Init all vCPU when initializing machine on ARM64

This patch is to solve problem that vCPU timer mess up when
adding vCPU dynamically on ARM64, for detailed information
please refer to:
https://github.com/google/gvisor/issues/5739

There is no influence on x86 and here are main changes for
ARM64:
1. create maxVCPUs number of vCPU in machine initialization
2. we want to sync gvisor vCPU number with host CPU number,
so use smaller number between runtime.NumCPU and
KVM_CAP_MAX_VCPUS to be maxVCPUS
3. put unused vCPUs into architecture-specific map initialvCPUs
4. When machine need to bind a new vCPU with tid, rather
than creating new one, it would pick a vCPU from map initalvCPUs
5. change the setSystemTime function. When vCPU number increasing,
the time cost for function setTSC(use syscall to set cntvoff) is
liner growth from around 300 ns to 100000 ns, and this leads to
the function setSystemTimeLegacy can not get correct offset
value.
6. initializing StdioFDs and goferFD before a platform to avoid
StdioFDs confects with vCPU fds

Signed-off-by: howard zhang <howard.zhang@arm.com>

1 files changed, 31 insertions, 31 deletions

diff --git a/runsc/boot/loader.go b/runsc/boot/loader.go
index 774621970..290a706d2 100644
--- a/runsc/boot/loader.go
+++ b/runsc/boot/loader.go
@@ -226,6 +226,33 @@ func New(args Args) (*Loader, error) {
 		vfs2.Override()
 	}
 
+	// Make host FDs stable between invocations. Host FDs must map to the exact
+	// same number when the sandbox is restored. Otherwise the wrong FD will be
+	// used.
+	info := containerInfo{}
+	newfd := startingStdioFD
+
+	for _, stdioFD := range args.StdioFDs {
+		// Check that newfd is unused to avoid clobbering over it.
+		if _, err := unix.FcntlInt(uintptr(newfd), unix.F_GETFD, 0); !errors.Is(err, unix.EBADF) {
+			if err != nil {
+				return nil, fmt.Errorf("error checking for FD (%d) conflict: %w", newfd, err)
+			}
+			return nil, fmt.Errorf("unable to remap stdios, FD %d is already in use", newfd)
+		}
+
+		err := unix.Dup3(stdioFD, newfd, unix.O_CLOEXEC)
+		if err != nil {
+			return nil, fmt.Errorf("dup3 of stdios failed: %w", err)
+		}
+		info.stdioFDs = append(info.stdioFDs, fd.New(newfd))
+		_ = unix.Close(stdioFD)
+		newfd++
+	}
+	for _, goferFD := range args.GoferFDs {
+		info.goferFDs = append(info.goferFDs, fd.New(goferFD))
+	}
+
 	// Create kernel and platform.
 	p, err := createPlatform(args.Conf, args.Device)
 	if err != nil {
@@ -345,6 +372,7 @@ func New(args Args) (*Loader, error) {
 	if err != nil {
 		return nil, fmt.Errorf("creating init process for root container: %v", err)
 	}
+	info.procArgs = procArgs
 
 	if err := initCompatLogs(args.UserLogFD); err != nil {
 		return nil, fmt.Errorf("initializing compat logs: %v", err)
@@ -355,6 +383,9 @@ func New(args Args) (*Loader, error) {
 		return nil, fmt.Errorf("creating pod mount hints: %v", err)
 	}
 
+	info.conf = args.Conf
+	info.spec = args.Spec
+
 	if kernel.VFS2Enabled {
 		// Set up host mount that will be used for imported fds.
 		hostFilesystem, err := hostvfs2.NewFilesystem(k.VFS())
@@ -369,37 +400,6 @@ func New(args Args) (*Loader, error) {
 		k.SetHostMount(hostMount)
 	}
 
-	info := containerInfo{
-		conf:     args.Conf,
-		spec:     args.Spec,
-		procArgs: procArgs,
-	}
-
-	// Make host FDs stable between invocations. Host FDs must map to the exact
-	// same number when the sandbox is restored. Otherwise the wrong FD will be
-	// used.
-	newfd := startingStdioFD
-	for _, stdioFD := range args.StdioFDs {
-		// Check that newfd is unused to avoid clobbering over it.
-		if _, err := unix.FcntlInt(uintptr(newfd), unix.F_GETFD, 0); !errors.Is(err, unix.EBADF) {
-			if err != nil {
-				return nil, fmt.Errorf("error checking for FD (%d) conflict: %w", newfd, err)
-			}
-			return nil, fmt.Errorf("unable to remap stdios, FD %d is already in use", newfd)
-		}
-
-		err := unix.Dup3(stdioFD, newfd, unix.O_CLOEXEC)
-		if err != nil {
-			return nil, fmt.Errorf("dup3 of stdios failed: %w", err)
-		}
-		info.stdioFDs = append(info.stdioFDs, fd.New(newfd))
-		_ = unix.Close(stdioFD)
-		newfd++
-	}
-	for _, goferFD := range args.GoferFDs {
-		info.goferFDs = append(info.goferFDs, fd.New(goferFD))
-	}
-
 	eid := execID{cid: args.ID}
 	l := &Loader{
 		k:          k,