• Stanislav Kinsbursky's avatar
    ipc: add sysctl to specify desired next object id · 03f59566
    Stanislav Kinsbursky authored
    Add 3 new variables and sysctls to tune them (by one "next_id" variable
    for messages, semaphores and shared memory respectively).  This variable
    can be used to set desired id for next allocated IPC object.  By default
    it's equal to -1 and old behaviour is preserved.  If this variable is
    non-negative, then desired idr will be extracted from it and used as a
    start value to search for free IDR slot.
    
    Notes:
    
    1) this patch doesn't guarantee that the new object will have desired
       id.  So it's up to user space how to handle new object with wrong id.
    
    2) After a sucessful id allocation attempt, "next_id" will be set back
       to -1 (if it was non-negative).
    
    [akpm@linux-foundation.org: checkpatch fixes]
    Signed-off-by: default avatarStanislav Kinsbursky <skinsbursky@parallels.com>
    Cc: Serge Hallyn <serge.hallyn@canonical.com>
    Cc: "Eric W. Biederman" <ebiederm@xmission.com>
    Cc: Pavel Emelyanov <xemul@parallels.com>
    Cc: Al Viro <viro@zeniv.linux.org.uk>
    Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
    Cc: Michael Kerrisk <mtk.manpages@gmail.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    03f59566
util.h 5.33 KB