Now that we are explicitly telling the host FP code which register state it needs to save we can remove the manipulation of TIF_SVE from the KVM code, simplifying it and allowing us to optimise our handling of normal tasks. Remove the manipulation of TIF_SVE from KVM and instead rely on to_save to ensure we save the correct data for it.
Signed-off-by: Mark Brown <[email protected]> --- arch/arm64/kernel/fpsimd.c | 22 ++++------------------ arch/arm64/kvm/fpsimd.c | 3 --- 2 files changed, 4 insertions(+), 21 deletions(-) diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 7be20ced2c45..aaea2dc02cbd 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -436,8 +436,8 @@ static void task_fpsimd_load(void) * last, if KVM is involved this may be the guest VM context rather * than the host thread for the VM pointed to by current. This means * that we must always reference the state storage via last rather - * than via current, other than the TIF_ flags which KVM will - * carefully maintain for us. + * than via current, if we are saving KVM state then it will have + * ensured that the type of registers to save is set in last->to_save. */ static void fpsimd_save(void) { @@ -454,27 +454,13 @@ static void fpsimd_save(void) if (test_thread_flag(TIF_FOREIGN_FPSTATE)) return; - if (test_thread_flag(TIF_SVE)) { + if ((last->to_save == FP_STATE_TASK && test_thread_flag(TIF_SVE)) || + last->to_save == FP_STATE_SVE) { save_sve_regs = true; save_ffr = true; vl = last->sve_vl; } - /* - * For now we're just validating that the requested state is - * consistent with what we'd otherwise work out. - */ - switch (last->to_save) { - case FP_STATE_TASK: - break; - case FP_STATE_FPSIMD: - WARN_ON_ONCE(save_sve_regs); - break; - case FP_STATE_SVE: - WARN_ON_ONCE(!save_sve_regs); - break; - } - if (system_supports_sme()) { u64 *svcr = last->svcr; diff --git a/arch/arm64/kvm/fpsimd.c b/arch/arm64/kvm/fpsimd.c index db0b2bacaeb8..8a79823fce68 100644 --- a/arch/arm64/kvm/fpsimd.c +++ b/arch/arm64/kvm/fpsimd.c @@ -151,7 +151,6 @@ void kvm_arch_vcpu_ctxsync_fp(struct kvm_vcpu *vcpu) &vcpu->arch.fp_type, fp_type); clear_thread_flag(TIF_FOREIGN_FPSTATE); - update_thread_flag(TIF_SVE, vcpu_has_sve(vcpu)); } } @@ -208,7 +207,5 @@ void kvm_arch_vcpu_put_fp(struct kvm_vcpu *vcpu) sysreg_clear_set(CPACR_EL1, CPACR_EL1_ZEN_EL0EN, 0); } - update_thread_flag(TIF_SVE, 0); - local_irq_restore(flags); } -- 2.30.2 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
