diff options
Diffstat (limited to 'src/runtime/stack.go')
| -rw-r--r-- | src/runtime/stack.go | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/src/runtime/stack.go b/src/runtime/stack.go index cdccdcc2c5..babfdfccf0 100644 --- a/src/runtime/stack.go +++ b/src/runtime/stack.go @@ -92,6 +92,10 @@ const ( // The stack guard is a pointer this many bytes above the // bottom of the stack. + // + // The guard leaves enough room for one _StackSmall frame plus + // a _StackLimit chain of NOSPLIT calls plus _StackSystem + // bytes for the OS. _StackGuard = 928*sys.StackGuardMultiplier + _StackSystem // After a stack split check the SP is allowed to be this @@ -123,15 +127,16 @@ const ( const ( uintptrMask = 1<<(8*sys.PtrSize) - 1 + // The values below can be stored to g.stackguard0 to force + // the next stack check to fail. + // These are all larger than any real SP. + // Goroutine preemption request. - // Stored into g->stackguard0 to cause split stack check failure. - // Must be greater than any real sp. // 0xfffffade in hex. stackPreempt = uintptrMask & -1314 - // Thread is forking. - // Stored into g->stackguard0 to cause split stack check failure. - // Must be greater than any real sp. + // Thread is forking. Causes a split stack check failure. + // 0xfffffb2e in hex. stackFork = uintptrMask & -1234 // Force a stack movement. Used for debugging. |