On Sun, Oct 25, 2015 at 11:47:04AM +0100, Florian Weimer wrote: > On 10/25/2015 11:41 AM, Theodore Ts'o wrote: > > On Sun, Oct 25, 2015 at 10:33:32AM +0100, Ingo Molnar wrote: > >> > >> Hm, that's weird - all our sched_*() system call APIs that set task scheduling > >> priorities are fundamentally per thread, not per process. Same goes for the old > >> sys_nice() interface. The scheduler has no real notion of 'process', and certainly > >> not at the system call level. > >> > > > > I suspect the main issue is that the games programmers were trying to > > access it via libc / pthreads, which hides a lot of the power > > available at the raw syscall level. This is probably more of a > > "tutorial needed for userspace programmers" issue, at a guess. > > If this refers to the lack of exposure of thread IDs in glibc, we are > willing to change that on glibc side. The discussion has progressed to > the point where it is now about the question whether it should be part > of the GNU API (like sched_setaffinity), or live in glibc as a > Linux-specific extension (like sched_getcpu). More input is certainly > welcome. Well, I was thinking we could just teach them to use "syscall(SYS_gettid)". On a different subject, I'm going to start telling people to use "syscall(SYS_getrandom)", since I think that's going to be easier than having asking people to change their Makefiles to link against some Linux-specific library, but that's a different debate, and I recognize the glibc folks aren't willing to bend on that one. Cheers, - Ted -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
