runtime: restore correct m in gtraceback
If gtraceback is used to get a stack trace of a g running in the same m,
as can happen if we collect a stack trace from a g0, then restore the
old m value, don't clear it.
Change-Id: I950a3c182d0b79dd84204c59530c57edb1e100e1
Reviewed-on: https://go-review.googlesource.com/41138
Reviewed-by: Than McIntosh <thanm@google.com>
diff --git a/libgo/runtime/proc.c b/libgo/runtime/proc.c
index 23cfb73..5febe0c 100644
--- a/libgo/runtime/proc.c
+++ b/libgo/runtime/proc.c
@@ -441,21 +441,23 @@
}
// Do a stack trace of gp, and then restore the context to
-// gp->dotraceback.
+// gp->traceback->gp.
void
gtraceback(G* gp)
{
Traceback* traceback;
+ M* holdm;
traceback = gp->traceback;
gp->traceback = nil;
- if(gp->m != nil && gp->m != g->m)
+ holdm = gp->m;
+ if(holdm != nil && holdm != g->m)
runtime_throw("gtraceback: m is not nil");
gp->m = traceback->gp->m;
traceback->c = runtime_callers(1, traceback->locbuf,
sizeof traceback->locbuf / sizeof traceback->locbuf[0], false);
- gp->m = nil;
+ gp->m = holdm;
runtime_gogo(traceback->gp);
}
