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\ > + set_bit(b, &flags); \ > + /* set_bit() does not imply a memory barrier */ \ > + smp_mb__after_atomic(); \ > + } This isn't needed, set_bit/test_bit are already atomic with themselves, we should not need to introduce release semantics. Please split this to one patch per variable Every variable should be evalulated to decide if we should hold the spinlock instead of relying on atomics. Jason