The ARM implementation of runtime.cgocallback_gofunc diverged
from the calling convention by leaving a word of garbage at
the top of the stack and storing the return PC above the
locals. This change stores the return PC at the top of the
stack and removes the save area above the locals.
Update #5124
This CL fixes first part of the ARM issues and added the unwind test.
R=golang-dev, bradfitz, minux.ma, cshapiro, rsc
CC=golang-dev
https://golang.org/cl/7728045
Adds the new debugging constant 'checkgc'. If its value is non-zero
all calls to mallocgc() from hashmap.c will start a garbage collection.
Fixes#5074.
R=golang-dev, khr
CC=golang-dev, rsc
https://golang.org/cl/7663051
Fixes performance of the current windows network poller
with the new scheduler.
Gives runtime a hint when GetQueuedCompletionStatus() will block.
Fixes#5068.
benchmark old ns/op new ns/op delta
BenchmarkTCP4Persistent 4004000 33906 -99.15%
BenchmarkTCP4Persistent-2 21790 17513 -19.63%
BenchmarkTCP4Persistent-4 44760 34270 -23.44%
BenchmarkTCP4Persistent-6 45280 43000 -5.04%
R=golang-dev, alex.brainman, coocood, rsc
CC=golang-dev
https://golang.org/cl/7612045
I'm not sure how to write a test for this. The change in
behaviour is that if you somehow get a SIGBUS signal for an
address >= 0x1000, the program will now crash rather than
calling panic. As far as I know, on x86 GNU/Linux, the only
way to get a SIGBUS (rather than a SIGSEGV) is to set the
stack pointer to an invalid value.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/7906045
On Darwin and FreeBSD, the mmap syscall return value is returned
unmodified. This means that the return value will either be a
valid address or a positive error number.
Also check return value from mmap in SysReserve - the callers of
SysReserve expect nil to be returned if the allocation failed.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7871043
Rather than just checking for ENOMEM, check for a return value of less
than 4096, so that we catch other errors such as EACCES and EINVAL.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7942043
Fixes#5061.
Current code relies on the fact that fd's are automatically removed from epoll set when closed. However, it is not true. Underlying file description is removed from epoll set only when *all* fd's referring to it are closed.
There are 2 bad consequences:
1. Kernel delivers notifications on already closed fd's.
2. The following sequence of events leads to error:
- add fd1 to epoll
- dup fd1 = fd2
- close fd1 (not removed from epoll since we've dup'ed the fd)
- dup fd2 = fd1 (get the same fd as fd1)
- add fd1 to epoll = EEXIST
So, if fd can be potentially dup'ed of fork'ed, it's necessary to explicitly remove the fd from epoll set.
R=golang-dev, bradfitz, dave
CC=golang-dev
https://golang.org/cl/7870043
Add missing CLOSUREVAR in switch.
Mark MAKE, string conversion nodes as impossible.
Control statements do not need instrumentation.
Instrument COM and LROT nodes.
Instrument map length.
Update #4228
R=dvyukov, golang-dev
CC=golang-dev
https://golang.org/cl/7504047
Hashtable is arranged as an array of
8-entry buckets with chained overflow.
Each bucket has 8 extra hash bits
per key to provide quick lookup within
a bucket. Table is grown incrementally.
Update #3885
Go time drops from 0.51s to 0.34s.
R=r, rsc, m3b, dave, bradfitz, khr, ugorji, remyoudompheng
CC=golang-dev
https://golang.org/cl/7504044
Inserting a key-value pair into a hashmap storing keys or values
indirectly can cause the garbage collector to find the hashmap in
an inconsistent state.
Fixes#5074.
R=golang-dev, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/7913043
On NetBSD tv_sec is already an int64 so no need for a test.
On OpenBSD, semasleep expects a Unix time as argument,
and 1<<30 is in 2004.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7810044
The current SysAlloc implementation suffers from a signed vs unsigned
comparision bug. Since the error code from mmap is negated, the
unsigned comparision of v < 4096 is always false on error. Fix this
by switching to the darwin/freebsd/linux mmap model and leave the mmap
return value unmodified.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/7870044
This provides a way to generate core dumps when people need them.
The settings are:
GOTRACEBACK=0 no traceback on panic, just exit
GOTRACEBACK=1 default - traceback on panic, then exit
GOTRACEBACK=2 traceback including runtime frames on panic, then exit
GOTRACEBACK=crash traceback including runtime frames on panic, then crash
Fixes#3257.
R=golang-dev, devon.odell, r, daniel.morsing, ality
CC=golang-dev
https://golang.org/cl/7666044
NEGL does a negation of the bottom 32 bits and then zero-extends to 64 bits,
resulting in a negative 32-bit number but a positive 64-bit number.
NEGQ does a full 64-bit negation, so that the result is negative both as
a 32-bit and as a 64-bit number.
This doesn't matter for the functions that are declared to return int32.
It only matters for the ones that return int64 or void* [sic].
This will fix the current incorrect error in the OpenBSD/amd64 build.
The build will still be broken, but it won't report a bogus error.
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7536046
Bring net/fd_linux.go back (it was deleted this morning)
because it is still needed for ARM.
Fix a few typos in the runtime reorg.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/7759046
thread_GOOS.c becomes os_GOOS.c.
signal_GOOS_GOARCH.c becomes os_GOOS_GOARCH.c,
but with non-GOARCH-specific code moved into os_GOOS.c.
The actual arch-specific signal handler moves into signal_GOARCH.c
to avoid per-GOOS duplication.
New files signal_GOOS_GOARCH.h provide macros for
accessing fields of the very system-specific signal info structs.
Lots moving, but nothing changing.
This is a preliminarly cleanup so I can work on the signal
handling code to fix some open issues without having to
make each change 13 times.
Tested on Linux and OS X, 386 and amd64.
Will fix Plan 9, Windows, and ARM after the fact if necessary.
(Plan 9 and Windows should be fine; ARM will probably have some typos.)
Net effect: -1081 lines of code.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/7565048
With the global redefinition of runtime·open by CL 7543043,
we need to provide a third argument and remove the cast
to the string.
Fixes build on 386 version of Plan 9.
R=khr, rsc, rminnich, ality
CC=golang-dev
https://golang.org/cl/7644047
Uses AES hardware instructions on 386/amd64 to implement
a fast hash function. Incorporates a random key to
thwart hash collision DOS attacks.
Depends on CL#7548043 for new assembly instructions.
Update #3885
Helps some by making hashing faster. Go time drops from
0.65s to 0.51s.
R=rsc, r, bradfitz, remyoudompheng, khr, dsymonds, minux.ma, elias.naur
CC=golang-dev
https://golang.org/cl/7543043
The issue was that scvg is assigned *after* the scavenger goroutine is started,
so when the scavenger calls entersyscall() the g==scvg check can fail.
Fixes#5025.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7629045
The problem is that there are lots of dead G's from previous tests,
each dead G consumes 1 stack segment.
Fixes#5034.
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7749043
The call to the C function runtime.findnull() requires
that we provide the argument at 0(SP).
R=rsc, rminnich, ality
CC=golang-dev
https://golang.org/cl/7559047
Otherwise the next goroutine run on the m
can get inadvertently locked if it executes a cgo call
that turns on the internal lock.
While we're here, fix the cgo panic unwind to
decrement m->ncgo like the non-panic unwind does.
Fixes#4971.
R=golang-dev, iant, dvyukov
CC=golang-dev
https://golang.org/cl/7627043
Now the default startup is that the program begins at _rt0_386_$GOOS,
which behaves as if calling main(argc, argv). Main jumps to _rt0_386.
This makes the _rt0_386 entry match the expected semantics for
the standard C "main" function, which we can now provide for use when
linking against a standard C library.
386 analogue of https://golang.org/cl/7525043
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/7551045
Change 231af8ac63aa (CL 7314062) made runtime.enteryscall()
set m->mcache = nil, which means that we can no longer use
syscall.errstr in syscall.Syscall and syscall.Syscall6, since it
requires a new buffer to be allocated for holding the error string.
Instead, we use pre-allocated per-M storage to hold error strings
from syscalls made while in entersyscall mode, and call
runtime.findnull to calculate the lengths.
Fixes#4994.
R=rsc, rminnich, ality, dvyukov, rminnich, r
CC=golang-dev
https://golang.org/cl/7567043
The deadlock episodically occurs on misc/cgo/test/TestCthread.
The problem is that starttheworld() leaves some P's with local work
without M's. Then all active M's enter into syscalls, but reject to
wake another M's due to the following check (both in entersyscallblock() and in retake()):
if(p->runqhead == p->runqtail &&
runtime·atomicload(&runtime·sched.nmspinning) +
runtime·atomicload(&runtime·sched.npidle) > 0)
continue;
R=rsc
CC=golang-dev
https://golang.org/cl/7424054
Still to do: non-linux and non-amd64.
It may work on other ELF-based amd64 systems too, but untested.
"go test -ldflags -hostobj $GOROOT/misc/cgo/test" passes.
Much may yet change, but this seems a reasonable checkpoint.
R=iant
CC=golang-dev
https://golang.org/cl/7369057
Now the default startup is that the program begins at _rt0_amd64_$GOOS,
which sets DI = argc, SI = argv and jumps to _rt0_amd64.
This makes the _rt0_amd64 entry match the expected semantics for
the standard C "main" function, which we can now provide for use when
linking against a standard C library.
R=golang-dev, devon.odell, minux.ma
CC=golang-dev
https://golang.org/cl/7525043
broke arm garbage collector
traceback_arm fails with a missing pc. It needs CL 7494043.
But that only makes the build break later, this time with
"invalid freelist". Roll back until it can be fixed correctly.
««« original CL description
runtime: restrict stack root scan to locals and arguments
R=rsc
CC=golang-dev
https://golang.org/cl/7301062
»»»
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7493044
If the constant CollectStats is non-zero and GOGCTRACE=1
the garbage collector will print basic statistics about executed
GC instructions.
R=golang-dev, dvyukov
CC=golang-dev, rsc
https://golang.org/cl/7413049
Fixes#4904.
The problem was that when the test runs the heap had grown to ~100MB,
so GC allows it to grow to 200MB, and so the test fails.
Moving the test to a separate process makes it much more isolated and stable.
R=golang-dev, minux.ma
CC=golang-dev
https://golang.org/cl/7441046
Also make the crossover point an architecture-dependent constant,
although it's the same everywhere for now.
BenchmarkAppendStr1Byte 416 145 -65.14%
BenchmarkAppendStr4Bytes 743 217 -70.79%
BenchmarkAppendStr8Bytes 421 270 -35.87%
BenchmarkAppendStr16Bytes 415 403 -2.89%
BenchmarkAppendStr32Bytes 415 391 -5.78%
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7459044
Putting the M initialization in multiple places will not scale.
Various code assumes mstart is the start already. Make it so.
R=golang-dev, devon.odell
CC=golang-dev
https://golang.org/cl/7420048
There is a #pragma dynexport crosscall2, to help SWIG,
and 6l cannot export the symbol if it doesn't get to see it.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7448044
There are some function pointers declared by 6c in
package runtime without initialization and then also
declared in package runtime/cgo with initialization,
so that if runtime/cgo is linked in, the function pointers
are non-nil, and otherwise they are nil. We depend on
this property for implementing non-essential cgo hooks
in package runtime.
The declarations in package runtime are 6c-compiled
and end up in .6 files. The declarations in package runtime/cgo
are gcc-compiled and end up in .o files. Since 6l links the .6
and .o files together, this all works.
However, when we switch to "external linking" mode,
6l will not see the .o files, and it would be up to the host linker
to resolve the two into a single initialized symbol.
Not all host linkers will do this (in particular OS X gcc will not).
To fix this, move the cgo declarations into 6c-compiled code,
so that they end up in .6 files, so that 6l gets them no matter what.
R=golang-dev
CC=golang-dev
https://golang.org/cl/7440045
The naming in this package is a disaster.
Make it all consistent.
Remove some 'static' from functions that will
be referred to from other files soon.
This CL is purely renames using global search and replace.
Submitting separately so that real changes will not
be drowned out by these renames in future CLs.
TBR=iant
CC=golang-dev
https://golang.org/cl/7416046
runtime: double-check that symbol table is sorted
If the symbol table is unsorted, the binary search in findfunc
will not find its func, which will make stack traces stop early.
When the garbage collector starts using the stack tracer,
that would be a serious problem.
The unsorted symbol addresses came from from two things:
1. The symbols in an ELF object are not necessarily sorted,
so sort them before adding them to the symbol list.
2. The __i686.get_pc_thunk.bx symbol is present in multiple
object files and was having its address adjusted multiple
times, producing an incorrect address in the symbol table.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7440044
Revision 6a88e1893941 corrupts the argument to
racefuncenter by pushing the data block pointer
to the stack.
Fixes#4885.
R=dvyukov, rsc
CC=golang-dev
https://golang.org/cl/7381053
add per-P cache of dead G's
add global runnable queue (not used for now)
add list of idle P's (not used for now)
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7397061
