It shouldn't semacquire() inside an acquirem(), the runtime
thinks that means deadlock. It actually isn't a deadlock, but it
looks like it because acquirem() does m.locks++.
Candidate for inclusion in 1.4.1. runtime.Stack with all=true
is pretty unuseable in GOMAXPROCS>1 environment.
fixes#9321
Change-Id: Iac6b664217d24763b9878c20e49229a1ecffc805
Reviewed-on: https://go-review.googlesource.com/1600
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Make sure dequeueing from a channel queue does not exhibit quadratic time behavior.
Change-Id: Ifb7c709b026f74c7e783610d4914dd92909a441b
Reviewed-on: https://go-review.googlesource.com/1212
Reviewed-by: Russ Cox <rsc@golang.org>
Usage:
fibo <n> compute fibonacci(n), n must be >= 0
fibo -bench benchmark fibonacci computation (takes about 1 min)
Additional flags:
-half add values using two half-digit additions
-opt optimize memory allocation through reuse
-short only print the first 10 digits of very large fibonacci numbers
This change was reviewed in detail as https://codereview.appspot.com/168480043 .
Change-Id: I7c86d49c5508532ea6206d00f424cf2117d2fe41
Reviewed-on: https://go-review.googlesource.com/1211
Reviewed-by: Russ Cox <rsc@golang.org>
When we start work on Gerrit, ppc64 and garbage collection
work will continue in the master branch, not the dev branches.
(We may still use dev branches for other things later, but
these are ready to be merged, and doing it now, before moving
to Git means we don't have to have dev branches working
in the Gerrit workflow on day one.)
TBR=rlh
CC=golang-codereviews
https://golang.org/cl/183140043
640 bytes ought to be enough for anybody.
We'll bring this back down before Go 1.5. That's issue 9214.
TBR=rlh
CC=golang-codereviews
https://golang.org/cl/188730043
The SudoG used to sit on the stack, so it was cheap to allocated
and didn't need to be cleaned up when finished.
For the conversion to Go, we had to move sudog off the stack
for a few reasons, so we added a cache of recently used sudogs
to keep allocation cheap. But we didn't add any of the necessary
cleanup before adding a SudoG to the new cache, and so the cached
SudoGs had stale pointers inside them that have caused all sorts
of awful, hard to debug problems.
CL 155760043 made sure SudoG.elem is cleaned up.
CL 150520043 made sure SudoG.selectdone is cleaned up.
This CL makes sure SudoG.next, SudoG.prev, and SudoG.waitlink
are cleaned up. I should have done this when I did the other two
fields; instead I wasted a week tracking down a leak they caused.
A dangling SudoG.waitlink can point into a sudogcache list that
has been "forgotten" in order to let the GC collect it, but that
dangling .waitlink keeps the list from being collected.
And then the list holding the SudoG with the dangling waitlink
can find itself in the same situation, and so on. We end up
with lists of lists of unusable SudoGs that are still linked into
the object graph and never collected (given the right mix of
non-trivial selects and non-channel synchronization).
More details in golang.org/issue/9110.
Fixes#9110.
LGTM=r
R=r
CC=dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/177870043
This is to reduce the delta between dev.cc and dev.garbage to just garbage collector changes.
These are the files that had merge conflicts and have been edited by hand:
malloc.go
mem_linux.go
mgc.go
os1_linux.go
proc1.go
panic1.go
runtime1.go
LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/174180043
Now the only difference between dev.cc and dev.garbage
is the runtime conversion on the one side and the
garbage collection on the other. They both have the
same set of changes from default and dev.power64.
LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/172570043
The remaining run-only tests will be migrated to run.go in another CL.
This CL will break the build due to issues 8746 and 8806.
Update #4139
Update #8746
Update #8806
LGTM=rsc
R=rsc, bradfitz, iant
CC=golang-codereviews
https://golang.org/cl/144630044
Now each C printf, Go print, or Go println is guaranteed
not to be interleaved with other calls of those functions.
This should help when debugging concurrent failures.
LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/169120043
One failing case this removes is:
var bytes = []byte("hello, world")
var copy_bytes = bytes
We could handle this in the compiler, but it requires special
case for a variable that is initialized to the value of a
variable that is initialized to a string literal converted to
[]byte. This seems an unlikely case--it never occurs in the
standrd library--and it seems unnecessary to write the code to
handle it.
If we do want to support this case, one approach is
https://golang.org/cl/171840043.
The other failing cases are of the form
var bx bool
var copy_bx = bx
The compiler used to initialize copy_bx to false. However,
that led to issue 7665, since bx may be initialized in non-Go
code. The compiler no longer assumes that bx must be false,
so copy_bx can not be statically initialized.
We can fix these with https://golang.org/cl/169040043
if we also pass -complete to the compiler as part of this
test. This is OK but it's too late in the release cycle.
Fixes#8746.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/165400043
On power64x, this one line in live.go reports that t is live
because of missing optimization passes. This isn't what this
test is trying to test, so shuffle bad40 so that it still
accomplishes the intent of the test without also depending on
optimization.
LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/167110043
The remaining failures in this test are because of incomplete
optimization support on power64x. Tracked in issue 9058.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/168130043
All three cases of clearfat were wrong on power64x.
The cases that handle 1032 bytes and up and 32 bytes and up
both use MOVDU (one directly generated in a loop and the other
via duffzero), which leaves the pointer register pointing at
the *last written* address. The generated code was not
accounting for this, so the byte fill loop was re-zeroing the
last zeroed dword, rather than the bytes following the last
zeroed dword. Fix this by simply adding an additional 8 byte
offset to the byte zeroing loop.
The case that handled under 32 bytes was also wrong. It
didn't update the pointer register at all, so the byte zeroing
loop was simply re-zeroing the beginning of region. Again,
the fix is to add an offset to the byte zeroing loop to
account for this.
LGTM=dave, bradfitz
R=rsc, dave, bradfitz
CC=golang-codereviews
https://golang.org/cl/168870043
Originally traceback was only used for printing the stack
when an unexpected signal came in. In that case, the
initial PC is taken from the signal and should be used
unaltered. For the callers, the PC is the return address,
which might be on the line after the call; we subtract 1
to get to the CALL instruction.
Traceback is now used for a variety of things, and for
almost all of those the initial PC is a return address,
whether from getcallerpc, or gp->sched.pc, or gp->syscallpc.
In those cases, we need to subtract 1 from this initial PC,
but the traceback code had a hard rule "never subtract 1
from the initial PC", left over from the signal handling days.
Change gentraceback to take a flag that specifies whether
we are tracing a trap.
Change traceback to default to "starting with a return PC",
which is the overwhelmingly common case.
Add tracebacktrap, like traceback but starting with a trap PC.
Use tracebacktrap in signal handlers.
Fixes#7690.
LGTM=iant, r
R=r, iant
CC=golang-codereviews
https://golang.org/cl/167810044
The test just doubled a certain number of times
and then gave up. On a mostly fast but occasionally
slow machine this may never make the test run
long enough to see the linear growth.
Change test to keep doubling until the first round
takes at least a full second, to reduce the effect of
occasional scheduling or other jitter.
The failure we saw had a time for the first round
of around 100ms.
Note that this test still passes once it sees a linear
effect, even with a very small total time.
The timeout here only applies to how long the execution
must be to support a reported failure.
LGTM=khr
R=khr
CC=golang-codereviews, rlh
https://golang.org/cl/164070043
This brings dev.power64 up-to-date with the current tip of
default. go_bootstrap is still panicking with a bad defer
when initializing the runtime (even on amd64).
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/152570049
This also removes pkg/runtime/traceback_lr.c, which was ported
to Go in an earlier commit and then moved to
runtime/traceback.go.
Reviewer: rsc@golang.org
rsc: LGTM
test16 used to fail with gccgo. The withoutRecoverRecursive
test would have failed in some possible implementations.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/151630043
This brings cmd/gc in line with the spec on this question.
It might break existing code, but that code was not conformant
with the spec.
Credit to Rémy for finding the broken code.
Fixes#6366.
LGTM=r
R=golang-codereviews, r
CC=adonovan, golang-codereviews, gri
https://golang.org/cl/129550043
https://golang.org/cl/152700045/ made it possible for struct literals assigned to globals to use <N> as the RHS. Normally, this is to zero out variables on first use. Because globals are already zero (or their linker initialized value), we just ignored this.
Now that <N> can occur from non-initialization code, we need to emit this code. We don't use <N> for initialization of globals any more, so this shouldn't cause any excessive zeroing.
Fixes#8961.
LGTM=rsc
R=golang-codereviews, rsc
CC=bradfitz, golang-codereviews
https://golang.org/cl/154540044
This fixes the bug in which the linker reports "missing Go
type information" when a -X option refers to a symbol that is
not used.
Fixes#8821.
LGTM=rsc
R=rsc, r
CC=golang-codereviews
https://golang.org/cl/151000043
If there is a leading ·, assume there is a Go prototype and
attach the Go prototype information to the function.
If the function is not called from Go and does not need a
Go prototype, it can be made file-local instead (using name<>(SB)).
This fixes the current BSD build failures, by giving functions like
sync/atomic.StoreUint32 argument stack map information.
Fixes#8753.
LGTM=khr, iant
R=golang-codereviews, iant, khr, bradfitz
CC=golang-codereviews, r, rlh
https://golang.org/cl/142150043
iterdelete's run time varies; occasionally we get unlucky. To reduce spurious failures, average away some of the variation.
On my machine, 8 of 5000 runs (0.15%) failed before this CL. After this CL, there were no failures after 35,000 runs.
I confirmed that this adjusted test still fails before CL 141270043.
LGTM=khr
R=khr
CC=bradfitz, golang-codereviews
https://golang.org/cl/140610043
