On Fri, 2015-06-12 at 16:32 +0800, Chen Baozi wrote: > From: Chen Baozi <baoz...@gmail.com> > > Each vGIC driver supports different maximum numbers of vCPU. For > example, GICv2 is limited to 8 vCPUs, while GICv3 can support up > to 4096 vCPUs if we use both AFF0 and AFF1. Thus, domain_max_vcpus > should depend on not only MAX_VIRT_CPUS but also the version > of vGIC that the guest uses. > > Since evtchn_init would call domain_max_vcpus to allocate poll_mask > when the vgic_ops haven't been initialised yet, we make it return > MAX_VIRT_CPUS at that time. On ARM32, event channel doesn't need > to allocate the poll_mask because MAX_VIRT_CPUS < BITS_PER_LONG, > while allocating more memory (2 unsigned long rather than 1) only > for poll_mask on arm64 with GICv2 looks not so expensive. > > We didn't keep it as the old static inline form because it will break > compilation when access the member of struct domain: > > In file included from xen/include/xen/domain.h:6:0, > from xen/include/xen/sched.h:10, > from arm64/asm-offsets.c:10: > xen/include/asm/domain.h: In function ‘domain_max_vcpus’: > xen/include/asm/domain.h:266:10: error: dereferencing pointer to incomplete > type > if (d->arch.vgic.version == GIC_V2) > ^ > > Signed-off-by: Chen Baozi <baoz...@gmail.com>
Acked-by: Ian Campbell <ian.campb...@citrix.com> [...] > + * We use both AFF1 and AFF0 in (v)MPIDR. Thus, the max number of CPU > + * that can be supported is up to 4096(256*16) in theory. Please stick an " == " ......................^ here. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
