----- Original Message ----- > On 08/26/2013 03:46 PM, Andrew Jones wrote: > >>> Is this patch still necessary? I thought that dropping the > >>> > > numa_num_configured_nodes() calls from patch 8/12 got rid > >>> > > of the need for this library. Maybe I missed other uses? > >> > > >> > Yes, in 08/12 we also use mbind(), > > You don't need a whole library for mbind(), it's a syscall. See syscall(2). > > > >> > and in 09/12 we use max_numa_node(). > > Really? I didn't see it there. And anyway, that goes back to our discussion > > about setting qemu's MAX_NODES to whatever we think qemu should support, > > and then just checking that we don't blow that limit whenever reading > > host node info, i.e. > > > > maxnode = 0; > > while (host_nodes[maxnode] && maxnode < MAX_NODES) > > node_read(&info[maxnode++]); > > > > type of a thing. > > > > And, if there's a place you really need to know the current online number > > of host nodes, then, like I said earlier, you should just go to sysfs > > yourself. libnuma:numa_max_node() returns an int that it only initializes > > at library load time, so it's not going to adapt to onlining/offlining. > > OK, thank you. > Then I should define MPOL_* macros in QEMU and use mbind(2) syscall directly, > right?
Hmm, yeah, that's too bad that numaif.h is part of libnuma, and not a more general lib. Whether or not we want to redefine those symbols within qemu, in order to avoid the dependency on installing numactl-devel, isn't something I can answer. That's a better question for Anthony. Anthony? Paolo, any opinions? Maybe we should pick up uapi/linux/mempolicy.h with the linux-header synch script? thanks, drew > > Thanks, > Wanlong Gao > > > > > drew > > > >
