We're going to need a different TLS offset for Android Q, so the static
offsets used for 386 and amd64 are no longer viable on Android.
Introduce runtime·tls_g and use that for indexing into TLS storage. As
an added benefit, we can then merge the TLS setup code for all android
GOARCHs.
While we're at it, remove a bunch of android special cases no longer
needed.
Updates #29674
Updates #29249 (perhaps fixes it)
Change-Id: I77c7385aec7de8f1f6a4da7c9c79999157e39572
Reviewed-on: https://go-review.googlesource.com/c/go/+/169817
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
The specialized functions set up the g register using the pthread
API instead of setg_gcc, but the inittls functions have already
made sure setg_gcc works.
Updates #29674
Change-Id: Ie67c068d638af8b5823978ee839f6b61b2228996
Reviewed-on: https://go-review.googlesource.com/c/go/+/169797
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Add TSAN acquire/release calls to runtime/cgo to match the ones
generated by cgo. This avoids a false positive race around the malloc
memory used in runtime/cgo when other goroutines are simultaneously
calling malloc and free from cgo.
These new calls will only be used when building with CGO_CFLAGS and
CGO_LDFLAGS set to -fsanitize=thread, which becomes a requirement to
avoid all false positives when using TSAN. These are needed not just
for runtime/cgo, but also for any runtime package that uses cgo (such as
net and os/user).
Add an unused attribute to the _cgo_tsan_acquire and _cgo_tsan_release
functions, in case there are no actual cgo function calls.
Add a test that checks that setting CGO_CFLAGS/CGO_LDFLAGS avoids a
false positive report when using os/user.
Change-Id: I0905c644ff7f003b6718aac782393fa219514c48
Reviewed-on: https://go-review.googlesource.com/23492
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Before, those C files might have been intended for the Plan 9 C compiler,
but that option was removed in Go 1.5. We can simplify the maintenance
of cgo packages now if we assume C files (and C++ and M and SWIG files)
should only be considered when cgo is enabled.
Also remove newly unnecessary build tags in runtime/cgo's C files.
Fixes#14123
Change-Id: Ia5a7fe62b9469965aa7c3547fe43c6c9292b8205
Reviewed-on: https://go-review.googlesource.com/19613
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is a subset of https://golang.org/cl/20022 with only the copyright
header lines, so the next CL will be smaller and more reviewable.
Go policy has been single space after periods in comments for some time.
The copyright header template at:
https://golang.org/doc/contribute.html#copyright
also uses a single space.
Make them all consistent.
Change-Id: Icc26c6b8495c3820da6b171ca96a74701b4a01b0
Reviewed-on: https://go-review.googlesource.com/20111
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Android linker does not handle TLS for us. We set up the TLS slot
for g, as darwin/386,amd64 handle instead. This is disgusting and
fragile. We will eventually fix this ugly hack by taking advantage
of the recent TLS IE model implementation. (Instead of referencing
an GOT entry, make the code sequence look into the TLS variable that
holds the offset.)
The TLS slot for g in android/amd64 assumes a fixed offset from %fs.
See runtime/cgo/gcc_android_amd64.c for details.
For golang/go#10743
Change-Id: I1a3fc207946c665515f79026a56ea19134ede2dd
Reviewed-on: https://go-review.googlesource.com/15991
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The memory sanitizer (msan) is a nice compiler feature that can
dynamically check for memory errors in C code. It's not useful for Go
code, since Go is memory safe. But it is useful to be able to use the
memory sanitizer on C code that is linked into a Go program via cgo.
Without this change it does not work, as msan considers memory passed
from Go to C as uninitialized.
To make this work, change the runtime to call the C mmap function when
using cgo. When using msan the mmap call will be intercepted and marked
as returning initialized memory.
Work around what appears to be an msan bug by calling malloc before we
call mmap.
Change-Id: I8ab7286d7595ae84782f68a98bef6d3688b946f9
Reviewed-on: https://go-review.googlesource.com/15170
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Commit to stack copying for stack growth.
We're carrying around a surprising amount of cruft from older schemes.
I am confident that precise stack scans and stack copying are here to stay.
Delete fallback code for when precise stack info is disabled.
Delete fallback code for when copying stacks is disabled.
Delete fallback code for when StackCopyAlways is disabled.
Delete Stktop chain - there is only one stack segment now.
Delete M.moreargp, M.moreargsize, M.moreframesize, M.cret.
Delete G.writenbuf (unrelated, just dead).
Delete runtime.lessstack, runtime.oldstack.
Delete many amd64 morestack variants.
Delete initialization of morestack frame/arg sizes (shortens split prologue!).
Replace G's stackguard/stackbase/stack0/stacksize/
syscallstack/syscallguard/forkstackguard with simple stack
bounds (lo, hi).
Update liblink, runtime/cgo for adjustments to G.
LGTM=khr
R=khr, bradfitz
CC=golang-codereviews, iant, r
https://golang.org/cl/137410043
