1. 13 Dec, 2014 1 commit
    • Manfred Spraul's avatar
      ipc/msg: increase MSGMNI, remove scaling · 0050ee05
      Manfred Spraul authored
      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: 's avatarManfred Spraul <manfred@colorfullife.com>
      Cc: Davidlohr Bueso <dave@stgolabs.net>
      Cc: Rafael Aquini <aquini@redhat.com>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      0050ee05
  2. 12 Mar, 2010 1 commit
    • Christoph Hellwig's avatar
      Add generic sys_ipc wrapper · baed7fc9
      Christoph Hellwig authored
      Add a generic implementation of the ipc demultiplexer syscall.  Except for
      s390 and sparc64 all implementations of the sys_ipc are nearly identical.
      
      There are slight differences in the types of the parameters, where mips
      and powerpc as the only 64-bit architectures with sys_ipc use unsigned
      long for the "third" argument as it gets casted to a pointer later, while
      it traditionally is an "int" like most other paramters.  frv goes even
      further and uses unsigned long for all parameters execept for "ptr" which
      is a pointer type everywhere.  The change from int to unsigned long for
      "third" and back to "int" for the others on frv should be fine due to the
      in-register calling conventions for syscalls (we already had a similar
      issue with the generic sys_ptrace), but I'd prefer to have the arch
      maintainers looks over this in details.
      
      Except for that h8300, m68k and m68knommu lack an impplementation of the
      semtimedop sub call which this patch adds, and various architectures have
      gets used - at least on i386 it seems superflous as the compat code on
      x86-64 and ia64 doesn't even bother to implement it.
      
      [akpm@linux-foundation.org: add sys_ipc to sys_ni.c]
      Signed-off-by: 's avatarChristoph Hellwig <hch@lst.de>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Jeff Dike <jdike@addtoit.com>
      Cc: Hirokazu Takata <takata@linux-m32r.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@elte.hu>
      Reviewed-by: 's avatarH. Peter Anvin <hpa@zytor.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: "Luck, Tony" <tony.luck@intel.com>
      Cc: James Morris <jmorris@namei.org>
      Cc: Andreas Schwab <schwab@linux-m68k.org>
      Acked-by: 's avatarJesper Nilsson <jesper.nilsson@axis.com>
      Acked-by: 's avatarRussell King <rmk+kernel@arm.linux.org.uk>
      Acked-by: 's avatarDavid Howells <dhowells@redhat.com>
      Acked-by: 's avatarKyle McMartin <kyle@mcmartin.ca>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      baed7fc9
  3. 07 Apr, 2009 1 commit
  4. 29 Apr, 2008 2 commits
    • Nadia Derbey's avatar
      ipc: recompute msgmni on ipc namespace creation/removal · e2c284d8
      Nadia Derbey authored
      Introduce a notification mechanism that aims at recomputing msgmni each time
      an ipc namespace is created or removed.
      
      The ipc namespace notifier chain already defined for memory hotplug management
      is used for that purpose too.
      
      Each time a new ipc namespace is allocated or an existing ipc namespace is
      removed, the ipcns notifier chain is notified.  The callback routine for each
      registered ipc namespace is then activated in order to recompute msgmni for
      that namespace.
      Signed-off-by: 's avatarNadia Derbey <Nadia.Derbey@bull.net>
      Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
      Cc: Matt Helsley <matthltc@us.ibm.com>
      Cc: Mingming Cao <cmm@us.ibm.com>
      Cc: Pierre Peiffer <pierre.peiffer@bull.net>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      e2c284d8
    • Nadia Derbey's avatar
      ipc: recompute msgmni on memory add / remove · b6b337ad
      Nadia Derbey authored
      Introduce the registration of a callback routine that recomputes msg_ctlmni
      upon memory add / remove.
      
      A single notifier block is registered in the hotplug memory chain for all the
      ipc namespaces.
      
      Since the ipc namespaces are not linked together, they have their own
      notification chain: one notifier_block is defined per ipc namespace.
      
      Each time an ipc namespace is created (removed) it registers (unregisters) its
      notifier block in (from) the ipcns chain.  The callback routine registered in
      the memory chain invokes the ipcns notifier chain with the IPCNS_LOWMEM event.
       Each callback routine registered in the ipcns namespace, in turn, recomputes
      msgmni for the owning namespace.
      Signed-off-by: 's avatarNadia Derbey <Nadia.Derbey@bull.net>
      Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
      Cc: Matt Helsley <matthltc@us.ibm.com>
      Cc: Mingming Cao <cmm@us.ibm.com>
      Cc: Pierre Peiffer <pierre.peiffer@bull.net>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      b6b337ad
  5. 08 Feb, 2008 1 commit
    • Pavel Emelyanov's avatar
      namespaces: move the IPC namespace under IPC_NS option · ae5e1b22
      Pavel Emelyanov authored
      Currently the IPC namespace management code is spread over the ipc/*.c files.
      I moved this code into ipc/namespace.c file which is compiled out when needed.
      
      The linux/ipc_namespace.h file is used to store the prototypes of the
      functions in namespace.c and the stubs for NAMESPACES=n case.  This is done
      so, because the stub for copy_ipc_namespace requires the knowledge of the
      CLONE_NEWIPC flag, which is in sched.h.  But the linux/ipc.h file itself in
      included into many many .c files via the sys.h->sem.h sequence so adding the
      sched.h into it will make all these .c depend on sched.h which is not that
      good.  On the other hand the knowledge about the namespaces stuff is required
      in 4 .c files only.
      
      Besides, this patch compiles out some auxiliary functions from ipc/sem.c,
      msg.c and shm.c files.  It turned out that moving these functions into
      namespaces.c is not that easy because they use many other calls and macros
      from the original file.  Moving them would make this patch complicated.  On
      the other hand all these functions can be consolidated, so I will send a
      separate patch doing this a bit later.
      Signed-off-by: 's avatarPavel Emelyanov <xemul@openvz.org>
      Acked-by: 's avatarSerge Hallyn <serue@us.ibm.com>
      Cc: Cedric Le Goater <clg@fr.ibm.com>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Cc: Herbert Poetzl <herbert@13thfloor.at>
      Cc: Kirill Korotaev <dev@sw.ru>
      Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      ae5e1b22
  6. 14 Feb, 2007 1 commit
  7. 16 Apr, 2005 1 commit
    • Linus Torvalds's avatar
      Linux-2.6.12-rc2 · 1da177e4
      Linus Torvalds authored
      Initial git repository build. I'm not bothering with the full history,
      even though we have it. We can create a separate "historical" git
      archive of that later if we want to, and in the meantime it's about
      3.2GB when imported into git - space that would just make the early
      git days unnecessarily complicated, when we don't have a lot of good
      infrastructure for it.
      
      Let it rip!
      1da177e4