On the machine I'm using, the hardware page size seems to be 64 kB.
Make ELF rounding and mmap quantum 64 kB to match.
Error numbers returned from kernel are positive; do not negate.
Implement stubs for math/big.
LGTM=minux
R=minux
CC=golang-codereviews
https://golang.org/cl/124300043
It can happen legitimately if a profiling signal arrives at just the wrong moment.
It's harmless.
Fixes#8153.
LGTM=minux
R=golang-codereviews, minux
CC=golang-codereviews, iant, r
https://golang.org/cl/118670043
Full spans can't be passed to UncacheSpan since we get rid of free.
LGTM=rsc
R=golang-codereviews
CC=golang-codereviews, khr, rsc
https://golang.org/cl/119490044
Instead of including <sys/types.h> to get size_t, instead include
the ISO C standard <stddef.h> header, which defines fewer additional
types at risk of colliding with the user code. In particular, this
prevents collisions between <sys/types.h>'s userspace definitions with
the kernel definitions needed by defs_linux.go.
Also, -cdefs mode uses #pragma pack, so we can keep misaligned fields.
Fixes#8477.
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/120610043
We call scanblock for lots of small root pieces
e.g. for every stack frame args and locals area.
Every scanblock invocation calls getempty/putempty,
which accesses lock-free stack shared among all worker threads.
One-element local cache allows most scanblock calls
to proceed without accessing the shared stack.
LGTM=rsc
R=golang-codereviews, rlh
CC=golang-codereviews, khr, rsc
https://golang.org/cl/121250043
We have an autogenerated version in zruntime_defs.
I am not sure what are the consequences as gdb never printed any values for me.
But it looks unnecessary to manually duplicate it.
LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews, iant, khr
https://golang.org/cl/115660043
For consistency with other code, as that was the only use of
memcopy outside of alg.goc.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/122030044
The gccgo version of USED only accepts a single variable, so
this simplifies merging.
LGTM=minux, dave
R=golang-codereviews, minux, dave
CC=golang-codereviews
https://golang.org/cl/115630043
A good cleanup anyway, and it makes some room for an additional
field needed for issue 8412.
Update #8412
LGTM=iant
R=iant, khr
CC=golang-codereviews
https://golang.org/cl/112700043
6a and 8a rearrange memmove such that the fallthrough from move_1or2 to move_0 ends up being a JMP to a RET. Insert an explicit RET to prevent such silliness.
Do the same for memclr as prophylaxis.
benchmark old ns/op new ns/op delta
BenchmarkMemmove1 4.59 4.13 -10.02%
BenchmarkMemmove2 4.58 4.13 -9.83%
LGTM=khr
R=golang-codereviews, dvyukov, minux, ruiu, bradfitz, khr
CC=golang-codereviews
https://golang.org/cl/120930043
Create proper closures so hash functions can be called
directly from Go. Rearrange calling convention so return
value is directly accessible.
LGTM=dvyukov
R=golang-codereviews, dvyukov, dave, khr
CC=golang-codereviews
https://golang.org/cl/119360043
Several reasons:
1. Significantly simplifies runtime.
2. This code proved to be buggy.
3. Free is incompatible with bump-the-pointer allocation.
4. We want to write runtime in Go, Go does not have free.
5. Too much code to free env strings on startup.
LGTM=khr
R=golang-codereviews, josharian, tracey.brendan, khr
CC=bradfitz, golang-codereviews, r, rlh, rsc
https://golang.org/cl/116390043
Stand-alone this test is fine. Run together with
others, however, the stack used can actually go
negative because other tests are freeing stack
during its execution.
This behavior is new with the new stack allocator.
The old allocator never returned (min-sized) stacks.
This test is fairly poor - it needs to run in
isolation to be accurate. Maybe we should delete it.
LGTM=r
R=r
CC=golang-codereviews
https://golang.org/cl/119330044
The DISPATCH and CALLFN macro definitions depend on an inconsistency
between the internal cpp mini-implementation and the language proper in
whether center-dot is an identifier character. The macro depends on it not
being an identifier character, but the resulting code depends on it being one.
Remove the dependence on the inconsistency by placing the center-dot into
the macro invocation rather that the body.
No semantic change. This is just renaming macro arguments.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/119320043
This change introduces gomallocgc, a Go clone of mallocgc.
Only a few uses have been moved over, so there are still
lots of uses from C. Many of these C uses will be moved
over to Go (e.g. in slice.goc), but probably not all.
What should remain of C's mallocgc is an open question.
LGTM=rsc, dvyukov
R=rsc, khr, dave, bradfitz, dvyukov
CC=golang-codereviews
https://golang.org/cl/108840046
Implement the design described in:
https://docs.google.com/document/d/1v4Oqa0WwHunqlb8C3ObL_uNQw3DfSY-ztoA-4wWbKcg/pub
Summary of the changes:
GC uses "2-bits per word" pointer type info embed directly into bitmap.
Scanning of stacks/data/heap is unified.
The old spans types go away.
Compiler generates "sparse" 4-bits type info for GC (directly for GC bitmap).
Linker generates "dense" 2-bits type info for data/bss (the same as stacks use).
Summary of results:
-1680 lines of code total (-1000+ in mgc0.c only)
-25% memory consumption
-3-7% binary size
-15% GC pause reduction
-7% run time reduction
LGTM=khr
R=golang-codereviews, rsc, christoph, khr
CC=golang-codereviews, rlh
https://golang.org/cl/106260045
Sweepone may be running while a new span is allocating. It
must not see the state updated while the sweepgen is unset.
Fixes#8399
LGTM=dvyukov
R=golang-codereviews, dvyukov
CC=golang-codereviews
https://golang.org/cl/118050043
Russ Cox
Shenghou Ma
Dmitriy Vyukov
Alex Brainman
Matthew Dempsky
Ian Lance Taylor
Keith Randall
Josh Bleecher Snyder
Rob Pike