runtime: rename GODEBUG=profileruntimelocks to runtimecontentionstacks
profileruntimelocks is new in CL 544195, but the name is deceptive. Even
with profileruntimelocks=0, runtime-internal locks are still profiled.
The actual difference is that call stacks are not collected. Instead all
contention is reported at runtime._LostContendedLock.
Rename this setting to runtimecontentionstacks to make its name more
aligned with its behavior.
In addition, for this release the default is profileruntimelocks=0,
meaning that users are fairly likely to encounter
runtime._LostContendedLock. Rename it to
runtime._LostContendedRuntimeLock in an attempt to make it more
intuitive that these are runtime locks, not locks in application code.
For #57071.
Change-Id: I38aac28b2c0852db643d53b1eab3f3bc42a43393
Reviewed-on: https://go-review.googlesource.com/c/go/+/547055 Reviewed-by: Michael Knyszek <mknyszek@google.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Rhys Hiltner <rhys@justin.tv>