diff options
Diffstat (limited to 'ipc/msg.c')
| -rw-r--r-- | ipc/msg.c | 37 |
1 files changed, 36 insertions, 1 deletions
diff --git a/ipc/msg.c b/ipc/msg.c index 805ee08ec8bb..9e7211122e27 100644 --- a/ipc/msg.c +++ b/ipc/msg.c @@ -27,6 +27,7 @@ #include <linux/msg.h> #include <linux/spinlock.h> #include <linux/init.h> +#include <linux/mm.h> #include <linux/proc_fs.h> #include <linux/list.h> #include <linux/security.h> @@ -77,11 +78,45 @@ static int newque(struct ipc_namespace *, struct ipc_params *); static int sysvipc_msg_proc_show(struct seq_file *s, void *it); #endif +/* + * 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. + */ +static void recompute_msgmni(struct ipc_namespace *ns) +{ + struct sysinfo i; + unsigned long allowed; + + si_meminfo(&i); + allowed = (((i.totalram - i.totalhigh) / MSG_MEM_SCALE) * i.mem_unit) + / MSGMNB; + + if (allowed < MSGMNI) { + ns->msg_ctlmni = MSGMNI; + goto out_callback; + } + + if (allowed > IPCMNI) { + ns->msg_ctlmni = IPCMNI; + goto out_callback; + } + + ns->msg_ctlmni = allowed; + +out_callback: + + printk(KERN_INFO "msgmni has been set to %d for ipc namespace %p\n", + ns->msg_ctlmni, ns); +} + void msg_init_ns(struct ipc_namespace *ns) { ns->msg_ctlmax = MSGMAX; ns->msg_ctlmnb = MSGMNB; - ns->msg_ctlmni = MSGMNI; + + recompute_msgmni(ns); + atomic_set(&ns->msg_bytes, 0); atomic_set(&ns->msg_hdrs, 0); ipc_init_ids(&ns->ids[IPC_MSG_IDS]); |