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Neither the CPU nor MM CID can change without going through > a context switch. > > Collapse them all into a single boolean which simplifies the code a lot and > remove the pointless invocations which have been sprinkled all over the > place for no value. > > Signed-off-by: Thomas Gleixner > Cc: Peter Zijlstra > Cc: Mathieu Desnoyers > Cc: "Paul E. McKenney" > Cc: Boqun Feng > > --- > V2: Reduce it to the sched switch event. > --- > fs/exec.c | 2 - > include/linux/rseq.h | 66 +++++++++------------------------------------- > include/linux/sched.h | 10 +++--- > include/uapi/linux/rseq.h | 21 ++++---------- > kernel/rseq.c | 28 +++++++++++-------- > kernel/sched/core.c | 5 --- > kernel/sched/membarrier.c | 8 ++--- > 7 files changed, 48 insertions(+), 92 deletions(-) > --- > [...] > --- a/include/uapi/linux/rseq.h > +++ b/include/uapi/linux/rseq.h > @@ -114,20 +114,13 @@ struct rseq { > /* > * Restartable sequences flags field. > * > - * This field should only be updated by the thread which > - * registered this data structure. Read by the kernel. > - * Mainly used for single-stepping through rseq critical sections > - * with debuggers. > - * > - * - RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT > - * Inhibit instruction sequence block restart on preemption > - * for this thread. > - * - RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL > - * Inhibit instruction sequence block restart on signal > - * delivery for this thread. > - * - RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE > - * Inhibit instruction sequence block restart on migration for > - * this thread. > + * This field was initialy intended to allow event masking for for initialy -> initially for for -> for Other than those nits: Reviewed-by: Mathieu Desnoyers -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com