RE: [PATCH] Don't apply for write lock on tasklist_lock if parentdoesn't ptrace other processes

[Kleen, Andi]

> The only difference is that we are doing the function call +
> list_empty()
> under tasklist, just a few instructions compared to "do a lot more
> work"
> in forget_original_parent().
> 
> How this can make the 2% difference ? This looks like a noise to me,
> or do you think I missed something?

It could be a cache miss or something like that. Instructions are not
all the same cost. Only detailed profiling with different performance counters
could give you more information.

-Andi

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