All code in internal/runtime/syscall is Linux-specific, so better
move it to a new linux sub-directory. This way it will be easier
to factor out runtime syscall code from other platforms, e.g.
Windows.
Updates #51087.
Change-Id: Idd2a52444b33bf3ad576b47fd232e990cdc8ae75
Reviewed-on: https://go-review.googlesource.com/c/go/+/689155
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
This CL adds two related features enabled by default via compatibility
GODEBUGs containermaxprocs and updatemaxprocs.
On Linux, containermaxprocs makes the Go runtime consider cgroup CPU
bandwidth limits (quota/period) when setting GOMAXPROCS. If the cgroup
limit is lower than the number of logical CPUs available, then the
cgroup limit takes precedence.
On all OSes, updatemaxprocs makes the Go runtime periodically
recalculate the default GOMAXPROCS value and update GOMAXPROCS if it has
changed. If GOMAXPROCS is set manually, this update does not occur. This
is intended primarily to detect changes to cgroup limits, but it applies
on all OSes because the CPU affinity mask can change as well.
The runtime only considers the limit in the leaf cgroup (the one that
actually contains the process), caching the CPU limit file
descriptor(s), which are periodically reread for updates. This is a
small departure from the original proposed design. It will not consider
limits of parent cgroups (which may be lower than the leaf), and it will
not detection cgroup migration after process start.
We can consider changing this in the future, but the simpler approach is
less invasive; less risk to packages that have some awareness of runtime
internals. e.g., if the runtime periodically opens new files during
execution, file descriptor leak detection is difficult to implement in a
stable way.
For #73193.
Cq-Include-Trybots: luci.golang.try:gotip-linux-amd64-longtest
Change-Id: I6a6a636c631c1ae577fb8254960377ba91c5dc98
Reviewed-on: https://go-review.googlesource.com/c/go/+/670497
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Use the new SwissTable-based map in internal/runtime/maps as the basis
for the runtime map when GOEXPERIMENT=swissmap.
Integration is complete enough to pass all.bash. Notable missing
features:
* Race integration / concurrent write detection
* Stack-allocated maps
* Specialized "fast" map variants
* Indirect key / elem
For #54766.
Cq-Include-Trybots: luci.golang.try:gotip-linux-ppc64_power10,gotip-linux-amd64-longtest-swissmap
Change-Id: Ie97b656b6d8e05c0403311ae08fef9f51756a639
Reviewed-on: https://go-review.googlesource.com/c/go/+/594596
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Add internal/stringslite to the list of hard-coded package IDs to be
special cased in coverage package registration. This patch fixes
a new -coverpkg=all failure on the darwin longtest builders.
Change-Id: I56357572f215fab09f46226fe205924136322d9e
Reviewed-on: https://go-review.googlesource.com/c/go/+/601755
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Cleanup and friction reduction
For #65355.
Change-Id: Ia14c9dc584a529a35b97801dd3e95b9acc99a511
Reviewed-on: https://go-review.googlesource.com/c/go/+/600436
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@golang.org>
For #65355
Change-Id: I5fefe30dcb520159de565e61dafc74a740fc8730
Reviewed-on: https://go-review.googlesource.com/c/go/+/559715
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Add support to the runtime for registering coverage-instrumented
packages, using a new hook that can be called from the init function
of an instrumented package. The hook records the meta-data symbol for
the package (chaining it onto a list), and returns a package ID to be
used to identify functions in the package. This new hook is not yet
called; that will be added in a subsequent patch. The list of
registered meta-data objects will be used (again in a future patch) as
part of coverage data file writing.
Special handling is required for packages such as "runtime" or
"internal/cpu", where functions in the package execute before the
package "init" func runs. For these packages hard-code the package ID,
then record the position of the package in the overall list so that we
can fix things up later on.
Updates #51430.
Change-Id: I6ca3ddf535197442a2603c6d7a0a9798b8496f40
Reviewed-on: https://go-review.googlesource.com/c/go/+/401234
Reviewed-by: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Than McIntosh <thanm@google.com>
