| Message ID | 20241230063051.3332332-1-Sergiy_Kibrik@epam.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [XEN,v1] xen: mem_access: conditionally compile vm_event.c & monitor.c | expand |
On Mon, 30 Dec 2024, Sergiy Kibrik wrote: > From: Stefano Stabellini <stefano.stabellini@amd.com> > > Extend coverage of CONFIG_MEM_ACCESS option and make the build of VM events > and monitoring support optional. > This is to reduce code size on Arm when this option isn't enabled. > > Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com> > Signed-off-by: Sergiy Kibrik <Sergiy_Kibrik@epam.com> I would add my reviewed-by but I wrote an early draft of this patch... That said, it looks OK to me. > --- > xen/arch/arm/Makefile | 4 ++-- > xen/arch/arm/vsmc.c | 3 ++- > xen/common/Makefile | 4 ++-- > xen/include/xen/monitor.h | 9 +++++++++ > xen/include/xen/vm_event.h | 14 +++++++++++--- > 5 files changed, 26 insertions(+), 8 deletions(-) > > diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile > index 43ab5e8f25..8903eb0bf2 100644 > --- a/xen/arch/arm/Makefile > +++ b/xen/arch/arm/Makefile > @@ -39,7 +39,7 @@ obj-$(CONFIG_LIVEPATCH) += livepatch.o > obj-$(CONFIG_LLC_COLORING) += llc-coloring.o > obj-$(CONFIG_MEM_ACCESS) += mem_access.o > obj-y += mm.o > -obj-y += monitor.o > +obj-$(CONFIG_MEM_ACCESS) += monitor.o > obj-y += p2m.o > obj-y += platform.o > obj-y += platform_hypercall.o > @@ -65,7 +65,7 @@ obj-$(CONFIG_VGICV2) += vgic-v2.o > obj-$(CONFIG_GICV3) += vgic-v3.o > obj-$(CONFIG_HAS_ITS) += vgic-v3-its.o > endif > -obj-y += vm_event.o > +obj-$(CONFIG_MEM_ACCESS) += vm_event.o > obj-y += vtimer.o > obj-$(CONFIG_SBSA_VUART_CONSOLE) += vpl011.o > obj-y += vsmc.o > diff --git a/xen/arch/arm/vsmc.c b/xen/arch/arm/vsmc.c > index 62d8117a12..1c13326bdf 100644 > --- a/xen/arch/arm/vsmc.c > +++ b/xen/arch/arm/vsmc.c > @@ -330,7 +330,8 @@ void do_trap_smc(struct cpu_user_regs *regs, const union hsr hsr) > } > > /* If monitor is enabled, let it handle the call. */ > - if ( current->domain->arch.monitor.privileged_call_enabled ) > + if ( IS_ENABLED(CONFIG_MEM_ACCESS) && > + current->domain->arch.monitor.privileged_call_enabled ) > rc = monitor_smc(); > > if ( rc == 1 ) > diff --git a/xen/common/Makefile b/xen/common/Makefile > index cba3b32733..e3c6a857ab 100644 > --- a/xen/common/Makefile > +++ b/xen/common/Makefile > @@ -54,7 +54,7 @@ obj-y += timer.o > obj-$(CONFIG_TRACEBUFFER) += trace.o > obj-y += version.o > obj-y += virtual_region.o > -obj-y += vm_event.o > +obj-$(CONFIG_MEM_ACCESS) += vm_event.o > obj-$(CONFIG_HAS_VMAP) += vmap.o > obj-y += vsprintf.o > obj-y += wait.o > @@ -68,7 +68,7 @@ obj-$(CONFIG_COMPAT) += $(addprefix compat/,domain.o memory.o multicall.o xlat.o > > ifneq ($(CONFIG_PV_SHIM_EXCLUSIVE),y) > obj-y += domctl.o > -obj-y += monitor.o > +obj-$(CONFIG_MEM_ACCESS) += monitor.o > obj-y += sysctl.o > endif > > diff --git a/xen/include/xen/monitor.h b/xen/include/xen/monitor.h > index 713d54f7c1..f1359abb94 100644 > --- a/xen/include/xen/monitor.h > +++ b/xen/include/xen/monitor.h > @@ -27,8 +27,17 @@ > struct domain; > struct xen_domctl_monitor_op; > > +#ifdef CONFIG_MEM_ACCESS > int monitor_domctl(struct domain *d, struct xen_domctl_monitor_op *mop); > void monitor_guest_request(void); > +#else > +static inline int monitor_domctl(struct domain *d, > + struct xen_domctl_monitor_op *mop) > +{ > + return -EINVAL; > +} > +static inline void monitor_guest_request(void) {} > +#endif > > int monitor_traps(struct vcpu *v, bool sync, vm_event_request_t *req); > > diff --git a/xen/include/xen/vm_event.h b/xen/include/xen/vm_event.h > index 9a86358b42..72e720e378 100644 > --- a/xen/include/xen/vm_event.h > +++ b/xen/include/xen/vm_event.h > @@ -50,9 +50,6 @@ struct vm_event_domain > unsigned int last_vcpu_wake_up; > }; > > -/* Clean up on domain destruction */ > -void vm_event_cleanup(struct domain *d); > - > /* Returns whether a ring has been set up */ > bool vm_event_check_ring(struct vm_event_domain *ved); > > @@ -88,7 +85,18 @@ void vm_event_cancel_slot(struct domain *d, struct vm_event_domain *ved); > void vm_event_put_request(struct domain *d, struct vm_event_domain *ved, > vm_event_request_t *req); > > +#ifdef CONFIG_MEM_ACCESS > +/* Clean up on domain destruction */ > +void vm_event_cleanup(struct domain *d); > int vm_event_domctl(struct domain *d, struct xen_domctl_vm_event_op *vec); > +#else > +static inline void vm_event_cleanup(struct domain *d) {} > +static inline int vm_event_domctl(struct domain *d, > + struct xen_domctl_vm_event_op *vec) > +{ > + return -EINVAL; > +} > +#endif > > void vm_event_vcpu_pause(struct vcpu *v); > void vm_event_vcpu_unpause(struct vcpu *v); > -- > 2.25.1 >
On 02/01/2025 19:34, Stefano Stabellini wrote: > CAUTION: This message has originated from an External Source. Please use proper judgment and caution when opening attachments, clicking links, or responding to this email. > > > On Mon, 30 Dec 2024, Sergiy Kibrik wrote: >> From: Stefano Stabellini <stefano.stabellini@amd.com> >> >> Extend coverage of CONFIG_MEM_ACCESS option and make the build of VM events >> and monitoring support optional. >> This is to reduce code size on Arm when this option isn't enabled. >> >> Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com> >> Signed-off-by: Sergiy Kibrik <Sergiy_Kibrik@epam.com> Reviewed-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com> - Ayan
On 30.12.2024 07:30, Sergiy Kibrik wrote: > From: Stefano Stabellini <stefano.stabellini@amd.com> > > Extend coverage of CONFIG_MEM_ACCESS option and make the build of VM events > and monitoring support optional. Yet doesn't this end up in things becoming misleading? Don't we rather need a 2nd Kconfig option, with a dependency between the two? Or alternatively a rename of the existing option (to describe the higher-level feature rather than the lower level one)? Tamas, I'm particularly interested in knowing your view here as well. Jan > This is to reduce code size on Arm when this option isn't enabled. > > Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com> > Signed-off-by: Sergiy Kibrik <Sergiy_Kibrik@epam.com> > --- > xen/arch/arm/Makefile | 4 ++-- > xen/arch/arm/vsmc.c | 3 ++- > xen/common/Makefile | 4 ++-- > xen/include/xen/monitor.h | 9 +++++++++ > xen/include/xen/vm_event.h | 14 +++++++++++--- > 5 files changed, 26 insertions(+), 8 deletions(-) > > diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile > index 43ab5e8f25..8903eb0bf2 100644 > --- a/xen/arch/arm/Makefile > +++ b/xen/arch/arm/Makefile > @@ -39,7 +39,7 @@ obj-$(CONFIG_LIVEPATCH) += livepatch.o > obj-$(CONFIG_LLC_COLORING) += llc-coloring.o > obj-$(CONFIG_MEM_ACCESS) += mem_access.o > obj-y += mm.o > -obj-y += monitor.o > +obj-$(CONFIG_MEM_ACCESS) += monitor.o > obj-y += p2m.o > obj-y += platform.o > obj-y += platform_hypercall.o > @@ -65,7 +65,7 @@ obj-$(CONFIG_VGICV2) += vgic-v2.o > obj-$(CONFIG_GICV3) += vgic-v3.o > obj-$(CONFIG_HAS_ITS) += vgic-v3-its.o > endif > -obj-y += vm_event.o > +obj-$(CONFIG_MEM_ACCESS) += vm_event.o > obj-y += vtimer.o > obj-$(CONFIG_SBSA_VUART_CONSOLE) += vpl011.o > obj-y += vsmc.o > diff --git a/xen/arch/arm/vsmc.c b/xen/arch/arm/vsmc.c > index 62d8117a12..1c13326bdf 100644 > --- a/xen/arch/arm/vsmc.c > +++ b/xen/arch/arm/vsmc.c > @@ -330,7 +330,8 @@ void do_trap_smc(struct cpu_user_regs *regs, const union hsr hsr) > } > > /* If monitor is enabled, let it handle the call. */ > - if ( current->domain->arch.monitor.privileged_call_enabled ) > + if ( IS_ENABLED(CONFIG_MEM_ACCESS) && > + current->domain->arch.monitor.privileged_call_enabled ) > rc = monitor_smc(); > > if ( rc == 1 ) > diff --git a/xen/common/Makefile b/xen/common/Makefile > index cba3b32733..e3c6a857ab 100644 > --- a/xen/common/Makefile > +++ b/xen/common/Makefile > @@ -54,7 +54,7 @@ obj-y += timer.o > obj-$(CONFIG_TRACEBUFFER) += trace.o > obj-y += version.o > obj-y += virtual_region.o > -obj-y += vm_event.o > +obj-$(CONFIG_MEM_ACCESS) += vm_event.o > obj-$(CONFIG_HAS_VMAP) += vmap.o > obj-y += vsprintf.o > obj-y += wait.o > @@ -68,7 +68,7 @@ obj-$(CONFIG_COMPAT) += $(addprefix compat/,domain.o memory.o multicall.o xlat.o > > ifneq ($(CONFIG_PV_SHIM_EXCLUSIVE),y) > obj-y += domctl.o > -obj-y += monitor.o > +obj-$(CONFIG_MEM_ACCESS) += monitor.o > obj-y += sysctl.o > endif > > diff --git a/xen/include/xen/monitor.h b/xen/include/xen/monitor.h > index 713d54f7c1..f1359abb94 100644 > --- a/xen/include/xen/monitor.h > +++ b/xen/include/xen/monitor.h > @@ -27,8 +27,17 @@ > struct domain; > struct xen_domctl_monitor_op; > > +#ifdef CONFIG_MEM_ACCESS > int monitor_domctl(struct domain *d, struct xen_domctl_monitor_op *mop); > void monitor_guest_request(void); > +#else > +static inline int monitor_domctl(struct domain *d, > + struct xen_domctl_monitor_op *mop) > +{ > + return -EINVAL; > +} > +static inline void monitor_guest_request(void) {} > +#endif > > int monitor_traps(struct vcpu *v, bool sync, vm_event_request_t *req); > > diff --git a/xen/include/xen/vm_event.h b/xen/include/xen/vm_event.h > index 9a86358b42..72e720e378 100644 > --- a/xen/include/xen/vm_event.h > +++ b/xen/include/xen/vm_event.h > @@ -50,9 +50,6 @@ struct vm_event_domain > unsigned int last_vcpu_wake_up; > }; > > -/* Clean up on domain destruction */ > -void vm_event_cleanup(struct domain *d); > - > /* Returns whether a ring has been set up */ > bool vm_event_check_ring(struct vm_event_domain *ved); > > @@ -88,7 +85,18 @@ void vm_event_cancel_slot(struct domain *d, struct vm_event_domain *ved); > void vm_event_put_request(struct domain *d, struct vm_event_domain *ved, > vm_event_request_t *req); > > +#ifdef CONFIG_MEM_ACCESS > +/* Clean up on domain destruction */ > +void vm_event_cleanup(struct domain *d); > int vm_event_domctl(struct domain *d, struct xen_domctl_vm_event_op *vec); > +#else > +static inline void vm_event_cleanup(struct domain *d) {} > +static inline int vm_event_domctl(struct domain *d, > + struct xen_domctl_vm_event_op *vec) > +{ > + return -EINVAL; > +} > +#endif > > void vm_event_vcpu_pause(struct vcpu *v); > void vm_event_vcpu_unpause(struct vcpu *v);
On Mon, Jan 6, 2025 at 5:16 AM Jan Beulich <jbeulich@suse.com> wrote: > > On 30.12.2024 07:30, Sergiy Kibrik wrote: > > From: Stefano Stabellini <stefano.stabellini@amd.com> > > > > Extend coverage of CONFIG_MEM_ACCESS option and make the build of VM events > > and monitoring support optional. > > Yet doesn't this end up in things becoming misleading? Don't we rather need a > 2nd Kconfig option, with a dependency between the two? Or alternatively a > rename of the existing option (to describe the higher-level feature rather > than the lower level one)? Tamas, I'm particularly interested in knowing your > view here as well. Thanks Jan, I was thinking the same thing. The dependency of these subsystems is mem_access -> monitor -> vm_event. If the goal here is to disable all three levels the ideal way would be to have separate kconfig options for each level. It may be a bit too fine-grained though on ARM since there are only two types of events for monitor (SMC & mem_access) and only the monitor uses the vm_event channel (no mem-sharing/paging on ARM). So if doing separate kconfig for each individual feature is an overkill I would suggest using CONFIG_VM_EVENT that disables all three levels, including both mem_access & smc monitor hooks. Tamas
On 06.01.2025 15:05, Tamas K Lengyel wrote: > On Mon, Jan 6, 2025 at 5:16 AM Jan Beulich <jbeulich@suse.com> wrote: >> >> On 30.12.2024 07:30, Sergiy Kibrik wrote: >>> From: Stefano Stabellini <stefano.stabellini@amd.com> >>> >>> Extend coverage of CONFIG_MEM_ACCESS option and make the build of VM events >>> and monitoring support optional. >> >> Yet doesn't this end up in things becoming misleading? Don't we rather need a >> 2nd Kconfig option, with a dependency between the two? Or alternatively a >> rename of the existing option (to describe the higher-level feature rather >> than the lower level one)? Tamas, I'm particularly interested in knowing your >> view here as well. > > Thanks Jan, I was thinking the same thing. The dependency of these > subsystems is mem_access -> monitor -> vm_event. If the goal here is > to disable all three levels the ideal way would be to have separate > kconfig options for each level. It may be a bit too fine-grained > though on ARM since there are only two types of events for monitor > (SMC & mem_access) and only the monitor uses the vm_event channel (no > mem-sharing/paging on ARM). So if doing separate kconfig for each > individual feature is an overkill I would suggest using > CONFIG_VM_EVENT that disables all three levels, including both > mem_access & smc monitor hooks. Except that "disables all three levels" doesn't work, unless the other option(s) are promptless (and selected). I'd have expected VM_EVENT to maybe have a "depends on MEM_ACCESS", whereas a "select MEM_ACCESS" wouldn't make much sense as long as MEM_ACCESS can be enabled individually (with it being unclear to me whether such a configuration is actually useful in any way). Jan
On Mon, Jan 6, 2025 at 10:10 AM Jan Beulich <jbeulich@suse.com> wrote: > > On 06.01.2025 15:05, Tamas K Lengyel wrote: > > On Mon, Jan 6, 2025 at 5:16 AM Jan Beulich <jbeulich@suse.com> wrote: > >> > >> On 30.12.2024 07:30, Sergiy Kibrik wrote: > >>> From: Stefano Stabellini <stefano.stabellini@amd.com> > >>> > >>> Extend coverage of CONFIG_MEM_ACCESS option and make the build of VM events > >>> and monitoring support optional. > >> > >> Yet doesn't this end up in things becoming misleading? Don't we rather need a > >> 2nd Kconfig option, with a dependency between the two? Or alternatively a > >> rename of the existing option (to describe the higher-level feature rather > >> than the lower level one)? Tamas, I'm particularly interested in knowing your > >> view here as well. > > > > Thanks Jan, I was thinking the same thing. The dependency of these > > subsystems is mem_access -> monitor -> vm_event. If the goal here is > > to disable all three levels the ideal way would be to have separate > > kconfig options for each level. It may be a bit too fine-grained > > though on ARM since there are only two types of events for monitor > > (SMC & mem_access) and only the monitor uses the vm_event channel (no > > mem-sharing/paging on ARM). So if doing separate kconfig for each > > individual feature is an overkill I would suggest using > > CONFIG_VM_EVENT that disables all three levels, including both > > mem_access & smc monitor hooks. > > Except that "disables all three levels" doesn't work, unless the other > option(s) are promptless (and selected). I'd have expected VM_EVENT to > maybe have a "depends on MEM_ACCESS", whereas a "select MEM_ACCESS" > wouldn't make much sense as long as MEM_ACCESS can be enabled > individually (with it being unclear to me whether such a configuration > is actually useful in any way). Not sure I follow. None of these systems make sense to enable individually. Without vm_event monitor/mem_access are useless, that's why I would pick CONFIG_VM_EVENT as the option on ARM to disable all three levels if we don't want to start splitting it into multiple kconfig options (which I think may be an overkill here). Tamas
diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile index 43ab5e8f25..8903eb0bf2 100644 --- a/xen/arch/arm/Makefile +++ b/xen/arch/arm/Makefile @@ -39,7 +39,7 @@ obj-$(CONFIG_LIVEPATCH) += livepatch.o obj-$(CONFIG_LLC_COLORING) += llc-coloring.o obj-$(CONFIG_MEM_ACCESS) += mem_access.o obj-y += mm.o -obj-y += monitor.o +obj-$(CONFIG_MEM_ACCESS) += monitor.o obj-y += p2m.o obj-y += platform.o obj-y += platform_hypercall.o @@ -65,7 +65,7 @@ obj-$(CONFIG_VGICV2) += vgic-v2.o obj-$(CONFIG_GICV3) += vgic-v3.o obj-$(CONFIG_HAS_ITS) += vgic-v3-its.o endif -obj-y += vm_event.o +obj-$(CONFIG_MEM_ACCESS) += vm_event.o obj-y += vtimer.o obj-$(CONFIG_SBSA_VUART_CONSOLE) += vpl011.o obj-y += vsmc.o diff --git a/xen/arch/arm/vsmc.c b/xen/arch/arm/vsmc.c index 62d8117a12..1c13326bdf 100644 --- a/xen/arch/arm/vsmc.c +++ b/xen/arch/arm/vsmc.c @@ -330,7 +330,8 @@ void do_trap_smc(struct cpu_user_regs *regs, const union hsr hsr) } /* If monitor is enabled, let it handle the call. */ - if ( current->domain->arch.monitor.privileged_call_enabled ) + if ( IS_ENABLED(CONFIG_MEM_ACCESS) && + current->domain->arch.monitor.privileged_call_enabled ) rc = monitor_smc(); if ( rc == 1 ) diff --git a/xen/common/Makefile b/xen/common/Makefile index cba3b32733..e3c6a857ab 100644 --- a/xen/common/Makefile +++ b/xen/common/Makefile @@ -54,7 +54,7 @@ obj-y += timer.o obj-$(CONFIG_TRACEBUFFER) += trace.o obj-y += version.o obj-y += virtual_region.o -obj-y += vm_event.o +obj-$(CONFIG_MEM_ACCESS) += vm_event.o obj-$(CONFIG_HAS_VMAP) += vmap.o obj-y += vsprintf.o obj-y += wait.o @@ -68,7 +68,7 @@ obj-$(CONFIG_COMPAT) += $(addprefix compat/,domain.o memory.o multicall.o xlat.o ifneq ($(CONFIG_PV_SHIM_EXCLUSIVE),y) obj-y += domctl.o -obj-y += monitor.o +obj-$(CONFIG_MEM_ACCESS) += monitor.o obj-y += sysctl.o endif diff --git a/xen/include/xen/monitor.h b/xen/include/xen/monitor.h index 713d54f7c1..f1359abb94 100644 --- a/xen/include/xen/monitor.h +++ b/xen/include/xen/monitor.h @@ -27,8 +27,17 @@ struct domain; struct xen_domctl_monitor_op; +#ifdef CONFIG_MEM_ACCESS int monitor_domctl(struct domain *d, struct xen_domctl_monitor_op *mop); void monitor_guest_request(void); +#else +static inline int monitor_domctl(struct domain *d, + struct xen_domctl_monitor_op *mop) +{ + return -EINVAL; +} +static inline void monitor_guest_request(void) {} +#endif int monitor_traps(struct vcpu *v, bool sync, vm_event_request_t *req); diff --git a/xen/include/xen/vm_event.h b/xen/include/xen/vm_event.h index 9a86358b42..72e720e378 100644 --- a/xen/include/xen/vm_event.h +++ b/xen/include/xen/vm_event.h @@ -50,9 +50,6 @@ struct vm_event_domain unsigned int last_vcpu_wake_up; }; -/* Clean up on domain destruction */ -void vm_event_cleanup(struct domain *d); - /* Returns whether a ring has been set up */ bool vm_event_check_ring(struct vm_event_domain *ved); @@ -88,7 +85,18 @@ void vm_event_cancel_slot(struct domain *d, struct vm_event_domain *ved); void vm_event_put_request(struct domain *d, struct vm_event_domain *ved, vm_event_request_t *req); +#ifdef CONFIG_MEM_ACCESS +/* Clean up on domain destruction */ +void vm_event_cleanup(struct domain *d); int vm_event_domctl(struct domain *d, struct xen_domctl_vm_event_op *vec); +#else +static inline void vm_event_cleanup(struct domain *d) {} +static inline int vm_event_domctl(struct domain *d, + struct xen_domctl_vm_event_op *vec) +{ + return -EINVAL; +} +#endif void vm_event_vcpu_pause(struct vcpu *v); void vm_event_vcpu_unpause(struct vcpu *v);