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Not in the atomic-SRCU. Unless we do something like this on > top? It is true for the atomic readers as well. Without CONFIG_NEED_SRCU_NMI_SAFE, include/linux/srcu.h defines __srcu_read_lock_nmisafe() as an inline that calls __srcu_read_lock(), and the same for unlock. So x86 keeps this_cpu_inc() and smp_mb(). Your diff selects the same functions by hand. Only the architectures that select NEED_SRCU_NMI_SAFE get the atomic increments. > I set a test running (*without* the above). Thanks! Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com