lkml.org 
[lkml]   [2007]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 2.6.24-rc3-mm1 1/3] IPC: make struct ipc_ids static in ipc_namespace
From: Pierre Peiffer <pierre.peiffer@bull.net>

Each ipc_namespace contains a table of 3 pointers to struct ipc_ids (3 for
msg, sem and shm, structure used to store each ipcs)
These pointers are dynamically allocated for each icp_namespace as the
ipc_namespace itself (for the init namespace, they are initialized with
pointer 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 ipcs 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>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
---
include/linux/ipc_namespace.h | 13 +++++++++++--
ipc/msg.c | 26 ++++----------------------
ipc/namespace.c | 25 ++++---------------------
ipc/sem.c | 26 ++++----------------------
ipc/shm.c | 26 ++++----------------------
ipc/util.c | 6 +++---
ipc/util.h | 16 ++++------------
7 files changed, 34 insertions(+), 104 deletions(-)

Index: b/include/linux/ipc_namespace.h
===================================================================
--- a/include/linux/ipc_namespace.h
+++ b/include/linux/ipc_namespace.h
@@ -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;
Index: b/ipc/msg.c
===================================================================
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -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 *
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(&msg_ids(ns));
}

#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 *n
}

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);
Index: b/ipc/namespace.c
===================================================================
--- 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)
Index: b/ipc/sem.c
===================================================================
--- 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 @@ static int sysvipc_sem_proc_show(struct
#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(&sem_ids(ns));
}

#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 *n
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);
Index: b/ipc/util.c
===================================================================
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -782,7 +782,7 @@ static void *sysvipc_proc_next(struct se
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);
}

/*
@@ -795,7 +795,7 @@ static void *sysvipc_proc_start(struct s
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
@@ -826,7 +826,7 @@ static void sysvipc_proc_stop(struct seq
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);
}
Index: b/ipc/util.h
===================================================================
--- 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 @@ 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
Index: b/ipc/shm.c
===================================================================
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -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_name
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(&shm_ids(ns));
}

/*
@@ -98,18 +95,6 @@ static void do_shm_rmid(struct ipc_names
}

#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 *n
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);
--
Pierre Peiffer
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-11-27 15:53    [W:0.048 / U:0.240 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site