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If cancel_job is not >>   * implemented, memory could leak. >> + * >> + * The scheduler fences timeline name is returned protected by the signaled >> + * status and RCU, so an RCU grace period is necessary between signaling the >> + * last scheduler fence and tearing down the scheduler who originated it. >>   */ > > The API user does not signal a "scheduler fence", typically. Are you > referring to the hardware-fence? Yes, of course. Signaling the HW fence then causes the scheduler fence to signal as well. > > The user must signal all hardware-fences, which will cause all > finished-fences (which are at the root of the addressed problem) to be > signaled. > > So what you probably want to say is "The user must wait one RCU grace > period between signaling the last hardware-fence and calling this > function because …". k, going to fix that. Thanks, Christian. > > > P.