[Devel] Re: [PATCH] Consolidate IPC namespace cleanup functions

[Cedric Le Goater]

Pavel Emelyanov wrote:
> When the IPC namespace is terminated all the IPC objects (i.e. ids)
> living in it are freed. This is done in a similar way in X_exit_ns()
> functions. All the code can be consolidated, saving 122 bytes when
> the NAMESPACES are on.
> 
> This patch must be applied after the ones with the NAMESPACES config
> option introduced.
> 
> Signed-off-by: Pavel Emelyanov <xemul at openvz.org>


Acked-by: Cedric Le Goater <clg at fr.ibm.com>

Thanks Pavel !

C.


> 
> ---
> 
>  ipc/msg.c       |   23 ++++-------------------
>  ipc/namespace.c |   39 +++++++++++++++++++++++++++++++++++++++
>  ipc/sem.c       |   23 ++++-------------------
>  ipc/shm.c       |   23 ++++-------------------
>  ipc/util.h      |    6 +++---
>  5 files changed, 54 insertions(+), 60 deletions(-)
> 
> diff --git a/ipc/namespace.c b/ipc/namespace.c
> index cef1139..98de4e5 100644
> --- a/ipc/namespace.c
> +++ b/ipc/namespace.c
> @@ -12,6 +12,45 @@
> 
>  #include "util.h"
> 
> +static void ipc_exit_ns(struct ipc_namespace *ns, struct ipc_ids *ids,
> +		void (*free_fn)(struct ipc_namespace *ns, void *id))
> +{
> +	void *id;
> +	int next_id;
> +	int total, in_use;
> +
> +	mutex_lock(&ids->mutex);
> +
> +	in_use = ids->in_use;
> +
> +	for (total = 0, next_id = 0; total < in_use; next_id++) {
> +		id = idr_find(&ids->ipcs_idr, next_id);
> +		if (id == NULL)
> +			continue;
> +
> +		free_fn(ns, id);
> +		total++;
> +	}
> +	mutex_unlock(&ids->mutex);
> +
> +	kfree(ids);
> +}
> +
> +static inline void sem_exit_ns(struct ipc_namespace *ns)
> +{
> +	ipc_exit_ns(ns, ns->ids[IPC_SEM_IDS], sem_free);
> +}
> +
> +static inline void msg_exit_ns(struct ipc_namespace *ns)
> +{
> +	ipc_exit_ns(ns, ns->ids[IPC_MSG_IDS], msg_free);
> +}
> +
> +static inline void shm_exit_ns(struct ipc_namespace *ns)
> +{
> +	ipc_exit_ns(ns, ns->ids[IPC_SHM_IDS], shm_free);
> +}
> +
>  static struct ipc_namespace *clone_ipc_ns(struct ipc_namespace *old_ns)
>  {
>  	int err;
> diff --git a/ipc/sem.c b/ipc/sem.c
> index 2e9f449..8027a30 100644
> --- a/ipc/sem.c
> +++ b/ipc/sem.c
> @@ -144,28 +144,13 @@ int sem_init_ns(struct ipc_namespace *ns
>  	return 0;
>  }
> 
> -void sem_exit_ns(struct ipc_namespace *ns)
> +void sem_free(struct ipc_namespace *ns, void *id)
>  {
>  	struct sem_array *sma;
> -	int next_id;
> -	int total, in_use;
> 
> -	mutex_lock(&sem_ids(ns).mutex);
> -
> -	in_use = sem_ids(ns).in_use;
> -
> -	for (total = 0, next_id = 0; total < in_use; next_id++) {
> -		sma = idr_find(&sem_ids(ns).ipcs_idr, next_id);
> -		if (sma == NULL)
> -			continue;
> -		ipc_lock_by_ptr(&sma->sem_perm);
> -		freeary(ns, sma);
> -		total++;
> -	}
> -	mutex_unlock(&sem_ids(ns).mutex);
> -
> -	kfree(ns->ids[IPC_SEM_IDS]);
> -	ns->ids[IPC_SEM_IDS] = NULL;
> +	sma = (struct sem_array *)id;
> +	ipc_lock_by_ptr(&sma->sem_perm);
> +	freeary(ns, sma);
>  }
>  #endif
> 
> diff --git a/ipc/msg.c b/ipc/msg.c
> index eb74965..9b8a155 100644
> --- a/ipc/msg.c
> +++ b/ipc/msg.c
> @@ -106,28 +106,13 @@ int msg_init_ns(struct ipc_namespace *ns
>  	return 0;
>  }
> 
> -void msg_exit_ns(struct ipc_namespace *ns)
> +void msg_free(struct ipc_namespace *ns, void *id)
>  {
>  	struct msg_queue *msq;
> -	int next_id;
> -	int total, in_use;
> 
> -	mutex_lock(&msg_ids(ns).mutex);
> -
> -	in_use = msg_ids(ns).in_use;
> -
> -	for (total = 0, next_id = 0; total < in_use; next_id++) {
> -		msq = idr_find(&msg_ids(ns).ipcs_idr, next_id);
> -		if (msq == NULL)
> -			continue;
> -		ipc_lock_by_ptr(&msq->q_perm);
> -		freeque(ns, msq);
> -		total++;
> -	}
> -	mutex_unlock(&msg_ids(ns).mutex);
> -
> -	kfree(ns->ids[IPC_MSG_IDS]);
> -	ns->ids[IPC_MSG_IDS] = NULL;
> +	msq = (struct msg_queue *)id;
> +	ipc_lock_by_ptr(&msq->q_perm);
> +	freeque(ns, msq);
>  }
>  #endif
> 
> diff --git a/ipc/shm.c b/ipc/shm.c
> index 2717cbc..8f50166 100644
> --- a/ipc/shm.c
> +++ b/ipc/shm.c
> @@ -111,28 +111,13 @@ int shm_init_ns(struct ipc_namespace *ns
>  	return 0;
>  }
> 
> -void shm_exit_ns(struct ipc_namespace *ns)
> +void shm_free(struct ipc_namespace *ns, void *id)
>  {
>  	struct shmid_kernel *shp;
> -	int next_id;
> -	int total, in_use;
> -
> -	mutex_lock(&shm_ids(ns).mutex);
> -
> -	in_use = shm_ids(ns).in_use;
> -
> -	for (total = 0, next_id = 0; total < in_use; next_id++) {
> -		shp = idr_find(&shm_ids(ns).ipcs_idr, next_id);
> -		if (shp == NULL)
> -			continue;
> -		ipc_lock_by_ptr(&shp->shm_perm);
> -		do_shm_rmid(ns, shp);
> -		total++;
> -	}
> -	mutex_unlock(&shm_ids(ns).mutex);
> 
> -	kfree(ns->ids[IPC_SHM_IDS]);
> -	ns->ids[IPC_SHM_IDS] = NULL;
> +	shp = (struct shmid_kernel *)id;
> +	ipc_lock_by_ptr(&shp->shm_perm);
> +	do_shm_rmid(ns, shp);
>  }
>  #endif
> 
> diff --git a/ipc/util.h b/ipc/util.h
> index 8972402..f1f0a31 100644
> --- a/ipc/util.h
> +++ b/ipc/util.h
> @@ -26,9 +26,9 @@ 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_exit_ns(struct ipc_namespace *ns);
> -void msg_exit_ns(struct ipc_namespace *ns);
> -void shm_exit_ns(struct ipc_namespace *ns);
> +void sem_free(struct ipc_namespace *ns, void *id);
> +void msg_free(struct ipc_namespace *ns, void *id);
> +void shm_free(struct ipc_namespace *ns, void *id);
> 
>  struct ipc_ids {
>  	int in_use;