cannon: Undo changes to memprofile patching (#11420)

cannon/mipsevm/program/patch.go

@@ -47,12 +47,16 @@ func PatchGo(f *elf.File, st mipsevm.FPVMState) error {
 			})); err != nil {
 				return fmt.Errorf("failed to patch Go runtime.gcenable: %w", err)
 			}
+		case "runtime.MemProfileRate":
+			if err := st.GetMemory().SetMemoryRange(uint32(s.Value), bytes.NewReader(make([]byte, 4))); err != nil { // disable mem profiling, to avoid a lot of unnecessary floating point ops
+				return err
+			}
 		}
 	}
 	return nil
 }
 
-// TODO(cp-903) Consider setting envar "GODEBUG=memprofilerate=0" for go programs to disable memprofiling
+// TODO(cp-903) Consider setting envar "GODEBUG=memprofilerate=0" for go programs to disable memprofiling, instead of patching it out in PatchGo()
 func PatchStack(st mipsevm.FPVMState) error {
 	// setup stack pointer
 	sp := uint32(0x7f_ff_d0_00)

op-program/client/cmd/main.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"os"
-	"runtime"
 
 	"github.com/ethereum/go-ethereum/log"
 
@@ -10,13 +9,6 @@ import (
 	oplog "github.com/ethereum-optimism/optimism/op-service/log"
 )
 
-var _ = func() bool {
-	// Disable mem profiling, to avoid a lot of unnecessary floating point ops
-	// TODO(cp-903) Consider cutting this in favor patching envar "GODEBUG=memprofilerate=0" into cannon go programs
-	runtime.MemProfileRate = 0
-	return true
-}()
-
 func main() {
 	// Default to a machine parsable but relatively human friendly log format.
 	// Don't do anything fancy to detect if color output is supported.