| Message ID | 20171012104141.26902-18-christoffer.dall@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Oct 12, 2017 at 12:41:21PM +0200, Christoffer Dall wrote: > There's a semantic difference between the EL1 registers that control > operation of a kernel running in EL1 and EL1 registers that only control > userspace execution in EL0. Since we can defer saving/restoring the > latter, move them into their own function. > > We also take this chance to rename the function saving/restoring the > remaining system register to make it clear this function deals with > the EL1 system registers. > > No functional change. > > Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> > --- > arch/arm64/kvm/hyp/sysreg-sr.c | 34 +++++++++++++++++++++++----------- > 1 file changed, 23 insertions(+), 11 deletions(-) > > diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c > index c4a3714..193c2b0 100644 > --- a/arch/arm64/kvm/hyp/sysreg-sr.c > +++ b/arch/arm64/kvm/hyp/sysreg-sr.c > @@ -34,14 +34,18 @@ static void __hyp_text __sysreg_do_nothing(struct kvm_cpu_context *ctxt) { } > > static void __hyp_text __sysreg_save_common_state(struct kvm_cpu_context *ctxt) > { > + ctxt->sys_regs[MDSCR_EL1] = read_sysreg(mdscr_el1); > + ctxt->gp_regs.regs.sp = read_sysreg(sp_el0); Maybe a comment stating that sp_el0 is here, instead of down in user state, because arm64 Linux chooses to use it for the 'current' pointer. At least that's why I think it's been promoted to common state, but maybe there was a different reason I missed. > +} > + > +static void __hyp_text __sysreg_save_user_state(struct kvm_cpu_context *ctxt) > +{ > ctxt->sys_regs[ACTLR_EL1] = read_sysreg(actlr_el1); > ctxt->sys_regs[TPIDR_EL0] = read_sysreg(tpidr_el0); > ctxt->sys_regs[TPIDRRO_EL0] = read_sysreg(tpidrro_el0); > - ctxt->sys_regs[MDSCR_EL1] = read_sysreg(mdscr_el1); > - ctxt->gp_regs.regs.sp = read_sysreg(sp_el0); > } > > -static void __hyp_text __sysreg_save_state(struct kvm_cpu_context *ctxt) > +static void __hyp_text __sysreg_save_el1_state(struct kvm_cpu_context *ctxt) > { > ctxt->sys_regs[MPIDR_EL1] = read_sysreg(vmpidr_el2); > ctxt->sys_regs[CSSELR_EL1] = read_sysreg(csselr_el1); > @@ -70,31 +74,37 @@ static void __hyp_text __sysreg_save_state(struct kvm_cpu_context *ctxt) > } > > static hyp_alternate_select(__sysreg_call_save_host_state, > - __sysreg_save_state, __sysreg_do_nothing, > + __sysreg_save_el1_state, __sysreg_do_nothing, > ARM64_HAS_VIRT_HOST_EXTN); > > void __hyp_text __sysreg_save_host_state(struct kvm_cpu_context *ctxt) > { > __sysreg_call_save_host_state()(ctxt); > __sysreg_save_common_state(ctxt); > + __sysreg_save_user_state(ctxt); > } > > void __hyp_text __sysreg_save_guest_state(struct kvm_cpu_context *ctxt) > { > - __sysreg_save_state(ctxt); > + __sysreg_save_el1_state(ctxt); > __sysreg_save_common_state(ctxt); > + __sysreg_save_user_state(ctxt); > } > > static void __hyp_text __sysreg_restore_common_state(struct kvm_cpu_context *ctxt) > { > - write_sysreg(ctxt->sys_regs[ACTLR_EL1], actlr_el1); > - write_sysreg(ctxt->sys_regs[TPIDR_EL0], tpidr_el0); > - write_sysreg(ctxt->sys_regs[TPIDRRO_EL0], tpidrro_el0); > write_sysreg(ctxt->sys_regs[MDSCR_EL1], mdscr_el1); > write_sysreg(ctxt->gp_regs.regs.sp, sp_el0); > } > > -static void __hyp_text __sysreg_restore_state(struct kvm_cpu_context *ctxt) > +static void __hyp_text __sysreg_restore_user_state(struct kvm_cpu_context *ctxt) > +{ > + write_sysreg(ctxt->sys_regs[ACTLR_EL1], actlr_el1); > + write_sysreg(ctxt->sys_regs[TPIDR_EL0], tpidr_el0); > + write_sysreg(ctxt->sys_regs[TPIDRRO_EL0], tpidrro_el0); > +} > + > +static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt) > { > write_sysreg(ctxt->sys_regs[MPIDR_EL1], vmpidr_el2); > write_sysreg(ctxt->sys_regs[CSSELR_EL1], csselr_el1); > @@ -123,19 +133,21 @@ static void __hyp_text __sysreg_restore_state(struct kvm_cpu_context *ctxt) > } > > static hyp_alternate_select(__sysreg_call_restore_host_state, > - __sysreg_restore_state, __sysreg_do_nothing, > + __sysreg_restore_el1_state, __sysreg_do_nothing, > ARM64_HAS_VIRT_HOST_EXTN); > > void __hyp_text __sysreg_restore_host_state(struct kvm_cpu_context *ctxt) > { > __sysreg_call_restore_host_state()(ctxt); > __sysreg_restore_common_state(ctxt); > + __sysreg_restore_user_state(ctxt); > } > > void __hyp_text __sysreg_restore_guest_state(struct kvm_cpu_context *ctxt) > { > - __sysreg_restore_state(ctxt); > + __sysreg_restore_el1_state(ctxt); > __sysreg_restore_common_state(ctxt); > + __sysreg_restore_user_state(ctxt); > } > > static void __hyp_text __fpsimd32_save_state(struct kvm_cpu_context *ctxt) > -- > 2.9.0 > Otherwise Reviewed-by: Andrew Jones <drjones@redhat.com>
On Wed, Nov 08, 2017 at 10:32:30AM +0100, Andrew Jones wrote: > On Thu, Oct 12, 2017 at 12:41:21PM +0200, Christoffer Dall wrote: > > There's a semantic difference between the EL1 registers that control > > operation of a kernel running in EL1 and EL1 registers that only control > > userspace execution in EL0. Since we can defer saving/restoring the > > latter, move them into their own function. > > > > We also take this chance to rename the function saving/restoring the > > remaining system register to make it clear this function deals with > > the EL1 system registers. > > > > No functional change. > > > > Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> > > --- > > arch/arm64/kvm/hyp/sysreg-sr.c | 34 +++++++++++++++++++++++----------- > > 1 file changed, 23 insertions(+), 11 deletions(-) > > > > diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c > > index c4a3714..193c2b0 100644 > > --- a/arch/arm64/kvm/hyp/sysreg-sr.c > > +++ b/arch/arm64/kvm/hyp/sysreg-sr.c > > @@ -34,14 +34,18 @@ static void __hyp_text __sysreg_do_nothing(struct kvm_cpu_context *ctxt) { } > > > > static void __hyp_text __sysreg_save_common_state(struct kvm_cpu_context *ctxt) > > { > > + ctxt->sys_regs[MDSCR_EL1] = read_sysreg(mdscr_el1); > > + ctxt->gp_regs.regs.sp = read_sysreg(sp_el0); > > Maybe a comment stating that sp_el0 is here, instead of down in user > state, because arm64 Linux chooses to use it for the 'current' pointer. > At least that's why I think it's been promoted to common state, but maybe > there was a different reason I missed. > That is the reason. I can add a comment. > > +} > > + > > +static void __hyp_text __sysreg_save_user_state(struct kvm_cpu_context *ctxt) > > +{ > > ctxt->sys_regs[ACTLR_EL1] = read_sysreg(actlr_el1); > > ctxt->sys_regs[TPIDR_EL0] = read_sysreg(tpidr_el0); > > ctxt->sys_regs[TPIDRRO_EL0] = read_sysreg(tpidrro_el0); > > - ctxt->sys_regs[MDSCR_EL1] = read_sysreg(mdscr_el1); > > - ctxt->gp_regs.regs.sp = read_sysreg(sp_el0); > > } > > > > -static void __hyp_text __sysreg_save_state(struct kvm_cpu_context *ctxt) > > +static void __hyp_text __sysreg_save_el1_state(struct kvm_cpu_context *ctxt) > > { > > ctxt->sys_regs[MPIDR_EL1] = read_sysreg(vmpidr_el2); > > ctxt->sys_regs[CSSELR_EL1] = read_sysreg(csselr_el1); > > @@ -70,31 +74,37 @@ static void __hyp_text __sysreg_save_state(struct kvm_cpu_context *ctxt) > > } > > > > static hyp_alternate_select(__sysreg_call_save_host_state, > > - __sysreg_save_state, __sysreg_do_nothing, > > + __sysreg_save_el1_state, __sysreg_do_nothing, > > ARM64_HAS_VIRT_HOST_EXTN); > > > > void __hyp_text __sysreg_save_host_state(struct kvm_cpu_context *ctxt) > > { > > __sysreg_call_save_host_state()(ctxt); > > __sysreg_save_common_state(ctxt); > > + __sysreg_save_user_state(ctxt); > > } > > > > void __hyp_text __sysreg_save_guest_state(struct kvm_cpu_context *ctxt) > > { > > - __sysreg_save_state(ctxt); > > + __sysreg_save_el1_state(ctxt); > > __sysreg_save_common_state(ctxt); > > + __sysreg_save_user_state(ctxt); > > } > > > > static void __hyp_text __sysreg_restore_common_state(struct kvm_cpu_context *ctxt) > > { > > - write_sysreg(ctxt->sys_regs[ACTLR_EL1], actlr_el1); > > - write_sysreg(ctxt->sys_regs[TPIDR_EL0], tpidr_el0); > > - write_sysreg(ctxt->sys_regs[TPIDRRO_EL0], tpidrro_el0); > > write_sysreg(ctxt->sys_regs[MDSCR_EL1], mdscr_el1); > > write_sysreg(ctxt->gp_regs.regs.sp, sp_el0); > > } > > > > -static void __hyp_text __sysreg_restore_state(struct kvm_cpu_context *ctxt) > > +static void __hyp_text __sysreg_restore_user_state(struct kvm_cpu_context *ctxt) > > +{ > > + write_sysreg(ctxt->sys_regs[ACTLR_EL1], actlr_el1); > > + write_sysreg(ctxt->sys_regs[TPIDR_EL0], tpidr_el0); > > + write_sysreg(ctxt->sys_regs[TPIDRRO_EL0], tpidrro_el0); > > +} > > + > > +static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt) > > { > > write_sysreg(ctxt->sys_regs[MPIDR_EL1], vmpidr_el2); > > write_sysreg(ctxt->sys_regs[CSSELR_EL1], csselr_el1); > > @@ -123,19 +133,21 @@ static void __hyp_text __sysreg_restore_state(struct kvm_cpu_context *ctxt) > > } > > > > static hyp_alternate_select(__sysreg_call_restore_host_state, > > - __sysreg_restore_state, __sysreg_do_nothing, > > + __sysreg_restore_el1_state, __sysreg_do_nothing, > > ARM64_HAS_VIRT_HOST_EXTN); > > > > void __hyp_text __sysreg_restore_host_state(struct kvm_cpu_context *ctxt) > > { > > __sysreg_call_restore_host_state()(ctxt); > > __sysreg_restore_common_state(ctxt); > > + __sysreg_restore_user_state(ctxt); > > } > > > > void __hyp_text __sysreg_restore_guest_state(struct kvm_cpu_context *ctxt) > > { > > - __sysreg_restore_state(ctxt); > > + __sysreg_restore_el1_state(ctxt); > > __sysreg_restore_common_state(ctxt); > > + __sysreg_restore_user_state(ctxt); > > } > > > > static void __hyp_text __fpsimd32_save_state(struct kvm_cpu_context *ctxt) > > -- > > 2.9.0 > > > > Otherwise > > Reviewed-by: Andrew Jones <drjones@redhat.com> Thanks, -Christoffer
diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c index c4a3714..193c2b0 100644 --- a/arch/arm64/kvm/hyp/sysreg-sr.c +++ b/arch/arm64/kvm/hyp/sysreg-sr.c @@ -34,14 +34,18 @@ static void __hyp_text __sysreg_do_nothing(struct kvm_cpu_context *ctxt) { } static void __hyp_text __sysreg_save_common_state(struct kvm_cpu_context *ctxt) { + ctxt->sys_regs[MDSCR_EL1] = read_sysreg(mdscr_el1); + ctxt->gp_regs.regs.sp = read_sysreg(sp_el0); +} + +static void __hyp_text __sysreg_save_user_state(struct kvm_cpu_context *ctxt) +{ ctxt->sys_regs[ACTLR_EL1] = read_sysreg(actlr_el1); ctxt->sys_regs[TPIDR_EL0] = read_sysreg(tpidr_el0); ctxt->sys_regs[TPIDRRO_EL0] = read_sysreg(tpidrro_el0); - ctxt->sys_regs[MDSCR_EL1] = read_sysreg(mdscr_el1); - ctxt->gp_regs.regs.sp = read_sysreg(sp_el0); } -static void __hyp_text __sysreg_save_state(struct kvm_cpu_context *ctxt) +static void __hyp_text __sysreg_save_el1_state(struct kvm_cpu_context *ctxt) { ctxt->sys_regs[MPIDR_EL1] = read_sysreg(vmpidr_el2); ctxt->sys_regs[CSSELR_EL1] = read_sysreg(csselr_el1); @@ -70,31 +74,37 @@ static void __hyp_text __sysreg_save_state(struct kvm_cpu_context *ctxt) } static hyp_alternate_select(__sysreg_call_save_host_state, - __sysreg_save_state, __sysreg_do_nothing, + __sysreg_save_el1_state, __sysreg_do_nothing, ARM64_HAS_VIRT_HOST_EXTN); void __hyp_text __sysreg_save_host_state(struct kvm_cpu_context *ctxt) { __sysreg_call_save_host_state()(ctxt); __sysreg_save_common_state(ctxt); + __sysreg_save_user_state(ctxt); } void __hyp_text __sysreg_save_guest_state(struct kvm_cpu_context *ctxt) { - __sysreg_save_state(ctxt); + __sysreg_save_el1_state(ctxt); __sysreg_save_common_state(ctxt); + __sysreg_save_user_state(ctxt); } static void __hyp_text __sysreg_restore_common_state(struct kvm_cpu_context *ctxt) { - write_sysreg(ctxt->sys_regs[ACTLR_EL1], actlr_el1); - write_sysreg(ctxt->sys_regs[TPIDR_EL0], tpidr_el0); - write_sysreg(ctxt->sys_regs[TPIDRRO_EL0], tpidrro_el0); write_sysreg(ctxt->sys_regs[MDSCR_EL1], mdscr_el1); write_sysreg(ctxt->gp_regs.regs.sp, sp_el0); } -static void __hyp_text __sysreg_restore_state(struct kvm_cpu_context *ctxt) +static void __hyp_text __sysreg_restore_user_state(struct kvm_cpu_context *ctxt) +{ + write_sysreg(ctxt->sys_regs[ACTLR_EL1], actlr_el1); + write_sysreg(ctxt->sys_regs[TPIDR_EL0], tpidr_el0); + write_sysreg(ctxt->sys_regs[TPIDRRO_EL0], tpidrro_el0); +} + +static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt) { write_sysreg(ctxt->sys_regs[MPIDR_EL1], vmpidr_el2); write_sysreg(ctxt->sys_regs[CSSELR_EL1], csselr_el1); @@ -123,19 +133,21 @@ static void __hyp_text __sysreg_restore_state(struct kvm_cpu_context *ctxt) } static hyp_alternate_select(__sysreg_call_restore_host_state, - __sysreg_restore_state, __sysreg_do_nothing, + __sysreg_restore_el1_state, __sysreg_do_nothing, ARM64_HAS_VIRT_HOST_EXTN); void __hyp_text __sysreg_restore_host_state(struct kvm_cpu_context *ctxt) { __sysreg_call_restore_host_state()(ctxt); __sysreg_restore_common_state(ctxt); + __sysreg_restore_user_state(ctxt); } void __hyp_text __sysreg_restore_guest_state(struct kvm_cpu_context *ctxt) { - __sysreg_restore_state(ctxt); + __sysreg_restore_el1_state(ctxt); __sysreg_restore_common_state(ctxt); + __sysreg_restore_user_state(ctxt); } static void __hyp_text __fpsimd32_save_state(struct kvm_cpu_context *ctxt)
There's a semantic difference between the EL1 registers that control operation of a kernel running in EL1 and EL1 registers that only control userspace execution in EL0. Since we can defer saving/restoring the latter, move them into their own function. We also take this chance to rename the function saving/restoring the remaining system register to make it clear this function deals with the EL1 system registers. No functional change. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> --- arch/arm64/kvm/hyp/sysreg-sr.c | 34 +++++++++++++++++++++++----------- 1 file changed, 23 insertions(+), 11 deletions(-)