add cpu-shares to ctr

This allows the cpu shares to be modified via ctr.

Signed-off-by: Michael Crosby <michael@thepasture.io>

cmd/ctr/commands/run/run_unix.go

@@ -70,6 +70,11 @@ var platformRunFlags = []cli.Flag{
 		Usage: "set the CFS cpu quota",
 		Value: 0.0,
 	},
+	cli.IntFlag{
+		Name:  "cpu-shares",
+		Usage: "set the cpu shares",
+		Value: 1024,
+	},
 	cli.BoolFlag{
 		Name:  "cni",
 		Usage: "enable cni networking for the container",
@@ -226,6 +231,10 @@ func NewContainer(ctx gocontext.Context, client *containerd.Client, context *cli
 			opts = append(opts, oci.WithCPUCFS(quota, period))
 		}
 
+		if shares := context.Int("cpu-shares"); shares > 0 {
+			opts = append(opts, oci.WithCPUShares(uint64(shares)))
+		}
+
 		quota := context.Int64("cpu-quota")
 		period := context.Uint64("cpu-period")
 		if quota != -1 || period != 0 {