From 4d89dc6ab2711258bfd12c72d753f3ad56b244e2 Mon Sep 17 00:00:00 2001 From: Nadia Derbey Date: Tue, 29 Apr 2008 01:00:40 -0700 Subject: [PATCH] ipc: scale msgmni to the number of ipc namespaces Since all the namespaces see the same amount of memory (the total one) this patch introduces a new variable that counts the ipc namespaces and divides msg_ctlmni by this counter. Signed-off-by: Nadia Derbey Cc: Yasunori Goto Cc: Matt Helsley Cc: Mingming Cao Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/ipc_namespace.h | 1 + ipc/msg.c | 10 +++++++--- ipc/namespace.c | 3 +++ ipc/util.c | 3 +++ 4 files changed, 14 insertions(+), 3 deletions(-) diff --git a/include/linux/ipc_namespace.h b/include/linux/ipc_namespace.h index e4451d1da7..878d7ac286 100644 --- a/include/linux/ipc_namespace.h +++ b/include/linux/ipc_namespace.h @@ -33,6 +33,7 @@ struct ipc_namespace { }; extern struct ipc_namespace init_ipc_ns; +extern atomic_t nr_ipc_ns; #ifdef CONFIG_SYSVIPC #define INIT_IPC_NS(ns) .ns = &init_ipc_ns, diff --git a/ipc/msg.c b/ipc/msg.c index 9e7211122e..be8449d48a 100644 --- a/ipc/msg.c +++ b/ipc/msg.c @@ -81,24 +81,28 @@ static int sysvipc_msg_proc_show(struct seq_file *s, void *it); /* * Scale msgmni with the available lowmem size: the memory dedicated to msg * queues should occupy at most 1/MSG_MEM_SCALE of lowmem. - * This should be done staying within the (MSGMNI , IPCMNI) range. + * Also take into account the number of nsproxies created so far. + * This should be done staying within the (MSGMNI , IPCMNI/nr_ipc_ns) range. */ static void recompute_msgmni(struct ipc_namespace *ns) { struct sysinfo i; unsigned long allowed; + int nb_ns; si_meminfo(&i); allowed = (((i.totalram - i.totalhigh) / MSG_MEM_SCALE) * i.mem_unit) / MSGMNB; + nb_ns = atomic_read(&nr_ipc_ns); + allowed /= nb_ns; if (allowed < MSGMNI) { ns->msg_ctlmni = MSGMNI; goto out_callback; } - if (allowed > IPCMNI) { - ns->msg_ctlmni = IPCMNI; + if (allowed > IPCMNI / nb_ns) { + ns->msg_ctlmni = IPCMNI / nb_ns; goto out_callback; } diff --git a/ipc/namespace.c b/ipc/namespace.c index 1b967655eb..fe3c97aa99 100644 --- a/ipc/namespace.c +++ b/ipc/namespace.c @@ -20,6 +20,8 @@ static struct ipc_namespace *clone_ipc_ns(struct ipc_namespace *old_ns) if (ns == NULL) return ERR_PTR(-ENOMEM); + atomic_inc(&nr_ipc_ns); + sem_init_ns(ns); msg_init_ns(ns); shm_init_ns(ns); @@ -83,4 +85,5 @@ void free_ipc_ns(struct kref *kref) msg_exit_ns(ns); shm_exit_ns(ns); kfree(ns); + atomic_dec(&nr_ipc_ns); } diff --git a/ipc/util.c b/ipc/util.c index cb017c7b93..c27f0e92f4 100644 --- a/ipc/util.c +++ b/ipc/util.c @@ -52,6 +52,9 @@ struct ipc_namespace init_ipc_ns = { }, }; +atomic_t nr_ipc_ns = ATOMIC_INIT(1); + + /** * ipc_init - initialise IPC subsystem * -- 2.39.5