Doing arithmetic on the vcpu pointer can be avoided by using another register as a base. Saves a few instructions on the switch path. Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> --- arch/arm/kvm/interrupts_head.S | 32 ++++++++++++++------------------ 1 file changed, 14 insertions(+), 18 deletions(-) diff --git a/arch/arm/kvm/interrupts_head.S b/arch/arm/kvm/interrupts_head.S index 0e423be..d2442f9 100644 --- a/arch/arm/kvm/interrupts_head.S +++ b/arch/arm/kvm/interrupts_head.S @@ -264,11 +264,10 @@ vcpu .req r0 @ vcpu pointer always in r0 str r3, [vcpu, #CP15_OFFSET(c1_CPACR)] str r4, [vcpu, #CP15_OFFSET(c2_TTBCR)] str r5, [vcpu, #CP15_OFFSET(c3_DACR)] - add vcpu, vcpu, #CP15_OFFSET(c2_TTBR0) - strd r6, r7, [vcpu] - add vcpu, vcpu, #CP15_OFFSET(c2_TTBR1) - CP15_OFFSET(c2_TTBR0) - strd r8, r9, [vcpu] - sub vcpu, vcpu, #CP15_OFFSET(c2_TTBR1) + add r2, vcpu, #CP15_OFFSET(c2_TTBR0) + strd r6, r7, [r2] + add r2, vcpu, #CP15_OFFSET(c2_TTBR1) + strd r8, r9, [r2] str r10, [vcpu, #CP15_OFFSET(c10_PRRR)] str r11, [vcpu, #CP15_OFFSET(c10_NMRR)] str r12, [vcpu, #CP15_OFFSET(c0_CSSELR)] @@ -362,11 +361,10 @@ vcpu .req r0 @ vcpu pointer always in r0 ldr r3, [vcpu, #CP15_OFFSET(c1_CPACR)] ldr r4, [vcpu, #CP15_OFFSET(c2_TTBCR)] ldr r5, [vcpu, #CP15_OFFSET(c3_DACR)] - add vcpu, vcpu, #CP15_OFFSET(c2_TTBR0) - ldrd r6, r7, [vcpu] - add vcpu, vcpu, #CP15_OFFSET(c2_TTBR1) - CP15_OFFSET(c2_TTBR0) - ldrd r8, r9, [vcpu] - sub vcpu, vcpu, #CP15_OFFSET(c2_TTBR1) + add r12, vcpu, #CP15_OFFSET(c2_TTBR0) + ldrd r6, r7, [r12] + add r12, vcpu, #CP15_OFFSET(c2_TTBR1) + ldrd r8, r9, [r12] ldr r10, [vcpu, #CP15_OFFSET(c10_PRRR)] ldr r11, [vcpu, #CP15_OFFSET(c10_NMRR)] ldr r12, [vcpu, #CP15_OFFSET(c0_CSSELR)] @@ -479,7 +477,7 @@ vcpu .req r0 @ vcpu pointer always in r0 * for the host. * * Assumes vcpu pointer in vcpu reg - * Clobbers r2-r4 + * Clobbers r2-r5 */ .macro save_timer_state #ifdef CONFIG_KVM_ARM_TIMER @@ -496,9 +494,8 @@ vcpu .req r0 @ vcpu pointer always in r0 mrrc p15, 3, r2, r3, c14 @ CNTV_CVAL ldr r4, =VCPU_TIMER_CNTV_CVAL - add vcpu, vcpu, r4 - strd r2, r3, [vcpu] - sub vcpu, vcpu, r4 + add r5, vcpu, r4 + strd r2, r3, [r5] 1: #endif @@ -513,7 +510,7 @@ vcpu .req r0 @ vcpu pointer always in r0 * for the host. * * Assumes vcpu pointer in vcpu reg - * Clobbers r2-r4 + * Clobbers r2-r5 */ .macro restore_timer_state @ Disallow physical timer access for the guest @@ -534,9 +531,8 @@ vcpu .req r0 @ vcpu pointer always in r0 mcrr p15, 4, r2, r3, c14 @ CNTVOFF ldr r4, =VCPU_TIMER_CNTV_CVAL - add vcpu, vcpu, r4 - ldrd r2, r3, [vcpu] - sub vcpu, vcpu, r4 + add r5, vcpu, r4 + ldrd r2, r3, [r5] mcrr p15, 3, r2, r3, c14 @ CNTV_CVAL isb -- 1.8.1 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
