Commit ed2ddbf8 authored by Pierre Peiffer's avatar Pierre Peiffer Committed by Linus Torvalds
Browse files

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: default avatarPierre Peiffer <pierre.peiffer@bull.net>
Acked-by: default avatarCedric Le Goater <clg@fr.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 4b9fcb0e

include/linux/ipc_namespace.h

+11 −2
Original line number Diff line number Diff line
@@ -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;

ipc/msg.c

+4 −22
Original line number Diff line number Diff line
@@ -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);

ipc/namespace.c

+4 −21
Original line number Diff line number Diff line
@@ -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)

ipc/sem.c

+4 −22
Original line number Diff line number Diff line
@@ -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);

ipc/shm.c

+4 −22
Original line number Diff line number Diff line
@@ -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);

CRA Git | Maintained and supported by SUSTech CRA and CCSE