diff options
| -rw-r--r-- | arch/powerpc/include/asm/firmware.h | 6 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/kvm_para.h | 26 | ||||
| -rw-r--r-- | arch/powerpc/kernel/Makefile | 5 | ||||
| -rw-r--r-- | arch/powerpc/kernel/firmware.c | 19 | ||||
| -rw-r--r-- | arch/powerpc/platforms/pseries/smp.c | 38 |
5 files changed, 53 insertions, 41 deletions
diff --git a/arch/powerpc/include/asm/firmware.h b/arch/powerpc/include/asm/firmware.h index 6003c2e533a0..f67efbaba17f 100644 --- a/arch/powerpc/include/asm/firmware.h +++ b/arch/powerpc/include/asm/firmware.h @@ -132,6 +132,12 @@ extern int ibm_nmi_interlock_token; extern unsigned int __start___fw_ftr_fixup, __stop___fw_ftr_fixup; +#if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_KVM_GUEST) +bool is_kvm_guest(void); +#else +static inline bool is_kvm_guest(void) { return false; } +#endif + #ifdef CONFIG_PPC_PSERIES void pseries_probe_fw_features(void); #else diff --git a/arch/powerpc/include/asm/kvm_para.h b/arch/powerpc/include/asm/kvm_para.h index 9c1f6b4b9bbf..744612054c94 100644 --- a/arch/powerpc/include/asm/kvm_para.h +++ b/arch/powerpc/include/asm/kvm_para.h @@ -8,35 +8,15 @@ #ifndef __POWERPC_KVM_PARA_H__ #define __POWERPC_KVM_PARA_H__ -#include <uapi/asm/kvm_para.h> - -#ifdef CONFIG_KVM_GUEST - -#include <linux/of.h> - -static inline int kvm_para_available(void) -{ - struct device_node *hyper_node; - - hyper_node = of_find_node_by_path("/hypervisor"); - if (!hyper_node) - return 0; +#include <asm/firmware.h> - if (!of_device_is_compatible(hyper_node, "linux,kvm")) - return 0; - - return 1; -} - -#else +#include <uapi/asm/kvm_para.h> static inline int kvm_para_available(void) { - return 0; + return IS_ENABLED(CONFIG_KVM_GUEST) && is_kvm_guest(); } -#endif - static inline unsigned int kvm_arch_para_features(void) { unsigned long r; diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index c5211bdcf1b6..d4d5946224f8 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -45,11 +45,10 @@ obj-y := cputable.o syscalls.o \ signal.o sysfs.o cacheinfo.o time.o \ prom.o traps.o setup-common.o \ udbg.o misc.o io.o misc_$(BITS).o \ - of_platform.o prom_parse.o + of_platform.o prom_parse.o firmware.o obj-y += ptrace/ obj-$(CONFIG_PPC64) += setup_64.o \ - paca.o nvram_64.o firmware.o note.o \ - syscall_64.o + paca.o nvram_64.o note.o syscall_64.o obj-$(CONFIG_COMPAT) += sys_ppc32.o signal_32.o obj-$(CONFIG_VDSO32) += vdso32/ obj-$(CONFIG_PPC_WATCHDOG) += watchdog.o diff --git a/arch/powerpc/kernel/firmware.c b/arch/powerpc/kernel/firmware.c index cc4a5e3f51f1..fe48d319d490 100644 --- a/arch/powerpc/kernel/firmware.c +++ b/arch/powerpc/kernel/firmware.c @@ -11,8 +11,27 @@ #include <linux/export.h> #include <linux/cache.h> +#include <linux/of.h> #include <asm/firmware.h> +#ifdef CONFIG_PPC64 unsigned long powerpc_firmware_features __read_mostly; EXPORT_SYMBOL_GPL(powerpc_firmware_features); +#endif + +#if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_KVM_GUEST) +bool is_kvm_guest(void) +{ + struct device_node *hyper_node; + + hyper_node = of_find_node_by_path("/hypervisor"); + if (!hyper_node) + return 0; + + if (!of_device_is_compatible(hyper_node, "linux,kvm")) + return 0; + + return 1; +} +#endif diff --git a/arch/powerpc/platforms/pseries/smp.c b/arch/powerpc/platforms/pseries/smp.c index a1cb861154e9..92922491a81c 100644 --- a/arch/powerpc/platforms/pseries/smp.c +++ b/arch/powerpc/platforms/pseries/smp.c @@ -210,24 +210,32 @@ static __init void pSeries_smp_probe(void) if (!cpu_has_feature(CPU_FTR_SMT)) return; - /* - * KVM emulates doorbells by disabling FSCR[MSGP] so msgsndp faults - * to the hypervisor which then reads the instruction from guest - * memory. This can't be done if the guest is secure, so don't use - * doorbells in secure guests. - * - * Under PowerVM, FSCR[MSGP] is enabled so doorbells could be used - * by secure guests if we distinguished this from KVM. - */ - if (is_secure_guest()) - return; + if (is_kvm_guest()) { + /* + * KVM emulates doorbells by disabling FSCR[MSGP] so msgsndp + * faults to the hypervisor which then reads the instruction + * from guest memory, which tends to be slower than using XIVE. + */ + if (xive_enabled()) + return; + + /* + * XICS hcalls aren't as fast, so we can use msgsndp (which + * also helps exercise KVM emulation), however KVM can't + * emulate secure guests because it can't read the instruction + * out of their memory. + */ + if (is_secure_guest()) + return; + } /* - * The guest can use doobells for SMT sibling IPIs, which stay in - * the core rather than going to the interrupt controller. This - * tends to be slower under KVM where doorbells are emulated, but - * faster for PowerVM where they're enabled. + * Under PowerVM, FSCR[MSGP] is enabled as guest vCPU siblings are + * gang scheduled on the same physical core, so doorbells are always + * faster than the interrupt controller, and they can be used by + * secure guests. */ + ic_cause_ipi = smp_ops->cause_ipi; smp_ops->cause_ipi = dbell_or_ic_cause_ipi; } |