Stowage/go
2
0
Fork 0
mirror of https://github.com/golang/go.git synced 2025-12-08 06:10:04 +00:00
Code Issues Projects Releases Packages Wiki Activity

Revert "runtime, cmd: rationalize StackLimit and StackGuard"

Browse source 
This reverts commit CL 486380.

Submitted out of order and breaks bootstrap.

Change-Id: I67bd225094b5c9713b97f70feba04d2c99b7da76
Reviewed-on: https://go-review.googlesource.com/c/go/+/486916
Reviewed-by: David Chase <drchase@google.com>
TryBot-Bypass: Austin Clements <austin@google.com>
This commit is contained in:
Austin Clements 2023-04-20 16:09:48 +00:00
parent df777cfa15
commit d11ff3f081
6 changed files with 34 additions and 25 deletions
Download patch file Download diff file Expand all files Collapse all files

19
src/runtime/stack.go
View file

@ -85,18 +85,19 @@ const (
_FixedStack6 = _FixedStack5 | (_FixedStack5 >> 16)
_FixedStack = _FixedStack6 + 1
// stackNosplit is the maximum number of bytes that a chain of NOSPLIT
// functions can use.
// This arithmetic must match that in cmd/internal/objabi/stack.go:StackNosplit.
stackNosplit = abi.StackNosplitBase * sys.StackGuardMultiplier
// The stack guard is a pointer this many bytes above the
// bottom of the stack.
//
// The guard leaves enough room for a stackNosplit chain of NOSPLIT calls
// plus one stackSmall frame plus stackSystem bytes for the OS.
// The guard leaves enough room for one _StackSmall frame plus
// a _StackLimit chain of NOSPLIT calls plus _StackSystem
// bytes for the OS.
// This arithmetic must match that in cmd/internal/objabi/stack.go:StackLimit.
_StackGuard = stackNosplit + _StackSystem + abi.StackSmall
_StackGuard = 928*sys.StackGuardMultiplier + _StackSystem
// The maximum number of bytes that a chain of NOSPLIT
// functions can use.
// This arithmetic must match that in cmd/internal/objabi/stack.go:StackLimit.
_StackLimit = _StackGuard - _StackSystem - abi.StackSmall
)
const (
@ -1210,7 +1211,7 @@ func shrinkstack(gp *g) {
// down to the SP plus the stack guard space that ensures
// there's room for nosplit functions.
avail := gp.stack.hi - gp.stack.lo
if used := gp.stack.hi - gp.sched.sp + stackNosplit; used >= avail/4 {
if used := gp.stack.hi - gp.sched.sp + _StackLimit; used >= avail/4 {
return
}