runtime: do not set m->locks around memory allocation If slice append is the only place where a program allocates, then it will consume all available memory w/o triggering GC. This was demonstrated in the issue. Fixes issue 7922.
runtime: do not set m->locks around memory allocation
If slice append is the only place where a program allocates,
then it will consume all available memory w/o triggering GC.
This was demonstrated in the issue.
Fixes issue 7922.

LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews, iant, khr
https://codereview.appspot.com/91010048

h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang