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Can you elaborate on a concrete use-case justifying adding this ? Thanks, Mathieu > > Signed-off-by: Dylan Yudaken > --- > kernel/sched/membarrier.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c > index 809194cd779f..def6d4094ad6 100644 > --- a/kernel/sched/membarrier.c > +++ b/kernel/sched/membarrier.c > @@ -595,7 +595,9 @@ static int membarrier_get_registrations(void) > * contains the CPU on which to interrupt (= restart) > * the RSEQ critical section. > * @cpu_id: if @flags == MEMBARRIER_CMD_FLAG_CPU, indicates the cpu on which > - * RSEQ CS should be interrupted (@cmd must be > + * RSEQ CS should be interrupted (@cmd must be one of > + * MEMBARRIER_CMD_PRIVATE_EXPEDITED, > + * MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_CORE, > * MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ). > * > * If this system call is not implemented, -ENOSYS is returned. If the > @@ -625,6 +627,8 @@ static int membarrier_get_registrations(void) > SYSCALL_DEFINE3(membarrier, int, cmd, unsigned int, flags, int, cpu_id) > { > switch (cmd) { > + case MEMBARRIER_CMD_PRIVATE_EXPEDITED: > + case MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_CORE: > case MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ: > if (unlikely(flags && flags != MEMBARRIER_CMD_FLAG_CPU)) > return -EINVAL; -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com