linux/include/uapi
Manfred Spraul 0050ee059f ipc/msg: increase MSGMNI, remove scaling
SysV can be abused to allocate locked kernel memory.  For most systems, a
small limit doesn't make sense, see the discussion with regards to SHMMAX.

Therefore: increase MSGMNI to the maximum supported.

And: If we ignore the risk of locking too much memory, then an automatic
scaling of MSGMNI doesn't make sense.  Therefore the logic can be removed.

The code preserves auto_msgmni to avoid breaking any user space applications
that expect that the value exists.

Notes:
1) If an administrator must limit the memory allocations, then he can set
MSGMNI as necessary.

Or he can disable sysv entirely (as e.g. done by Android).

2) MSGMAX and MSGMNB are intentionally not increased, as these values are used
to control latency vs. throughput:
If MSGMNB is large, then msgsnd() just returns and more messages can be queued
before a task switch to a task that calls msgrcv() is forced.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Rafael Aquini <aquini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 12:42:52 -08:00
..
asm-generic syscalls: implement execveat() system call 2014-12-13 12:42:51 -08:00
drm drm/exynos: use drm generic mmap interface 2014-09-20 01:00:13 +09:00
linux ipc/msg: increase MSGMNI, remove scaling 2014-12-13 12:42:52 -08:00
misc cxl: Add documentation for userspace APIs 2014-10-08 20:16:19 +11:00
mtd mtd: lpddr: add driver for LPDDR2-NVM PCM memories 2014-05-20 17:45:17 -07:00
rdma Merge branches 'core', 'cxgb4', 'ipoib', 'iser', 'iwcm', 'mad', 'misc', 'mlx4', 'mlx5', 'ocrdma' and 'srp' into for-next 2014-08-14 08:58:04 -07:00
scsi
sound ALSA: oxfw: Add hwdep interface 2014-12-10 10:50:00 +01:00
video
xen
Kbuild cxl: Add userspace header file 2014-10-08 20:15:57 +11:00