On 1/29/19 9:26 AM, Arnd Bergmann wrote: > On Tue, Jan 29, 2019 at 5:19 PM Jens Axboe <axboe@xxxxxxxxx> wrote: >> On 1/29/19 9:18 AM, Arnd Bergmann wrote: >>> On Tue, Jan 29, 2019 at 4:20 PM Jens Axboe <axboe@xxxxxxxxx> wrote: >>>> That's good info. I am currently using set_user_sigmask() for it. >>>> I'd really like to avoid having to pass in a sigset_t size for the >>>> system call, however. >>> >>> I really wouldn't do it, given that all other signal handling interfaces >>> are prepared for longer signal masks. You /could/ probably extend >>> it later with a flags bit to signify a longer mask instead of using >>> the entire register to hold the bit length, it just seems really >>> inconsistent with all other system calls. >> >> Damnit! OK, I'll keep what I currently have then. > > As long as you stay within the 6-argument syscall contraints, > the cost of passing the length is basically free, right? > > Is there anything else you are worried about? My main worry is not the extra argument, more that we're at capacity for the system call. If we wanted to add a timeout parameter, then we'd need to bundle them up, which sucks. But I think we're fine, I'll go with what I have. -- Jens Axboe
