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    SubjectRe: [PATCH 1/2] x86: Cleanup TIF value gaps in shift range
    On Mon, 18 Oct 2010, Frederic Weisbecker wrote:

    > 9, 19 and 26 values are missing from the TIF shift range, probably
    > due to flags that were removed by the past. Now repack the range
    > so that we can quickly retrieve the remaining free shift slots.
    > But take care of keeping the seperation between high and low bits
    > as some masks are created on top of this boundary.

    What's the benefit of doing this?

    These flags are exported to userspace through SysRq-T, SysRq+W, the hung
    task detector, and the rcu stall detector, so there may be external
    dependencies testing for these bits.

    We use this to look for TIF_MEMDIE to determine whether an oom killed task
    has failed to exit and becomes hung after having access to memory
    reserves, and that's one of the bits you've changed here.

     \ /
      Last update: 2010-10-18 22:51    [W:0.021 / U:3.888 seconds]
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