Request ID reuse is allowed by the FastCGI spec [1]. In particular nginx uses
the same request ID, 1, for all requests on a given connection. Because
serveRequest does not remove the request from conn.requests, this causes it to
treat the second request as a duplicate and drops the connection immediately
after beginRequest. This manifests with nginx option 'fastcgi_keep_conn on' as
the following message in nginx error log:
2014/03/17 01:39:13 [error] 730#0: *109 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: x.x.x.x, server: example.org, request: "GET / HTTP/1.1", upstream: "fastcgi://127.0.0.1:9001", host: "example.org"
Because handleRecord and serveRequest run in different goroutines, access to
conn.requests must now be synchronized.
[1] http://www.fastcgi.com/drupal/node/6?q=node/22#S3.3
LGTM=bradfitz
R=bradfitz
CC=golang-codereviews
https://golang.org/cl/76800043
I believe the original author of this code just forgot to check for error here.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/76760043
"env" is a valid go command. This patch is to make bash to autocomplete it.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/74660045
Smooth out the setup process for new contributors.
* Remove references $GOROOT (often not defined).
* Add a note for contributing to subrepositories.
* Emphasize that hg mail also uploads the latest copy.
LGTM=adg
R=golang-codereviews, iant, adg
CC=golang-codereviews
https://golang.org/cl/74370043
It was using the wrong offset and returned random values
making "runoutput" compiler tests crash.
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/76250043
They were rejected by NaCl due to AES instructions and
accesses to %gs:0x8, caused by wrong tlsoffset value.
LGTM=iant
R=rsc, dave, iant
CC=golang-codereviews
https://golang.org/cl/76050044
It's possible that bgsweep constantly does not catch up for some reason,
in this case runfinq was not woken at all.
R=rsc
CC=golang-codereviews
https://golang.org/cl/75940043
The problem was that spans end up in wrong lists after split
(e.g. in h->busy instead of h->central->empty).
Also the span can be non-swept before split,
I don't know what it can cause, but it's safer to operate on swept spans.
Fixes#7544.
R=golang-codereviews, rsc
CC=golang-codereviews, khr
https://golang.org/cl/76160043
Currently processes crash with obscure message.
Say that it's "out of memory".
LGTM=rsc
R=golang-codereviews
CC=golang-codereviews, khr, rsc
https://golang.org/cl/75820045
Old versions of DTrace (as those shipped in OS X and FreeBSD)
don't support unicode characters in symbol names. Replace '·'
to '.' to make DTrace happy.
Fixes#7493
LGTM=aram, rsc
R=aram, rsc, gobot, iant
CC=golang-codereviews
https://golang.org/cl/72280043
The Solaris network poller uses event ports, which are
level-triggered. As such, it has to re-arm itself after each
wakeup. The arming mechanism (which runs in its own thread) raced
with the closing of a file descriptor happening in a different
thread. When a network file descriptor is about to be closed,
the network poller is awaken to give it a chance to remove its
association with the file descriptor. Because the poller always
re-armed itself, it raced with code that closed the descriptor.
This change makes the network poller check before re-arming if
the file descriptor is about to be closed, in which case it will
ignore the re-arming request. It uses the per-PollDesc lock in
order to serialize access to the PollDesc.
This change also adds extensive documentation describing the
Solaris implementation of the network poller.
Fixes#7410.
LGTM=dvyukov, iant
R=golang-codereviews, bradfitz, iant, dvyukov, aram.h, gobot
CC=golang-codereviews
https://golang.org/cl/69190044
debug/elf does the same thing, use []byte{} for
any missing sections.
Fixes#7510
LGTM=rsc
R=golang-codereviews, iant
CC=golang-codereviews, rsc
https://golang.org/cl/75230043
Mark free memory blocks as unused.
On amd64 it allows the process to eat all 128 GB of heap
without killing the machine.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/74070043
This is especially important for SetPanicOnCrash,
but also useful for e.g. nil deref in mallocgc.
Panics on such crashes can't lead to anything useful,
only to deadlocks, hangs and obscure crashes.
This is a copy of broken but already LGTMed
https://golang.org/cl/68540043/
TBR=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/75320043
When we copy stack, we check only new size of the top segment.
This is incorrect, because we can have other segments below it.
LGTM=khr
R=golang-codereviews, khr
CC=golang-codereviews, rsc
https://golang.org/cl/73980045
Calling runtime·cgocall could trigger a GC in the child while
gclock was held by the parent.
Fixes#7511
LGTM=bradfitz, dvyukov, dave
R=golang-codereviews, bradfitz, dvyukov, dave
CC=golang-codereviews, rsc
https://golang.org/cl/75210044
The lowering to runtime calls introduces hidden pointers to the
arguments of select clauses. When implicit conversions were
involved it could end up with incompatible pointers. Since the
pointed-to types have the same representation, we can introduce a
forced conversion.
Fixes#6847.
LGTM=rsc
R=rsc, iant, khr
CC=golang-codereviews
https://golang.org/cl/72380043
It was using a REP STOSQ but putting in CX the number of 32-bit
words to clear.
LGTM=dave
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/75240043
Under some circumstances, gccgoToolchain's ld can pass the path of
build outputs that have been deleted to the link command.
Fixes#7303.
LGTM=rsc
R=golang-codereviews, dave, michael.hudson, rsc
CC=golang-codereviews
https://golang.org/cl/61970044
The compilers expect to not be interrupted by floating
point exceptions. On Plan 9, every process starts with
interrupts enabled for invalid operation, stack overflow,
and divide by zero exceptions.
LGTM=rsc
R=rsc, 0intro
CC=golang-codereviews
https://golang.org/cl/72750043
Previously, we wrote "kill" to the process control file
to kill a program. This is problematic because it doesn't
let the program gracefully exit.
This matters especially if the process we're killing is a
Go program. On Unix, sending SIGKILL to a Go program will
automatically kill all runtime threads. On Plan 9, there
are no threads so when the program wants to exit it has to
somehow signal all of the runtime processes. It can't do
this if we mercilessly kill it by writing to it's control
file.
Instead, we now send it a note to invoke it's note handler
and let it perform any cleanup before exiting.
LGTM=rsc
R=rsc, 0intro
CC=golang-codereviews
https://golang.org/cl/74440044
On Plan 9, the kernel disallows the use of floating point
instructions while handling a note. Previously, we worked
around this by using a simple loop in place of memmove.
When I added that work-around, I verified that all paths
from the note handler didn't end up calling memmove. Now
that memclr is using SSE instructions, the same process
will have to be done again.
Instead of doing that, however, this CL just punts and
uses unoptimized functions everywhere on Plan 9.
LGTM=rsc
R=rsc, 0intro
CC=golang-codereviews
https://golang.org/cl/73830044
Acid can't produce a stack trace without .frame symbols.
Of course, it can only unwind through linear stacks but
this is still better than nothing. (I wrote an acid func
to do the full unwind a long time ago but lost it and
haven't worked up the courage to write it again).
Note that these will only be present in the native symbol
table for Plan 9 binaries.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/72450045
syscall.naclWrite was missing from sys_nacl_386.s
This gets ./make.bash passing, but doesn't pass validation. I'm not sure if this is the fault of this change, or validation was broken anyway.
LGTM=rsc
R=minux.ma, rsc
CC=golang-codereviews
https://golang.org/cl/74510043
1. Fix the bug that shrinkstack returns memory to heap.
This causes growslice to misbehave (it manually initialized
blocks, and in efence mode shrinkstack's free leads to
partially-initialized blocks coming out of growslice.
Which in turn causes GC to crash while treating the garbage
as Eface/Iface.
2. Enable efence for stack segments.
LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews, khr
https://golang.org/cl/74080043
The garbage collector uses type information to guide the
traversal of the heap. If it sees a field that should be a string,
it marks the object pointed at by the string data pointer as
visited but does not bother to look at the data, because
strings contain bytes, not pointers.
If you save s[len(s):] somewhere, though, the string data pointer
actually points just beyond the string data; if the string data
were exactly the size of an allocated block, the string data
pointer would actually point at the next block. It is incorrect
to mark that next block as visited and not bother to look at
the data, because the next block may be some other type
entirely.
The fix is to ignore strings with zero length during collection:
they are empty and can never become non-empty: the base
pointer will never be used again. The handling of slices already
does this (but using cap instead of len).
This was not a bug in Go 1.2, because until January all string
allocations included a trailing NUL byte not included in the
length, so s[len(s):] still pointed inside the string allocation
(at the NUL).
This bug was causing the crashes in test/run.go. Specifically,
the parsing of a regexp in package regexp/syntax allocated a
[]syntax.Inst with rounded size 1152 bytes. In fact it
allocated many such slices, because during the processing of
test/index2.go it creates thousands of regexps that are all
approximately the same complexity. That takes a long time, and
test/run works on other tests in other goroutines. One such
other test is chan/perm.go, which uses an 1152-byte source
file. test/run reads that file into a []byte and then calls
strings.Split(string(src), "\n"). The string(src) creates an
1152-byte string - and there's a very good chance of it
landing next to one of the many many regexp slices already
allocated - and then because the file ends in a \n,
strings.Split records the tail empty string as the final
element in the slice. A garbage collection happens at this
point, the collection finds that string before encountering
the []syntax.Inst data it now inadvertently points to, and the
[]syntax.Inst data is not scanned for the pointers that it
contains. Each syntax.Inst contains a []rune, those are
missed, and the backing rune arrays are freed for reuse. When
the regexp is later executed, the runes being searched for are
no longer runes at all, and there is no match, even on text
that should match.
On 64-bit machines the pointer in the []rune inside the
syntax.Inst is larger (along with a few other pointers),
pushing the []syntax.Inst backing array into a larger size
class, avoiding the collision with chan/perm.go's
inadvertently sized file.
I expect this was more prevalent on OS X than on Linux or
Windows because those managed to run faster or slower and
didn't overlap index2.go with chan/perm.go as often. On the
ARM systems, we only run one errorcheck test at a time, so
index2 and chan/perm would never overlap.
It is possible that this bug is the root cause of other crashes
as well. For now we only know it is the cause of the test/run crash.
Many thanks to Dmitriy for help debugging.
Fixes#7344.
Fixes#7455.
LGTM=r, dvyukov, dave, iant
R=golang-codereviews, dave, r, dvyukov, delpontej, iant
CC=golang-codereviews, khr
https://golang.org/cl/74250043
Some of the errorcheck tests have many many identical regexps.
Use a map to avoid storing the compiled form many many times
in memory. Change the filterRe to a simple string to avoid
the expense of those regexps as well.
Cuts the time for run.go on index2.go by almost 50x.
Noticed during debugging of issue 7344.
LGTM=bradfitz
R=bradfitz, josharian
CC=golang-codereviews
https://golang.org/cl/74380043
debuglive >= 1 is not the condition under which we
start recording messages (we avoid printing for
init functions even if debuglive is set).
LGTM=bradfitz, iant
R=golang-codereviews, bradfitz
CC=golang-codereviews, iant, khr
https://golang.org/cl/74390043