From 8fc3b9cba2b35e02421acbc5ec13454a5a712564 Mon Sep 17 00:00:00 2001
From: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Date: Mon, 26 Oct 2015 15:39:02 -0400
Subject: [PATCH] Add support for kmem.tcp limit

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
---
 README.md                                     |  1 +
 libcontainer/cgroups/fs/memory.go             |  5 ++++
 libcontainer/cgroups/fs/memory_test.go        | 28 +++++++++++++++++++
 libcontainer/cgroups/systemd/apply_systemd.go |  6 ++++
 libcontainer/configs/cgroup_unix.go           |  3 ++
 spec.go                                       |  1 +
 6 files changed, 44 insertions(+)

diff --git a/README.md b/README.md
index 44c7e871f15..ff20c43777b 100644
--- a/README.md
+++ b/README.md
@@ -243,6 +243,7 @@ user with uid and gid of `0` defined within that file-system.
 				"reservation": 0,
 				"swap": 0,
 				"kernel": 0,
+				"kernelTCP": 0,
 				"swappiness": -1
 			},
 			"cpu": {
diff --git a/libcontainer/cgroups/fs/memory.go b/libcontainer/cgroups/fs/memory.go
index 19dfcc72639..6738c3a3c8a 100644
--- a/libcontainer/cgroups/fs/memory.go
+++ b/libcontainer/cgroups/fs/memory.go
@@ -73,6 +73,11 @@ func (s *MemoryGroup) Set(path string, cgroup *configs.Cgroup) error {
 			return err
 		}
 	}
+	if cgroup.KernelMemoryTCP > 0 {
+		if err := writeFile(path, "memory.kmem.tcp.limit_in_bytes", strconv.FormatInt(cgroup.KernelMemoryTCP, 10)); err != nil {
+			return err
+		}
+	}
 
 	if cgroup.OomKillDisable {
 		if err := writeFile(path, "memory.oom_control", "1"); err != nil {
diff --git a/libcontainer/cgroups/fs/memory_test.go b/libcontainer/cgroups/fs/memory_test.go
index d7b5e5f435e..6f20f603f2c 100644
--- a/libcontainer/cgroups/fs/memory_test.go
+++ b/libcontainer/cgroups/fs/memory_test.go
@@ -113,6 +113,34 @@ func TestMemorySetKernelMemory(t *testing.T) {
 	}
 }
 
+func TestMemorySetKernelMemory(t *testing.T) {
+	helper := NewCgroupTestUtil("memory", t)
+	defer helper.cleanup()
+
+	const (
+		kernelMemoryTCPBefore = 314572800 // 300M
+		kernelMemoryTCPAfter  = 524288000 // 500M
+	)
+
+	helper.writeFileContents(map[string]string{
+		"memory.kmem.tcp.limit_in_bytes": strconv.Itoa(kernelMemoryTCPBefore),
+	})
+
+	helper.CgroupData.c.KernelMemoryTCP = kernelMemoryTCPAfter
+	memory := &MemoryGroup{}
+	if err := memory.Set(helper.CgroupPath, helper.CgroupData.c); err != nil {
+		t.Fatal(err)
+	}
+
+	value, err := getCgroupParamUint(helper.CgroupPath, "memory.kmem.tcp.limit_in_bytes")
+	if err != nil {
+		t.Fatalf("Failed to parse memory.kmem.tcp.limit_in_bytes - %s", err)
+	}
+	if value != kernelMemoryTCPAfter {
+		t.Fatal("Got the wrong value, set memory.kmem.tcp.limit_in_bytes failed.")
+	}
+}
+
 func TestMemorySetMemorySwappinessDefault(t *testing.T) {
 	helper := NewCgroupTestUtil("memory", t)
 	defer helper.cleanup()
diff --git a/libcontainer/cgroups/systemd/apply_systemd.go b/libcontainer/cgroups/systemd/apply_systemd.go
index 7a422b3c794..534e892f317 100644
--- a/libcontainer/cgroups/systemd/apply_systemd.go
+++ b/libcontainer/cgroups/systemd/apply_systemd.go
@@ -539,6 +539,12 @@ func joinMemory(c *configs.Cgroup, pid int) error {
 			return err
 		}
 	}
+	if c.KernelMemoryTCP > 0 {
+		err = writeFile(path, "memory.kmem.tcp.limit_in_bytes", strconv.FormatInt(c.KernelMemoryTCP, 10))
+		if err != nil {
+			return err
+		}
+	}
 	if c.OomKillDisable {
 		if err := writeFile(path, "memory.oom_control", "1"); err != nil {
 			return err
diff --git a/libcontainer/configs/cgroup_unix.go b/libcontainer/configs/cgroup_unix.go
index 24f93c1ad6e..3ad878d5807 100644
--- a/libcontainer/configs/cgroup_unix.go
+++ b/libcontainer/configs/cgroup_unix.go
@@ -35,6 +35,9 @@ type Cgroup struct {
 	// Kernel memory limit (in bytes)
 	KernelMemory int64 `json:"kernel_memory"`
 
+	// Kernel memory limit for TCP using (in bytes)
+	KernelMemoryTCP int64 `json:"kernel_memory_tcp"`
+
 	// CPU shares (relative weight vs. other containers)
 	CpuShares int64 `json:"cpu_shares"`
 
diff --git a/spec.go b/spec.go
index 69cf47b799a..e13ba4735ac 100644
--- a/spec.go
+++ b/spec.go
@@ -448,6 +448,7 @@ func createCgroupConfig(name string, spec *specs.LinuxRuntimeSpec, devices []*co
 	c.MemoryReservation = r.Memory.Reservation
 	c.MemorySwap = r.Memory.Swap
 	c.KernelMemory = r.Memory.Kernel
+	c.KernelMemoryTCP = r.Memory.KernelTCP
 	c.MemorySwappiness = r.Memory.Swappiness
 	c.CpuShares = r.CPU.Shares
 	c.CpuQuota = r.CPU.Quota