| Message ID | 20170718103429.25020-8-sergey.dyasli@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 07/18/2017 11:34 AM, Sergey Dyasli wrote: > np2m maintenance is required for a nested vcpu during scheduling: > > 1. On schedule-out: clear pCPU's bit in p2m->dirty_cpumask > to prevent useless IPIs. > > 2. On schedule-in: check if np2m is up to date and wasn't flushed. > > Signed-off-by: Sergey Dyasli <sergey.dyasli@citrix.com> > --- > xen/arch/x86/mm/p2m.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++ > xen/include/asm-x86/p2m.h | 3 +++ > 2 files changed, 55 insertions(+) > > diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c > index 3d65899b05..4b83d4a4f1 100644 > --- a/xen/arch/x86/mm/p2m.c > +++ b/xen/arch/x86/mm/p2m.c > @@ -1880,6 +1880,58 @@ p2m_get_p2m(struct vcpu *v) > return p2m_get_nestedp2m(v); > } > > +static void np2m_schedule(bool sched_out) > +{ > + struct nestedvcpu *nv = &vcpu_nestedhvm(current); > + struct p2m_domain *p2m; > + bool sched_in = !sched_out; > + > + if ( !nestedhvm_enabled(current->domain) || > + !nestedhvm_vcpu_in_guestmode(current) || > + !nestedhvm_paging_mode_hap(current) ) > + return; > + > + p2m = nv->nv_p2m; > + if ( p2m ) > + { > + bool np2m_valid; > + > + p2m_lock(p2m); > + np2m_valid = p2m->np2m_base == nhvm_vcpu_p2m_base(current) && > + nv->np2m_generation == p2m->np2m_generation; > + if ( sched_out && np2m_valid ) > + { > + /* > + * The np2m is up to date but this vCPU will no longer use it, > + * which means there are no reasons to send a flush IPI. > + */ > + cpumask_clear_cpu(current->processor, p2m->dirty_cpumask); > + } > + else if ( sched_in ) > + { > + if ( !np2m_valid ) > + { > + /* This vCPU's np2m was flushed while it was not runnable */ > + hvm_asid_flush_core(); > + vcpu_nestedhvm(current).nv_p2m = NULL; > + } > + else > + cpumask_set_cpu(current->processor, p2m->dirty_cpumask); > + } > + p2m_unlock(p2m); > + } > +} This level of sharing seems a tad excessive to me; but if we're going to do it, I think it would be more clear if the callers called a function called np2m_schedule() with `dir`, then define things something like this: #define NP2M_SCHEDLE_IN 0 #define NP2M_SCHEDLE_OUT 1 -George
diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c index 3d65899b05..4b83d4a4f1 100644 --- a/xen/arch/x86/mm/p2m.c +++ b/xen/arch/x86/mm/p2m.c @@ -1880,6 +1880,58 @@ p2m_get_p2m(struct vcpu *v) return p2m_get_nestedp2m(v); } +static void np2m_schedule(bool sched_out) +{ + struct nestedvcpu *nv = &vcpu_nestedhvm(current); + struct p2m_domain *p2m; + bool sched_in = !sched_out; + + if ( !nestedhvm_enabled(current->domain) || + !nestedhvm_vcpu_in_guestmode(current) || + !nestedhvm_paging_mode_hap(current) ) + return; + + p2m = nv->nv_p2m; + if ( p2m ) + { + bool np2m_valid; + + p2m_lock(p2m); + np2m_valid = p2m->np2m_base == nhvm_vcpu_p2m_base(current) && + nv->np2m_generation == p2m->np2m_generation; + if ( sched_out && np2m_valid ) + { + /* + * The np2m is up to date but this vCPU will no longer use it, + * which means there are no reasons to send a flush IPI. + */ + cpumask_clear_cpu(current->processor, p2m->dirty_cpumask); + } + else if ( sched_in ) + { + if ( !np2m_valid ) + { + /* This vCPU's np2m was flushed while it was not runnable */ + hvm_asid_flush_core(); + vcpu_nestedhvm(current).nv_p2m = NULL; + } + else + cpumask_set_cpu(current->processor, p2m->dirty_cpumask); + } + p2m_unlock(p2m); + } +} + +void np2m_schedule_out(void) +{ + np2m_schedule(true); +} + +void np2m_schedule_in(void) +{ + np2m_schedule(false); +} + unsigned long paging_gva_to_gfn(struct vcpu *v, unsigned long va, uint32_t *pfec) diff --git a/xen/include/asm-x86/p2m.h b/xen/include/asm-x86/p2m.h index eedc7fd412..801a11a960 100644 --- a/xen/include/asm-x86/p2m.h +++ b/xen/include/asm-x86/p2m.h @@ -370,6 +370,9 @@ struct p2m_domain *p2m_get_nestedp2m(struct vcpu *v); */ struct p2m_domain *p2m_get_p2m(struct vcpu *v); +void np2m_schedule_out(void); +void np2m_schedule_in(void); + static inline bool_t p2m_is_hostp2m(const struct p2m_domain *p2m) { return p2m->p2m_class == p2m_host;
np2m maintenance is required for a nested vcpu during scheduling: 1. On schedule-out: clear pCPU's bit in p2m->dirty_cpumask to prevent useless IPIs. 2. On schedule-in: check if np2m is up to date and wasn't flushed. Signed-off-by: Sergey Dyasli <sergey.dyasli@citrix.com> --- xen/arch/x86/mm/p2m.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++ xen/include/asm-x86/p2m.h | 3 +++ 2 files changed, 55 insertions(+)