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Diffstat (limited to 'ipc/msg.c')
-rw-r--r--ipc/msg.c37
1 files changed, 36 insertions, 1 deletions
diff --git a/ipc/msg.c b/ipc/msg.c
index 805ee08ec8b..9e7211122e2 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]);