IPC: make struct ipc_ids static in ipc_namespace

Each ipc_namespace contains a table of 3 pointers to struct ipc_ids (3 for
msg, sem and shm, structure used to store all ipcs) These 'struct ipc_ids'
are dynamically allocated for each icp_namespace as the ipc_namespace
itself (for the init namespace, they are initialized with pointers to
static variables instead)

It is so for historical reason: in fact, before the use of idr to store the
ipcs, the ipcs were stored in tables of variable length, depending of the
maximum number of ipc allowed.  Now, these 'struct ipc_ids' have a fixed
size.  As they are allocated in any cases for each new ipc_namespace, there
is no gain of memory in having them allocated separately of the struct
ipc_namespace.

This patch proposes to make this table static in the struct ipc_namespace.
Thus, we can allocate all in once and get rid of all the code needed to
allocate and free these ipc_ids separately.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Acked-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Pierre Peiffer 2008-02-08 04:18:57 -08:00 committed by Linus Torvalds
parent 4b9fcb0ec6
commit ed2ddbf88c
7 changed files with 34 additions and 104 deletions

View file

@ -2,11 +2,20 @@
#define __IPC_NAMESPACE_H__
#include <linux/err.h>
#include <linux/idr.h>
#include <linux/rwsem.h>
struct ipc_ids {
int in_use;
unsigned short seq;
unsigned short seq_max;
struct rw_semaphore rw_mutex;
struct idr ipcs_idr;
};
struct ipc_ids;
struct ipc_namespace {
struct kref kref;
struct ipc_ids *ids[3];
struct ipc_ids ids[3];
int sem_ctls[4];
int used_sems;

View file

@ -67,9 +67,7 @@ struct msg_sender {
#define SEARCH_NOTEQUAL 3
#define SEARCH_LESSEQUAL 4
static struct ipc_ids init_msg_ids;
#define msg_ids(ns) (*((ns)->ids[IPC_MSG_IDS]))
#define msg_ids(ns) ((ns)->ids[IPC_MSG_IDS])
#define msg_unlock(msq) ipc_unlock(&(msq)->q_perm)
#define msg_buildid(id, seq) ipc_buildid(id, seq)
@ -80,30 +78,17 @@ static int newque(struct ipc_namespace *, struct ipc_params *);
static int sysvipc_msg_proc_show(struct seq_file *s, void *it);
#endif
static void __msg_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
void msg_init_ns(struct ipc_namespace *ns)
{
ns->ids[IPC_MSG_IDS] = ids;
ns->msg_ctlmax = MSGMAX;
ns->msg_ctlmnb = MSGMNB;
ns->msg_ctlmni = MSGMNI;
atomic_set(&ns->msg_bytes, 0);
atomic_set(&ns->msg_hdrs, 0);
ipc_init_ids(ids);
ipc_init_ids(&ns->ids[IPC_MSG_IDS]);
}
#ifdef CONFIG_IPC_NS
int msg_init_ns(struct ipc_namespace *ns)
{
struct ipc_ids *ids;
ids = kmalloc(sizeof(struct ipc_ids), GFP_KERNEL);
if (ids == NULL)
return -ENOMEM;
__msg_init_ns(ns, ids);
return 0;
}
void msg_exit_ns(struct ipc_namespace *ns)
{
struct msg_queue *msq;
@ -126,15 +111,12 @@ void msg_exit_ns(struct ipc_namespace *ns)
}
up_write(&msg_ids(ns).rw_mutex);
kfree(ns->ids[IPC_MSG_IDS]);
ns->ids[IPC_MSG_IDS] = NULL;
}
#endif
void __init msg_init(void)
{
__msg_init_ns(&init_ipc_ns, &init_msg_ids);
msg_init_ns(&init_ipc_ns);
ipc_init_proc_interface("sysvipc/msg",
" key msqid perms cbytes qnum lspid lrpid uid gid cuid cgid stime rtime ctime\n",
IPC_MSG_IDS, sysvipc_msg_proc_show);

View file

@ -14,35 +14,18 @@
static struct ipc_namespace *clone_ipc_ns(struct ipc_namespace *old_ns)
{
int err;
struct ipc_namespace *ns;
err = -ENOMEM;
ns = kmalloc(sizeof(struct ipc_namespace), GFP_KERNEL);
if (ns == NULL)
goto err_mem;
return ERR_PTR(-ENOMEM);
err = sem_init_ns(ns);
if (err)
goto err_sem;
err = msg_init_ns(ns);
if (err)
goto err_msg;
err = shm_init_ns(ns);
if (err)
goto err_shm;
sem_init_ns(ns);
msg_init_ns(ns);
shm_init_ns(ns);
kref_init(&ns->kref);
return ns;
err_shm:
msg_exit_ns(ns);
err_msg:
sem_exit_ns(ns);
err_sem:
kfree(ns);
err_mem:
return ERR_PTR(err);
}
struct ipc_namespace *copy_ipcs(unsigned long flags, struct ipc_namespace *ns)

View file

@ -87,14 +87,12 @@
#include <asm/uaccess.h>
#include "util.h"
#define sem_ids(ns) (*((ns)->ids[IPC_SEM_IDS]))
#define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS])
#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm)
#define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid)
#define sem_buildid(id, seq) ipc_buildid(id, seq)
static struct ipc_ids init_sem_ids;
static int newary(struct ipc_namespace *, struct ipc_params *);
static void freeary(struct ipc_namespace *, struct sem_array *);
#ifdef CONFIG_PROC_FS
@ -118,30 +116,17 @@ static int sysvipc_sem_proc_show(struct seq_file *s, void *it);
#define sc_semopm sem_ctls[2]
#define sc_semmni sem_ctls[3]
static void __sem_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
void sem_init_ns(struct ipc_namespace *ns)
{
ns->ids[IPC_SEM_IDS] = ids;
ns->sc_semmsl = SEMMSL;
ns->sc_semmns = SEMMNS;
ns->sc_semopm = SEMOPM;
ns->sc_semmni = SEMMNI;
ns->used_sems = 0;
ipc_init_ids(ids);
ipc_init_ids(&ns->ids[IPC_SEM_IDS]);
}
#ifdef CONFIG_IPC_NS
int sem_init_ns(struct ipc_namespace *ns)
{
struct ipc_ids *ids;
ids = kmalloc(sizeof(struct ipc_ids), GFP_KERNEL);
if (ids == NULL)
return -ENOMEM;
__sem_init_ns(ns, ids);
return 0;
}
void sem_exit_ns(struct ipc_namespace *ns)
{
struct sem_array *sma;
@ -163,15 +148,12 @@ void sem_exit_ns(struct ipc_namespace *ns)
total++;
}
up_write(&sem_ids(ns).rw_mutex);
kfree(ns->ids[IPC_SEM_IDS]);
ns->ids[IPC_SEM_IDS] = NULL;
}
#endif
void __init sem_init (void)
{
__sem_init_ns(&init_ipc_ns, &init_sem_ids);
sem_init_ns(&init_ipc_ns);
ipc_init_proc_interface("sysvipc/sem",
" key semid perms nsems uid gid cuid cgid otime ctime\n",
IPC_SEM_IDS, sysvipc_sem_proc_show);

View file

@ -56,9 +56,7 @@ struct shm_file_data {
static const struct file_operations shm_file_operations;
static struct vm_operations_struct shm_vm_ops;
static struct ipc_ids init_shm_ids;
#define shm_ids(ns) (*((ns)->ids[IPC_SHM_IDS]))
#define shm_ids(ns) ((ns)->ids[IPC_SHM_IDS])
#define shm_unlock(shp) \
ipc_unlock(&(shp)->shm_perm)
@ -72,14 +70,13 @@ static void shm_destroy (struct ipc_namespace *ns, struct shmid_kernel *shp);
static int sysvipc_shm_proc_show(struct seq_file *s, void *it);
#endif
static void __shm_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
void shm_init_ns(struct ipc_namespace *ns)
{
ns->ids[IPC_SHM_IDS] = ids;
ns->shm_ctlmax = SHMMAX;
ns->shm_ctlall = SHMALL;
ns->shm_ctlmni = SHMMNI;
ns->shm_tot = 0;
ipc_init_ids(ids);
ipc_init_ids(&ns->ids[IPC_SHM_IDS]);
}
/*
@ -98,18 +95,6 @@ static void do_shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *shp)
}
#ifdef CONFIG_IPC_NS
int shm_init_ns(struct ipc_namespace *ns)
{
struct ipc_ids *ids;
ids = kmalloc(sizeof(struct ipc_ids), GFP_KERNEL);
if (ids == NULL)
return -ENOMEM;
__shm_init_ns(ns, ids);
return 0;
}
void shm_exit_ns(struct ipc_namespace *ns)
{
struct shmid_kernel *shp;
@ -131,15 +116,12 @@ void shm_exit_ns(struct ipc_namespace *ns)
total++;
}
up_write(&shm_ids(ns).rw_mutex);
kfree(ns->ids[IPC_SHM_IDS]);
ns->ids[IPC_SHM_IDS] = NULL;
}
#endif
void __init shm_init (void)
{
__shm_init_ns(&init_ipc_ns, &init_shm_ids);
shm_init_ns(&init_ipc_ns);
ipc_init_proc_interface("sysvipc/shm",
" key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime\n",
IPC_SHM_IDS, sysvipc_shm_proc_show);

View file

@ -833,7 +833,7 @@ static void *sysvipc_proc_next(struct seq_file *s, void *it, loff_t *pos)
if (ipc && ipc != SEQ_START_TOKEN)
ipc_unlock(ipc);
return sysvipc_find_ipc(iter->ns->ids[iface->ids], *pos, pos);
return sysvipc_find_ipc(&iter->ns->ids[iface->ids], *pos, pos);
}
/*
@ -846,7 +846,7 @@ static void *sysvipc_proc_start(struct seq_file *s, loff_t *pos)
struct ipc_proc_iface *iface = iter->iface;
struct ipc_ids *ids;
ids = iter->ns->ids[iface->ids];
ids = &iter->ns->ids[iface->ids];
/*
* Take the lock - this will be released by the corresponding
@ -877,7 +877,7 @@ static void sysvipc_proc_stop(struct seq_file *s, void *it)
if (ipc && ipc != SEQ_START_TOKEN)
ipc_unlock(ipc);
ids = iter->ns->ids[iface->ids];
ids = &iter->ns->ids[iface->ids];
/* Release the lock we took in start() */
up_read(&ids->rw_mutex);
}

View file

@ -10,7 +10,6 @@
#ifndef _IPC_UTIL_H
#define _IPC_UTIL_H
#include <linux/idr.h>
#include <linux/err.h>
#define USHRT_MAX 0xffff
@ -22,22 +21,14 @@ void shm_init (void);
struct ipc_namespace;
int sem_init_ns(struct ipc_namespace *ns);
int msg_init_ns(struct ipc_namespace *ns);
int shm_init_ns(struct ipc_namespace *ns);
void sem_init_ns(struct ipc_namespace *ns);
void msg_init_ns(struct ipc_namespace *ns);
void shm_init_ns(struct ipc_namespace *ns);
void sem_exit_ns(struct ipc_namespace *ns);
void msg_exit_ns(struct ipc_namespace *ns);
void shm_exit_ns(struct ipc_namespace *ns);
struct ipc_ids {
int in_use;
unsigned short seq;
unsigned short seq_max;
struct rw_semaphore rw_mutex;
struct idr ipcs_idr;
};
/*
* Structure that holds the parameters needed by the ipc operations
* (see after)
@ -68,6 +59,7 @@ struct ipc_ops {
};
struct seq_file;
struct ipc_ids;
void ipc_init_ids(struct ipc_ids *);
#ifdef CONFIG_PROC_FS