linux/arch/powerpc/include/asm/kvm_book3s_asm.h
Anton Blanchard 18ad51dd34 powerpc: Add VDSO version of getcpu
We have a request for a fast method of getting CPU and NUMA node IDs
from userspace. This patch implements a getcpu VDSO function,
similar to x86.

Ben suggested we use SPRG3 which is userspace readable. SPRG3 can be
modified by a KVM guest, so we save the SPRG3 value in the paca and
restore it when transitioning from the guest to the host.

I have a glibc patch that implements sched_getcpu on top of this.
Testing on a POWER7:

baseline: 538 cycles
vdso:      30 cycles

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-07-11 14:18:40 +10:00

135 lines
3.2 KiB
C

/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* Copyright SUSE Linux Products GmbH 2009
*
* Authors: Alexander Graf <agraf@suse.de>
*/
#ifndef __ASM_KVM_BOOK3S_ASM_H__
#define __ASM_KVM_BOOK3S_ASM_H__
#ifdef __ASSEMBLY__
#ifdef CONFIG_KVM_BOOK3S_HANDLER
#include <asm/kvm_asm.h>
.macro DO_KVM intno
.if (\intno == BOOK3S_INTERRUPT_SYSTEM_RESET) || \
(\intno == BOOK3S_INTERRUPT_MACHINE_CHECK) || \
(\intno == BOOK3S_INTERRUPT_DATA_STORAGE) || \
(\intno == BOOK3S_INTERRUPT_INST_STORAGE) || \
(\intno == BOOK3S_INTERRUPT_DATA_SEGMENT) || \
(\intno == BOOK3S_INTERRUPT_INST_SEGMENT) || \
(\intno == BOOK3S_INTERRUPT_EXTERNAL) || \
(\intno == BOOK3S_INTERRUPT_EXTERNAL_HV) || \
(\intno == BOOK3S_INTERRUPT_ALIGNMENT) || \
(\intno == BOOK3S_INTERRUPT_PROGRAM) || \
(\intno == BOOK3S_INTERRUPT_FP_UNAVAIL) || \
(\intno == BOOK3S_INTERRUPT_DECREMENTER) || \
(\intno == BOOK3S_INTERRUPT_SYSCALL) || \
(\intno == BOOK3S_INTERRUPT_TRACE) || \
(\intno == BOOK3S_INTERRUPT_PERFMON) || \
(\intno == BOOK3S_INTERRUPT_ALTIVEC) || \
(\intno == BOOK3S_INTERRUPT_VSX)
b kvmppc_trampoline_\intno
kvmppc_resume_\intno:
.endif
.endm
#else
.macro DO_KVM intno
.endm
#endif /* CONFIG_KVM_BOOK3S_HANDLER */
#else /*__ASSEMBLY__ */
/*
* This struct goes in the PACA on 64-bit processors. It is used
* to store host state that needs to be saved when we enter a guest
* and restored when we exit, but isn't specific to any particular
* guest or vcpu. It also has some scratch fields used by the guest
* exit code.
*/
struct kvmppc_host_state {
ulong host_r1;
ulong host_r2;
ulong host_msr;
ulong vmhandler;
ulong scratch0;
ulong scratch1;
ulong sprg3;
u8 in_guest;
u8 restore_hid5;
u8 napping;
#ifdef CONFIG_KVM_BOOK3S_64_HV
u8 hwthread_req;
u8 hwthread_state;
struct kvm_vcpu *kvm_vcpu;
struct kvmppc_vcore *kvm_vcore;
unsigned long xics_phys;
u64 dabr;
u64 host_mmcr[3];
u32 host_pmc[8];
u64 host_purr;
u64 host_spurr;
u64 host_dscr;
u64 dec_expires;
#endif
};
struct kvmppc_book3s_shadow_vcpu {
ulong gpr[14];
u32 cr;
u32 xer;
u32 fault_dsisr;
u32 last_inst;
ulong ctr;
ulong lr;
ulong pc;
ulong shadow_srr1;
ulong fault_dar;
#ifdef CONFIG_PPC_BOOK3S_32
u32 sr[16]; /* Guest SRs */
struct kvmppc_host_state hstate;
#endif
#ifdef CONFIG_PPC_BOOK3S_64
u8 slb_max; /* highest used guest slb entry */
struct {
u64 esid;
u64 vsid;
} slb[64]; /* guest SLB */
#endif
};
#endif /*__ASSEMBLY__ */
/* Values for kvm_state */
#define KVM_HWTHREAD_IN_KERNEL 0
#define KVM_HWTHREAD_IN_NAP 1
#define KVM_HWTHREAD_IN_KVM 2
#endif /* __ASM_KVM_BOOK3S_ASM_H__ */