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>
diff --git a/ipc/msg.c b/ipc/msg.c
index 5879bfe..ab0c38b 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -67,9 +67,7 @@
#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 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 @@
}
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);
diff --git a/ipc/namespace.c b/ipc/namespace.c
index cef1139..1fed892 100644
--- a/ipc/namespace.c
+++ b/ipc/namespace.c
@@ -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)
diff --git a/ipc/sem.c b/ipc/sem.c
index 7836edb..1f7e28d 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -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 @@
#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 @@
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);
diff --git a/ipc/shm.c b/ipc/shm.c
index 07f4b7a..fe92471 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -56,9 +56,7 @@
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 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 @@
}
#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 @@
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);
diff --git a/ipc/util.c b/ipc/util.c
index 910db77..fd1b50d 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -833,7 +833,7 @@
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 @@
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 @@
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);
}
diff --git a/ipc/util.h b/ipc/util.h
index ca245fa..f37d160 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -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 @@
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 seq_file;
+struct ipc_ids;
void ipc_init_ids(struct ipc_ids *);
#ifdef CONFIG_PROC_FS