[PATCH 1/8] Scaling msgmni to the amount of lowmem
which I see has made its way in 2.6.26-rc
Your patch has the following change:
-#define MSGPOOL (MSGMNI*MSGMNB/1024) /* size in kilobytes of message pool */
+#define MSGPOOL (MSGMNI * MSGMNB) /* size in bytes of message pool */
Since this constitutes a kernel-userland interface change, so please
do CC me, so that I can change the man pages if needed.
The man page (http://www.kernel.org/doc/man-pages/online/pages/man2/msgctl.2.html)
does indeed say that msgpool is "unused". But that meant "unused by
the kernel" (sorry -- I probably should have worded that text better).
And, as you spotted, the page also wrongly said the value is in
However, making this change affects the ABI. A userspace application
that was previously using msgctl(IPC_INFO) to retrieve the msgpool
field will be affected by the factor-of-1024 change. I strongly
suspect that there no such applications, or certainly none that care
(since this value is unused by the kernel). But was there a reason
for making this change, aside from the fact that the code and the man
page didn't agree?