lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

IPC: make struct ipc_ids static in ipc_namespace

Browse Source 
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
Download Patch File Download Diff File Expand all files Collapse all files

16
ipc/util.h
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