Eric Lee / smarc-ti-linux-kernel

30 Jul, 2014

1 commit

  • 728dba3a3   namespaces: Use task_lock and not rcu to protect nsproxy ... Browse Code »

    The synchronous syncrhonize_rcu in switch_task_namespaces makes setns
    a sufficiently expensive system call that people have complained.

    Upon inspect nsproxy no longer needs rcu protection for remote reads.
    remote reads are rare. So optimize for same process reads and write
    by switching using rask_lock instead.

    This yields a simpler to understand lock, and a faster setns system call.

    In particular this fixes a performance regression observed
    by Rafael David Tinoco .

    This is effectively a revert of Pavel Emelyanov's commit
    cf7b708c8d1d7a27736771bcf4c457b332b0f818 Make access to task's nsproxy lighter
    from 2007. The race this originialy fixed no longer exists as
    do_notify_parent uses task_active_pid_ns(parent) instead of
    parent->nsproxy.

    Signed-off-by: "Eric W. Biederman"

    Eric W. Biederman
     

02 Apr, 2014

1 commit

24 Jan, 2014

1 commit

25 Oct, 2013

1 commit

14 Jul, 2012

1 commit

30 May, 2012

1 commit

  • 962830df3   brlocks/lglocks: API cleanups ... Browse Code »

    lglocks and brlocks are currently generated with some complicated macros
    in lglock.h. But there's no reason to not just use common utility
    functions and put all the data into a common data structure.

    In preparation, this patch changes the API to look more like normal
    function calls with pointers, not magic macros.

    The patch is rather large because I move over all users in one go to keep
    it bisectable. This impacts the VFS somewhat in terms of lines changed.
    But no actual behaviour change.

    [akpm@linux-foundation.org: checkpatch fixes]
    Signed-off-by: Andi Kleen
    Cc: Al Viro
    Cc: Rusty Russell
    Signed-off-by: Andrew Morton
    Signed-off-by: Rusty Russell
    Signed-off-by: Al Viro

    Andi Kleen
     

07 Jan, 2012

4 commits

04 Jan, 2012

1 commit