diff options
Diffstat (limited to 'arch/powerpc/include')
-rw-r--r-- | arch/powerpc/include/asm/cputable.h | 5 | ||||
-rw-r--r-- | arch/powerpc/include/asm/kvm_ppc.h | 100 | ||||
-rw-r--r-- | arch/powerpc/include/asm/reg.h | 9 |
3 files changed, 106 insertions, 8 deletions
diff --git a/arch/powerpc/include/asm/cputable.h b/arch/powerpc/include/asm/cputable.h index a1ebcbc3931f..cf00ff0d121d 100644 --- a/arch/powerpc/include/asm/cputable.h +++ b/arch/powerpc/include/asm/cputable.h @@ -209,8 +209,9 @@ static inline void cpu_feature_keys_init(void) { } #define CPU_FTR_POWER9_DD2_1 LONG_ASM_CONST(0x0000080000000000) #define CPU_FTR_P9_TM_HV_ASSIST LONG_ASM_CONST(0x0000100000000000) #define CPU_FTR_P9_TM_XER_SO_BUG LONG_ASM_CONST(0x0000200000000000) -#define CPU_FTR_P9_TLBIE_BUG LONG_ASM_CONST(0x0000400000000000) +#define CPU_FTR_P9_TLBIE_STQ_BUG LONG_ASM_CONST(0x0000400000000000) #define CPU_FTR_P9_TIDR LONG_ASM_CONST(0x0000800000000000) +#define CPU_FTR_P9_TLBIE_ERAT_BUG LONG_ASM_CONST(0x0001000000000000) #ifndef __ASSEMBLY__ @@ -457,7 +458,7 @@ static inline void cpu_feature_keys_init(void) { } CPU_FTR_CFAR | CPU_FTR_HVMODE | CPU_FTR_VMX_COPY | \ CPU_FTR_DBELL | CPU_FTR_HAS_PPR | CPU_FTR_ARCH_207S | \ CPU_FTR_TM_COMP | CPU_FTR_ARCH_300 | CPU_FTR_PKEY | \ - CPU_FTR_P9_TLBIE_BUG | CPU_FTR_P9_TIDR) + CPU_FTR_P9_TLBIE_STQ_BUG | CPU_FTR_P9_TLBIE_ERAT_BUG | CPU_FTR_P9_TIDR) #define CPU_FTRS_POWER9_DD2_0 CPU_FTRS_POWER9 #define CPU_FTRS_POWER9_DD2_1 (CPU_FTRS_POWER9 | CPU_FTR_POWER9_DD2_1) #define CPU_FTRS_POWER9_DD2_2 (CPU_FTRS_POWER9 | CPU_FTR_POWER9_DD2_1 | \ diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 8e8514efb124..ee62776e5433 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -452,9 +452,100 @@ static inline u32 kvmppc_get_xics_latch(void) return xirr; } -static inline void kvmppc_set_host_ipi(int cpu, u8 host_ipi) +/* + * To avoid the need to unnecessarily exit fully to the host kernel, an IPI to + * a CPU thread that's running/napping inside of a guest is by default regarded + * as a request to wake the CPU (if needed) and continue execution within the + * guest, potentially to process new state like externally-generated + * interrupts or IPIs sent from within the guest itself (e.g. H_PROD/H_IPI). + * + * To force an exit to the host kernel, kvmppc_set_host_ipi() must be called + * prior to issuing the IPI to set the corresponding 'host_ipi' flag in the + * target CPU's PACA. To avoid unnecessary exits to the host, this flag should + * be immediately cleared via kvmppc_clear_host_ipi() by the IPI handler on + * the receiving side prior to processing the IPI work. + * + * NOTE: + * + * We currently issue an smp_mb() at the beginning of kvmppc_set_host_ipi(). + * This is to guard against sequences such as the following: + * + * CPU + * X: smp_muxed_ipi_set_message(): + * X: smp_mb() + * X: message[RESCHEDULE] = 1 + * X: doorbell_global_ipi(42): + * X: kvmppc_set_host_ipi(42) + * X: ppc_msgsnd_sync()/smp_mb() + * X: ppc_msgsnd() -> 42 + * 42: doorbell_exception(): // from CPU X + * 42: ppc_msgsync() + * 105: smp_muxed_ipi_set_message(): + * 105: smb_mb() + * // STORE DEFERRED DUE TO RE-ORDERING + * --105: message[CALL_FUNCTION] = 1 + * | 105: doorbell_global_ipi(42): + * | 105: kvmppc_set_host_ipi(42) + * | 42: kvmppc_clear_host_ipi(42) + * | 42: smp_ipi_demux_relaxed() + * | 42: // returns to executing guest + * | // RE-ORDERED STORE COMPLETES + * ->105: message[CALL_FUNCTION] = 1 + * 105: ppc_msgsnd_sync()/smp_mb() + * 105: ppc_msgsnd() -> 42 + * 42: local_paca->kvm_hstate.host_ipi == 0 // IPI ignored + * 105: // hangs waiting on 42 to process messages/call_single_queue + * + * We also issue an smp_mb() at the end of kvmppc_clear_host_ipi(). This is + * to guard against sequences such as the following (as well as to create + * a read-side pairing with the barrier in kvmppc_set_host_ipi()): + * + * CPU + * X: smp_muxed_ipi_set_message(): + * X: smp_mb() + * X: message[RESCHEDULE] = 1 + * X: doorbell_global_ipi(42): + * X: kvmppc_set_host_ipi(42) + * X: ppc_msgsnd_sync()/smp_mb() + * X: ppc_msgsnd() -> 42 + * 42: doorbell_exception(): // from CPU X + * 42: ppc_msgsync() + * // STORE DEFERRED DUE TO RE-ORDERING + * -- 42: kvmppc_clear_host_ipi(42) + * | 42: smp_ipi_demux_relaxed() + * | 105: smp_muxed_ipi_set_message(): + * | 105: smb_mb() + * | 105: message[CALL_FUNCTION] = 1 + * | 105: doorbell_global_ipi(42): + * | 105: kvmppc_set_host_ipi(42) + * | // RE-ORDERED STORE COMPLETES + * -> 42: kvmppc_clear_host_ipi(42) + * 42: // returns to executing guest + * 105: ppc_msgsnd_sync()/smp_mb() + * 105: ppc_msgsnd() -> 42 + * 42: local_paca->kvm_hstate.host_ipi == 0 // IPI ignored + * 105: // hangs waiting on 42 to process messages/call_single_queue + */ +static inline void kvmppc_set_host_ipi(int cpu) { - paca_ptrs[cpu]->kvm_hstate.host_ipi = host_ipi; + /* + * order stores of IPI messages vs. setting of host_ipi flag + * + * pairs with the barrier in kvmppc_clear_host_ipi() + */ + smp_mb(); + paca_ptrs[cpu]->kvm_hstate.host_ipi = 1; +} + +static inline void kvmppc_clear_host_ipi(int cpu) +{ + paca_ptrs[cpu]->kvm_hstate.host_ipi = 0; + /* + * order clearing of host_ipi flag vs. processing of IPI messages + * + * pairs with the barrier in kvmppc_set_host_ipi() + */ + smp_mb(); } static inline void kvmppc_fast_vcpu_kick(struct kvm_vcpu *vcpu) @@ -486,7 +577,10 @@ static inline u32 kvmppc_get_xics_latch(void) return 0; } -static inline void kvmppc_set_host_ipi(int cpu, u8 host_ipi) +static inline void kvmppc_set_host_ipi(int cpu) +{} + +static inline void kvmppc_clear_host_ipi(int cpu) {} static inline void kvmppc_fast_vcpu_kick(struct kvm_vcpu *vcpu) diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index ec3714cf0989..b3cbb1136bce 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -475,9 +475,10 @@ #define HMER_DEBUG_TRIG (1ul << (63 - 17)) /* Debug trigger */ #define SPRN_HMEER 0x151 /* Hyp maintenance exception enable reg */ #define SPRN_PCR 0x152 /* Processor compatibility register */ -#define PCR_VEC_DIS (1ul << (63-0)) /* Vec. disable (bit NA since POWER8) */ -#define PCR_VSX_DIS (1ul << (63-1)) /* VSX disable (bit NA since POWER8) */ -#define PCR_TM_DIS (1ul << (63-2)) /* Trans. memory disable (POWER8) */ +#define PCR_VEC_DIS (__MASK(63-0)) /* Vec. disable (bit NA since POWER8) */ +#define PCR_VSX_DIS (__MASK(63-1)) /* VSX disable (bit NA since POWER8) */ +#define PCR_TM_DIS (__MASK(63-2)) /* Trans. memory disable (POWER8) */ +#define PCR_HIGH_BITS (PCR_VEC_DIS | PCR_VSX_DIS | PCR_TM_DIS) /* * These bits are used in the function kvmppc_set_arch_compat() to specify and * determine both the compatibility level which we want to emulate and the @@ -486,6 +487,8 @@ #define PCR_ARCH_207 0x8 /* Architecture 2.07 */ #define PCR_ARCH_206 0x4 /* Architecture 2.06 */ #define PCR_ARCH_205 0x2 /* Architecture 2.05 */ +#define PCR_LOW_BITS (PCR_ARCH_207 | PCR_ARCH_206 | PCR_ARCH_205) +#define PCR_MASK ~(PCR_HIGH_BITS | PCR_LOW_BITS) /* PCR Reserved Bits */ #define SPRN_HEIR 0x153 /* Hypervisor Emulated Instruction Register */ #define SPRN_TLBINDEXR 0x154 /* P7 TLB control register */ #define SPRN_TLBVPNR 0x155 /* P7 TLB control register */ |