| config X86 |
| def_bool y |
| |
| config X86_32 |
| def_bool !64BIT |
| |
| config X86_64 |
| def_bool 64BIT |
| |
| menu "x86 Options" |
| |
| config PCI_VERBOSE |
| bool "Verbose PCI Output" |
| default n |
| help |
| Will print out extra information related to PCI. |
| |
| config NOFASTCALL_FSBASE |
| depends on X86_64 |
| bool "Disable fastcall to set FS base" |
| default n |
| help |
| Disable the fast path syscall to set FS base. If your hardware allows |
| setting FS base from userspace, you can say y to disable the fastcall |
| for a slight improvement for all syscalls. If unsure, say n. |
| |
| config FAST_COREID |
| bool "Fast core_id() via rdtscp" |
| default n |
| help |
| Uses rdtscp for a faster core_id() call. Requires a relatively recent |
| microarchitecture (Nehalem). Also, in my experience, qemu's support |
| for rdtscp on some machines is a little lacking, so don't be surprised |
| if it doesn't work when virtualized. Say n if you are unsure. |
| |
| endmenu |
| |
| menu "x86 Hacks" |
| |
| config LOUSY_LAPIC_TIMER |
| bool "Lousy Local APIC Timer" |
| default n |
| help |
| This turns our one-shot APIC timer into a periodic timer. If your |
| system seems to lock up until you hit the keyboard, say 'Y' here and |
| report the results. |
| |
| Qemu without KVM had issues firing a one-shot LAPIC timer (the timer IRQ |
| would only go off when some other IRQ fired), but it worked with a |
| periodic tick. Since we aggressively disarm the timer, this config |
| shouldn't be a performance hit. |
| |
| config NOMTRRS |
| bool "Disable MTRRs" |
| default n |
| help |
| Old debug option from when we were having issues with MTRRs. If your |
| machine won't boot, try turning this on. |
| |
| config ENABLE_MPTABLES |
| bool "Enable MP Tables" |
| default n |
| help |
| Turns on basic MP tables support. If you want to route IRQs, you'll |
| need this, until we get around to parsing ACPI tables. |
| |
| config KB_CORE0_ONLY |
| bool "Keyboard from core0 only" |
| default n |
| help |
| Say 'n' unless you are using a buggy x86 machine that can't handle |
| polling the keyboard PIO from cores other than core 0. |
| |
| config X86_DISABLE_KEYBOARD |
| bool "Disable Keyboard" |
| default n |
| help |
| x86 machines with a legacy USB keyboard often implement the USB stack |
| in SMM mode. When doing anything with the keyboard, including polling |
| the keyboard from the kernel monitor, SMM mode can dramatically |
| interfere with other cores (like a 10-15x performance impact on some |
| benchmarks). |
| |
| Say 'y' if you have such a machine and do not need the keyboard. |
| |
| endmenu |
