While we are here, give the gc helper a real function name
that will appear in stack traces.
LGTM=rlh
R=rlh
CC=dvyukov, golang-codereviews
https://golang.org/cl/133470043
Also fix a bunch of bugs:
1. Accesses to last_gc must be atomic (it's int64).
2. last_gc still can be 0 during first checks in sysmon, check for 0.
3. forcegc.g can be unitialized when sysmon accesses it:
forcegc.g is initialized by main goroutine (forcegc.g = newproc1(...)),
and main goroutine is unsynchronized with both sysmon and forcegc goroutine.
Initialize forcegc.g in the forcegc goroutine itself instead.
LGTM=khr
R=golang-codereviews, khr
CC=golang-codereviews, rsc
https://golang.org/cl/136770043
Mutex is consistent with package sync, and when in the
unexported Go form it avoids having a conflcit between
the type (now mutex) and the function (lock).
LGTM=iant
R=golang-codereviews, iant
CC=dvyukov, golang-codereviews, r
https://golang.org/cl/133140043
uintptr or uint64 in the runtime C were turning into uint in the Go,
bool was turning into uint8, and so on. Fix that.
Also delete Go wrappers for C functions.
The C functions can be called directly now
(but still eventually need to be converted to Go).
LGTM=bradfitz, minux, iant
R=golang-codereviews, bradfitz, iant, minux
CC=golang-codereviews, khr, r
https://golang.org/cl/138740043
Every change to g->atomicstatus is now done atomically so that we can
ensure that all gs pass through a gc safepoint on demand. This allows
the GC to move from one phase to the next safely. In some phases the
stack will be scanned. This CL only deals with the infrastructure that
allows g->atomicstatus to go from one state to another. Future CLs
will deal with scanning and monitoring what phase the GC is in.
The major change was to moving to using a Gscan bit to indicate that
the status is in a scan state. The only bug fix was in oldstack where
I wasn't moving to a Gcopystack state in order to block scanning until
the new stack was in place. The proc.go file is waiting for an atomic
load instruction.
LGTM=rsc
R=golang-codereviews, dvyukov, josharian, rsc
CC=golang-codereviews, khr
https://golang.org/cl/132960044
These are required for chans, semaphores, timers, etc.
LGTM=khr
R=golang-codereviews, khr
CC=golang-codereviews, rlh, rsc
https://golang.org/cl/123640043
