs out of spans.
This is a problem because, unlike many of the memory statistics that
are purely informative, heap_live is used to determine when the
garbage collector should start and how hard it should work.
This commit eliminates local_cachealloc, instead atomically updating
heap_live directly. To control contention, we do this only when
obtaining a span from an mcentral. Furthermore, we make heap_live
conservative: allocating a span assumes that all free slots in that
span will be used and accounts for these when the span is
allocated, *before* the objects themselves are. This is important
because 1) this triggers the GC earlier than necessary rather than
potentially too late and 2) this leads to a conservative GC rate
rather than a GC rate that is potentially too low.
Alternatively, we could have flushed local_cachealloc when it passed
some threshold, but this would require determining a threshold and
would cause heap_live to underestimate the true value rather than
overestimate.
Fixes#12199.
name old time/op new time/op delta
BinaryTree17-12 2.88s ± 4% 2.88s ± 1% ~ (p=0.470 n=19+19)
Fannkuch11-12 2.48s ± 1% 2.48s ± 1% ~ (p=0.243 n=16+19)
FmtFprintfEmpty-12 50.9ns ± 2% 50.7ns ± 1% ~ (p=0.238 n=15+14)
FmtFprintfString-12 175ns ± 1% 171ns ± 1% -2.48% (p=0.000 n=18+18)
FmtFprintfInt-12 159ns ± 1% 158ns ± 1% -0.78% (p=0.000 n=19+18)
FmtFprintfIntInt-12 270ns ± 1% 265ns ± 2% -1.67% (p=0.000 n=18+18)
FmtFprintfPrefixedInt-12 235ns ± 1% 234ns ± 0% ~ (p=0.362 n=18+19)
FmtFprintfFloat-12 309ns ± 1% 308ns ± 1% -0.41% (p=0.001 n=18+19)
FmtManyArgs-12 1.10µs ± 1% 1.08µs ± 0% -1.96% (p=0.000 n=19+18)
GobDecode-12 7.81ms ± 1% 7.80ms ± 1% ~ (p=0.425 n=18+19)
GobEncode-12 6.53ms ± 1% 6.53ms ± 1% ~ (p=0.817 n=19+19)
Gzip-12 312ms ± 1% 312ms ± 2% ~ (p=0.967 n=19+20)
Gunzip-12 42.0ms ± 1% 41.9ms ± 1% ~ (p=0.172 n=19+19)
HTTPClientServer-12 63.7µs ± 1% 63.8µs ± 1% ~ (p=0.639 n=19+19)
JSONEncode-12 16.4ms ± 1% 16.4ms ± 1% ~ (p=0.954 n=19+19)
JSONDecode-12 58.5ms ± 1% 57.8ms ± 1% -1.27% (p=0.000 n=18+19)
Mandelbrot200-12 3.86ms ± 1% 3.88ms ± 0% +0.44% (p=0.000 n=18+18)
GoParse-12 3.67ms ± 2% 3.66ms ± 1% -0.52% (p=0.001 n=18+19)
RegexpMatchEasy0_32-12 100ns ± 1% 100ns ± 0% ~ (p=0.257 n=19+18)
RegexpMatchEasy0_1K-12 347ns ± 1% 347ns ± 1% ~ (p=0.527 n=18+18)
RegexpMatchEasy1_32-12 83.7ns ± 2% 83.1ns ± 2% ~ (p=0.096 n=18+19)
RegexpMatchEasy1_1K-12 509ns ± 1% 505ns ± 1% -0.75% (p=0.000 n=18+19)
RegexpMatchMedium_32-12 130ns ± 2% 129ns ± 1% ~ (p=0.962 n=20+20)
RegexpMatchMedium_1K-12 39.5µs ± 2% 39.4µs ± 1% ~ (p=0.376 n=20+19)
RegexpMatchHard_32-12 2.04µs ± 0% 2.04µs ± 1% ~ (p=0.195 n=18+17)
RegexpMatchHard_1K-12 61.4µs ± 1% 61.4µs ± 1% ~ (p=0.885 n=19+19)
Revcomp-12 540ms ± 2% 542ms ± 4% ~ (p=0.552 n=19+17)
Template-12 69.6ms ± 1% 71.2ms ± 1% +2.39% (p=0.000 n=20+20)
TimeParse-12 357ns ± 1% 357ns ± 1% ~ (p=0.883 n=18+20)
TimeFormat-12 379ns ± 1% 362ns ± 1% -4.53% (p=0.000 n=18+19)
[Geo mean] 62.0µs 61.8µs -0.44%
name old time/op new time/op delta
XBenchGarbage-12 5.89ms ± 2% 5.81ms ± 2% -1.41% (p=0.000 n=19+18)
Change-Id: I96b31cca6ae77c30693a891cff3fe663fa2447a0
Reviewed-on: https://go-review.googlesource.com/17748
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
deductSweepCredit expects the size in bytes of the span being
allocated, but mCentral_CacheSpan passes the size of a single object
in the span. As a result, we don't sweep enough on that call and when
mCentral_CacheSpan later calls reimburseSweepCredit, it's very likely
to underflow mheap_.spanBytesAlloc, which causes the next call to
deductSweepCredit to think it owes a huge number of pages and finish
off the whole sweep.
In addition to causing the occasional allocation that triggers the
full sweep to be potentially extremely expensive relative to other
allocations, this can indirectly slow down many other allocations.
deductSweepCredit uses sweepone to sweep spans, which returns
fully-unused spans to the heap, where these spans are freed and
coalesced with neighboring free spans. On the other hand, when
mCentral_CacheSpan sweeps a span, it does so with the intent to
immediately reuse that span and, as a result, will not return the span
to the heap even if it is fully unused. This saves on the cost of
locking the heap, finding a span, and initializing that span. For
example, before this change, with GOMAXPROCS=1 (or the background
sweeper disabled) BinaryTree17 returned roughly 220K spans to the heap
and allocated new spans from the heap roughly 232K times. After this
change, it returns 1.3K spans to the heap and allocates new spans from
the heap 39K times. (With background sweeping these numbers are
effectively unchanged because the background sweeper sweeps almost all
of the spans with sweepone; however, parallel sweeping saves more than
the cost of allocating spans from the heap.)
Fixes#13535.
Fixes#13589.
name old time/op new time/op delta
BinaryTree17-12 3.03s ± 1% 2.86s ± 4% -5.61% (p=0.000 n=18+20)
Fannkuch11-12 2.48s ± 1% 2.49s ± 1% ~ (p=0.060 n=17+20)
FmtFprintfEmpty-12 50.7ns ± 1% 50.9ns ± 1% +0.43% (p=0.025 n=15+16)
FmtFprintfString-12 174ns ± 2% 174ns ± 2% ~ (p=0.539 n=19+20)
FmtFprintfInt-12 158ns ± 1% 158ns ± 1% ~ (p=0.300 n=18+20)
FmtFprintfIntInt-12 269ns ± 2% 269ns ± 2% ~ (p=0.784 n=20+18)
FmtFprintfPrefixedInt-12 233ns ± 1% 234ns ± 1% ~ (p=0.389 n=18+18)
FmtFprintfFloat-12 309ns ± 1% 310ns ± 1% +0.25% (p=0.048 n=18+18)
FmtManyArgs-12 1.10µs ± 1% 1.10µs ± 1% ~ (p=0.259 n=18+19)
GobDecode-12 7.81ms ± 1% 7.72ms ± 1% -1.17% (p=0.000 n=19+19)
GobEncode-12 6.56ms ± 0% 6.55ms ± 1% ~ (p=0.433 n=17+19)
Gzip-12 318ms ± 2% 317ms ± 1% ~ (p=0.578 n=19+18)
Gunzip-12 42.1ms ± 2% 42.0ms ± 0% -0.45% (p=0.007 n=18+16)
HTTPClientServer-12 63.9µs ± 1% 64.0µs ± 1% ~ (p=0.146 n=17+19)
JSONEncode-12 16.4ms ± 1% 16.4ms ± 1% ~ (p=0.271 n=19+19)
JSONDecode-12 58.1ms ± 1% 58.0ms ± 1% ~ (p=0.152 n=18+18)
Mandelbrot200-12 3.85ms ± 0% 3.85ms ± 0% ~ (p=0.126 n=19+18)
GoParse-12 3.71ms ± 1% 3.64ms ± 1% -1.86% (p=0.000 n=20+18)
RegexpMatchEasy0_32-12 100ns ± 2% 100ns ± 1% ~ (p=0.588 n=20+20)
RegexpMatchEasy0_1K-12 346ns ± 1% 347ns ± 1% +0.27% (p=0.014 n=17+20)
RegexpMatchEasy1_32-12 82.9ns ± 3% 83.5ns ± 3% ~ (p=0.096 n=19+20)
RegexpMatchEasy1_1K-12 506ns ± 1% 506ns ± 1% ~ (p=0.530 n=19+19)
RegexpMatchMedium_32-12 129ns ± 2% 129ns ± 1% ~ (p=0.566 n=20+19)
RegexpMatchMedium_1K-12 39.4µs ± 1% 39.4µs ± 1% ~ (p=0.713 n=19+20)
RegexpMatchHard_32-12 2.05µs ± 1% 2.06µs ± 1% +0.36% (p=0.008 n=18+20)
RegexpMatchHard_1K-12 61.6µs ± 1% 61.7µs ± 1% ~ (p=0.286 n=19+20)
Revcomp-12 538ms ± 1% 541ms ± 2% ~ (p=0.081 n=18+19)
Template-12 71.5ms ± 2% 71.6ms ± 1% ~ (p=0.513 n=20+19)
TimeParse-12 357ns ± 1% 357ns ± 1% ~ (p=0.935 n=19+18)
TimeFormat-12 352ns ± 1% 352ns ± 1% ~ (p=0.293 n=19+20)
[Geo mean] 62.0µs 61.9µs -0.21%
name old time/op new time/op delta
XBenchGarbage-12 5.83ms ± 2% 5.86ms ± 3% ~ (p=0.247 n=19+20)
Change-Id: I790bb530adace27ccf25d372f24a11954b88443c
Reviewed-on: https://go-review.googlesource.com/17745
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Analogous to https://go-review.googlesource.com/#/c/8457/ this
code synthesizes an set of program arguments for Android on the
arm64 architecture.
Change-Id: I851958b4b0944ec79d7a1426a3bb2cfc31746797
Reviewed-on: https://go-review.googlesource.com/17782
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Otherwise it's hard to tell the difference between
link1 and link2 or other tests.
Change-Id: I36c153cccb10959535595938dfbc49db930b9fac
Reviewed-on: https://go-review.googlesource.com/17851
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Updates bundled copy of x/net/http2 to include
https://golang.org/cl/17823 (catching panics in Handlers)
Fixes#13555
Change-Id: I08e4e38e736a8d93f5ec200e8041c143fc6eafce
Reviewed-on: https://go-review.googlesource.com/17824
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Use two internal representations for Float values (similar to what is done
for Int values). Transparently switch to a big.Float representation when
big.Rat values become unwieldy. This is almost never needed for real-world
programs but it is trivial to create test cases that cannot be handled with
rational arithmetic alone.
As a consequence, the go/constant API semantics changes slightly: Until now,
a value could always be represented in its "smallest" form (e.g., float values
that happened to be integers would be represented as integers). Now, constant
Kind depends on how the value was created, rather than its actual value. (The
reason why we cannot automatically "normalize" values to their smallest form
anymore is because floating-point numbers are not exact in general; and thus
normalization is often not possible in the first place, or would throw away
precision when it is not desired.) This has repercussions as to how constant
Values are used go/types and required corresponding adjustments.
Details of the changes:
go/constant package:
- use big.Rat and big.Float values to represent floating-point values
(internal change)
- changed semantic of Value.Kind accordingly
- String now returns a short, human-readable form of a value
(this leads to better error messages in go/types)
- added ToInt, ToFloat, and ToComplex conversion functions
- added ExactString to obtain an exact string form of a value
go/types:
- adjusted and simplified implementation of representableConst
- adjusted various places where Value.Kind was expected to be "smallest"
by calling the respective ToInt/Float/Complex conversion functions
- enabled 5 disabled tests in stdlib_test.go that now work
api checker:
- print all constant values in a short human-readable form (floats are
printed in floating-point form), but also print an exact form if it
is different from the short form
- adjusted test golden file and go.1.1.text reference file
Fixes#11327.
Change-Id: I492b704aae5b0238e5b7cee13e18ffce61193587
Reviewed-on: https://go-review.googlesource.com/17360
Reviewed-by: Alan Donovan <adonovan@google.com>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This CL also updates the bundled http2 package with the h2 fix from
https://golang.org/cl/17757Fixes#13159
Change-Id: If0e3b4bd04d0dceed67d1b416ed838c9f1961576
Reviewed-on: https://go-review.googlesource.com/17758
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>