add a kmem_cache for nsproxy objects

It should improve performance in some scenarii where a lot of
these nsproxy objects are created by unsharing namespaces. This is
a typical use of virtual servers that are being created or entered.

This is also a good tool to find leaks and gather statistics on
namespace usage.

Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Cedric Le Goater 2007-07-15 23:41:07 -07:00 committed by Linus Torvalds
parent 467e9f4b50
commit 98c0d07cbf

View file

@ -21,6 +21,8 @@
#include <linux/utsname.h>
#include <linux/pid_namespace.h>
static struct kmem_cache *nsproxy_cachep;
struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy);
static inline void get_nsproxy(struct nsproxy *ns)
@ -43,9 +45,11 @@ static inline struct nsproxy *clone_nsproxy(struct nsproxy *orig)
{
struct nsproxy *ns;
ns = kmemdup(orig, sizeof(struct nsproxy), GFP_KERNEL);
if (ns)
ns = kmem_cache_alloc(nsproxy_cachep, GFP_KERNEL);
if (ns) {
memcpy(ns, orig, sizeof(struct nsproxy));
atomic_set(&ns->count, 1);
}
return ns;
}
@ -109,7 +113,7 @@ static struct nsproxy *create_new_namespaces(int flags, struct task_struct *tsk,
if (new_nsp->mnt_ns)
put_mnt_ns(new_nsp->mnt_ns);
out_ns:
kfree(new_nsp);
kmem_cache_free(nsproxy_cachep, new_nsp);
return ERR_PTR(err);
}
@ -160,7 +164,7 @@ void free_nsproxy(struct nsproxy *ns)
put_pid_ns(ns->pid_ns);
if (ns->user_ns)
put_user_ns(ns->user_ns);
kfree(ns);
kmem_cache_free(nsproxy_cachep, ns);
}
/*
@ -185,3 +189,12 @@ int unshare_nsproxy_namespaces(unsigned long unshare_flags,
err = PTR_ERR(*new_nsp);
return err;
}
static int __init nsproxy_cache_init(void)
{
nsproxy_cachep = kmem_cache_create("nsproxy", sizeof(struct nsproxy),
0, SLAB_PANIC, NULL, NULL);
return 0;
}
module_init(nsproxy_cache_init);