Re: cpuid_t typedef? (was Re: Processor cores not properly detected/activated?)
On 30 May 2014 07:57, John Baldwin wrote: >> Ugh. Ok. I was too deep in the trenches of device drivers and other >> ancillary things doing bad things to char/short with cpu ids when >> walking things. I totally missed kinfo_proc. >> >> I'll go think about it a bit more. > > It shouldn't be too hard to to handle kinfo_proc. pf is another case. It > might be nice to have a way to auto-compute the right number of bits to > reserve based on MAXCPU. *nod* ok. Let me go and start sprinkling things around. -a ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: cpuid_t typedef? (was Re: Processor cores not properly detected/activated?)
On Thursday, May 29, 2014 5:46:05 pm Adrian Chadd wrote: > On 29 May 2014 14:29, John Baldwin wrote: > > On Thursday, May 29, 2014 5:09:05 pm Adrian Chadd wrote: > >> On 29 May 2014 13:18, John Baldwin wrote: > >> > >> >> anyway. Besides all of this - I'm thinking of just introducing: > >> >> > >> >> typedef uint32_t cpuid_t; > >> >> > >> >> .. then once we've converted all the users, we can make NOCPU > >> >> something other than 255 (which is the other limiting factor here..) > >> >> > >> >> Any objections? > >> > > >> > This one is a bit harder as you'll have to do shims for kinfo_proc, but > >> > I think this is fine. You could also just use u_int, but a new foo_t > >> > isn't that bad I guess. > >> > >> I don't think I'd modify any userland-facing ABI/KBI's just yet. I'm > >> just worried that 11.0-REL will come out before we have made a decent > >> inroads into this and we _can't_ support > 254 CPUs. > > > > Eh, that's one of the biggies to do actually. Kind of pointless to > > update td_oncpu/lastcpu and not fix kinfo_proc at the same time. You'll > > just have to add new int fields and populate the old ones with sane values > > for CPUs < 255. > > Ugh. Ok. I was too deep in the trenches of device drivers and other > ancillary things doing bad things to char/short with cpu ids when > walking things. I totally missed kinfo_proc. > > I'll go think about it a bit more. It shouldn't be too hard to to handle kinfo_proc. pf is another case. It might be nice to have a way to auto-compute the right number of bits to reserve based on MAXCPU. -- John Baldwin ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: cpuid_t typedef? (was Re: Processor cores not properly detected/activated?)
On 29 May 2014 14:29, John Baldwin wrote: > On Thursday, May 29, 2014 5:09:05 pm Adrian Chadd wrote: >> On 29 May 2014 13:18, John Baldwin wrote: >> >> >> anyway. Besides all of this - I'm thinking of just introducing: >> >> >> >> typedef uint32_t cpuid_t; >> >> >> >> .. then once we've converted all the users, we can make NOCPU >> >> something other than 255 (which is the other limiting factor here..) >> >> >> >> Any objections? >> > >> > This one is a bit harder as you'll have to do shims for kinfo_proc, but >> > I think this is fine. You could also just use u_int, but a new foo_t >> > isn't that bad I guess. >> >> I don't think I'd modify any userland-facing ABI/KBI's just yet. I'm >> just worried that 11.0-REL will come out before we have made a decent >> inroads into this and we _can't_ support > 254 CPUs. > > Eh, that's one of the biggies to do actually. Kind of pointless to > update td_oncpu/lastcpu and not fix kinfo_proc at the same time. You'll > just have to add new int fields and populate the old ones with sane values > for CPUs < 255. Ugh. Ok. I was too deep in the trenches of device drivers and other ancillary things doing bad things to char/short with cpu ids when walking things. I totally missed kinfo_proc. I'll go think about it a bit more. -a ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: cpuid_t typedef? (was Re: Processor cores not properly detected/activated?)
On Thursday, May 29, 2014 5:09:05 pm Adrian Chadd wrote: > On 29 May 2014 13:18, John Baldwin wrote: > > >> anyway. Besides all of this - I'm thinking of just introducing: > >> > >> typedef uint32_t cpuid_t; > >> > >> .. then once we've converted all the users, we can make NOCPU > >> something other than 255 (which is the other limiting factor here..) > >> > >> Any objections? > > > > This one is a bit harder as you'll have to do shims for kinfo_proc, but > > I think this is fine. You could also just use u_int, but a new foo_t > > isn't that bad I guess. > > I don't think I'd modify any userland-facing ABI/KBI's just yet. I'm > just worried that 11.0-REL will come out before we have made a decent > inroads into this and we _can't_ support > 254 CPUs. Eh, that's one of the biggies to do actually. Kind of pointless to update td_oncpu/lastcpu and not fix kinfo_proc at the same time. You'll just have to add new int fields and populate the old ones with sane values for CPUs < 255. -- John Baldwin ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: cpuid_t typedef? (was Re: Processor cores not properly detected/activated?)
On 29 May 2014 13:18, John Baldwin wrote: >> anyway. Besides all of this - I'm thinking of just introducing: >> >> typedef uint32_t cpuid_t; >> >> .. then once we've converted all the users, we can make NOCPU >> something other than 255 (which is the other limiting factor here..) >> >> Any objections? > > This one is a bit harder as you'll have to do shims for kinfo_proc, but > I think this is fine. You could also just use u_int, but a new foo_t > isn't that bad I guess. I don't think I'd modify any userland-facing ABI/KBI's just yet. I'm just worried that 11.0-REL will come out before we have made a decent inroads into this and we _can't_ support > 254 CPUs. -a ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: cpuid_t typedef? (was Re: Processor cores not properly detected/activated?)
On Thursday, May 29, 2014 4:05:49 pm Adrian Chadd wrote: > On 29 May 2014 11:44, John Baldwin wrote: > > On Thursday, May 29, 2014 2:24:45 pm Adrian Chadd wrote: > >> On 29 May 2014 10:18, John Baldwin wrote: > >> > >> >> > It costs wired memory to increase it for the kernel. The userland > >> >> > set size > >> >> > can be increased rather arbitrarily, so we don't need to make it but > >> >> > so large > >> >> > as it is easy to bump later (even with a branch). > >> >> > >> >> Well, what about making the API/KBI use cpuset_t pointers for things > >> >> rather than including it as a bitmask? Do you think there'd be a > >> >> noticable performance overhead for the bits where it's indirecting > >> >> through a pointer to get to the bitmask data? > >> > > >> > The wired memory is not due to cpuset_t. The wired memory usage is due > >> > to things > >> > that do 'struct foo foo_bits[MAXCPU]'. The KBI issues I mentioned above > >> > are > >> > 'struct rmlock' (so now you want any rmlock users to malloc space, or you > >> > want rmlock_init() call malloc? (that seems like a bad idea)). The > >> > other one > >> > is smp_rendezvous. Plus, it's not just a pointer, you really need a > >> > (pointer, > >> > size_t) tuple similar to what cpuset_getaffinity(), etc. use. > >> > >> Why would calling malloc be a problem? Except for the initial setup of > >> things, anything dynamically allocating structs with embedded things > >> like rmlocks are already dynamically allocating them via malloc or > >> uma. > >> > >> There's a larger fundamental problem with malloc, fragmentation and > >> getting the required larger allocations for things. But even a 4096 > >> CPU box would require a 512 byte malloc. That shouldn't be that hard > >> to do. It'd just be from some memory that isn't close to the rest of > >> the lock state. > > > > Other similar APIs like mtx_init() don't call malloc(), so it would be > > unusual behavior. However, we have several other problems before we can > > move beyond 256 anyway (like pf). > > Maybe behaviour has to change over time. :( > > anyway. Besides all of this - I'm thinking of just introducing: > > typedef uint32_t cpuid_t; > > .. then once we've converted all the users, we can make NOCPU > something other than 255 (which is the other limiting factor here..) > > Any objections? This one is a bit harder as you'll have to do shims for kinfo_proc, but I think this is fine. You could also just use u_int, but a new foo_t isn't that bad I guess. -- John Baldwin ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
cpuid_t typedef? (was Re: Processor cores not properly detected/activated?)
On 29 May 2014 11:44, John Baldwin wrote: > On Thursday, May 29, 2014 2:24:45 pm Adrian Chadd wrote: >> On 29 May 2014 10:18, John Baldwin wrote: >> >> >> > It costs wired memory to increase it for the kernel. The userland set >> >> > size >> >> > can be increased rather arbitrarily, so we don't need to make it but so >> >> > large >> >> > as it is easy to bump later (even with a branch). >> >> >> >> Well, what about making the API/KBI use cpuset_t pointers for things >> >> rather than including it as a bitmask? Do you think there'd be a >> >> noticable performance overhead for the bits where it's indirecting >> >> through a pointer to get to the bitmask data? >> > >> > The wired memory is not due to cpuset_t. The wired memory usage is due to >> > things >> > that do 'struct foo foo_bits[MAXCPU]'. The KBI issues I mentioned above >> > are >> > 'struct rmlock' (so now you want any rmlock users to malloc space, or you >> > want rmlock_init() call malloc? (that seems like a bad idea)). The other >> > one >> > is smp_rendezvous. Plus, it's not just a pointer, you really need a >> > (pointer, >> > size_t) tuple similar to what cpuset_getaffinity(), etc. use. >> >> Why would calling malloc be a problem? Except for the initial setup of >> things, anything dynamically allocating structs with embedded things >> like rmlocks are already dynamically allocating them via malloc or >> uma. >> >> There's a larger fundamental problem with malloc, fragmentation and >> getting the required larger allocations for things. But even a 4096 >> CPU box would require a 512 byte malloc. That shouldn't be that hard >> to do. It'd just be from some memory that isn't close to the rest of >> the lock state. > > Other similar APIs like mtx_init() don't call malloc(), so it would be > unusual behavior. However, we have several other problems before we can > move beyond 256 anyway (like pf). Maybe behaviour has to change over time. :( anyway. Besides all of this - I'm thinking of just introducing: typedef uint32_t cpuid_t; .. then once we've converted all the users, we can make NOCPU something other than 255 (which is the other limiting factor here..) Any objections? -a ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
