Messages in this thread | | | Date | Wed, 21 Nov 2018 23:34:53 +0100 | From | Andrea Parri <> | Subject | [Question] atomic_fetch_andnot() in nohz_idle_balance() |
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Hi,
The comment for the atomic_fetch_andnot() in nohz_idle_balance() says:
"barrier, pairs with nohz_balance_enter_idle(), ensures ..."
which, well, does sound a note of warning... ;-)
I see that nohz_balance_enter_idle() has an smp_mb__after_atomic() but the comment for the latter suggests that this barrier is pairing with the smp_mb() in _nohz_idle_balance().
So, what is the intended pairing barrier for the atomic_fetch_andnot()? what (which memory accesses) do you want "to order" here?
Thanks, Andrea
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