printf, vprintf, snprintf, gc_m_ptr, gc_g_ptr, gc_itab_ptr, gc_unixnanotime.
These were called from C.
There is no more C.
Now that vprintf is gone, delete roundup, which is unsafe (see CL 2814).
Change-Id: If8a7b727d497ffa13165c0d3a1ed62abc18f008c
Reviewed-on: https://go-review.googlesource.com/2824
Reviewed-by: Austin Clements <austin@google.com>
It could happen that mp.printlock++ happens, then on entry to lock,
the goroutine is preempted and then rescheduled onto another m
for the actual call to lock. Now the lock and the printlock++ have
happened on different m's. This can lead to printlock not being
unlocked, which either gives a printing deadlock or a crash when
the goroutine reschedules, because m.locks > 0.
Change-Id: Ib0c08740e1b53de3a93f7ebf9b05f3dceff48b9f
Reviewed-on: https://go-review.googlesource.com/2819
Reviewed-by: Rick Hudson <rlh@golang.org>
I tried to submit this in Go 1.4 as cl/107540044 but tripped over the
changes for getting C off the G stack. This is a rewritten version that
avoids cgo and works directly with the underlying log device.
Change-Id: I14c227dbb4202690c2c67c5a613d6c6689a6662a
Reviewed-on: https://go-review.googlesource.com/1285
Reviewed-by: Keith Randall <khr@golang.org>
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
goprintf is a printf-like print for Go.
It is used in the code generated by 'defer print(...)' and 'go print(...)'.
Normally print(1, 2, 3) turns into
printint(1)
printint(2)
printint(3)
but defer and go need a single function call to give the runtime;
they give the runtime something like goprintf("%d%d%d", 1, 2, 3).
Variadic functions like goprintf cannot be described in the new
type information world, so we have to replace it.
Replace with a custom function, so that defer print(1, 2, 3) turns
into
defer func(a1, a2, a3 int) {
print(a1, a2, a3)
}(1, 2, 3)
(and then the print becomes three different printints as usual).
Fixes#8614.
LGTM=austin
R=austin
CC=golang-codereviews, r
https://golang.org/cl/159700043
This CL contains compiler+runtime changes that detect C code
running on Go (not g0, not gsignal) stacks, and it contains
corrections for what it detected.
The detection works by changing the C prologue to use a different
stack guard word in the G than Go prologue does. On the g0 and
gsignal stacks, that stack guard word is set to the usual
stack guard value. But on ordinary Go stacks, that stack
guard word is set to ^0, which will make any stack split
check fail. The C prologue then calls morestackc instead
of morestack, and morestackc aborts the program with
a message about running C code on a Go stack.
This check catches all C code running on the Go stack
except NOSPLIT code. The NOSPLIT code is allowed,
so the check is complete. Since it is a dynamic check,
the code must execute to be caught. But unlike the static
checks we've been using in cmd/ld, the dynamic check
works with function pointers and other indirect calls.
For example it caught sigpanic being pushed onto Go
stacks in the signal handlers.
Fixes#8667.
LGTM=khr, iant
R=golang-codereviews, khr, iant
CC=golang-codereviews, r
https://golang.org/cl/133700043
