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| author | Keir Fraser <keir.fraser@citrix.com> | 2008-09-22 13:46:57 +0100 |
|---|---|---|
| committer | Keir Fraser <keir.fraser@citrix.com> | 2008-09-22 13:46:57 +0100 |
| commit | a0c61c0f77d2e0926bf728623e474fe9126648ae (patch) | |
| tree | 1ed061a7b59d162a5b33b11ea9dfc38e95fe28f3 /xen/arch/x86/boot | |
| parent | 27e019d758f4aa3cdbae469fb9c2fada5a021cfa (diff) | |
| download | xen-a0c61c0f77d2e0926bf728623e474fe9126648ae.tar.gz xen-a0c61c0f77d2e0926bf728623e474fe9126648ae.tar.bz2 xen-a0c61c0f77d2e0926bf728623e474fe9126648ae.zip | |
x86: make GDT per-CPU
The major issue with supporting a significantly larger number of
physical CPUs appears to be the use of per-CPU GDT entries - at
present, x86-64 could support only up to 126 CPUs (with code changes
to also use the top-most GDT page, that would be 254). Instead of
trying to go with incremental steps here, by converting the GDT itself
to be per-CPU, limitations in that respect go away entirely.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Diffstat (limited to 'xen/arch/x86/boot')
| -rw-r--r-- | xen/arch/x86/boot/wakeup.S | 2 | ||||
| -rw-r--r-- | xen/arch/x86/boot/x86_32.S | 6 | ||||
| -rw-r--r-- | xen/arch/x86/boot/x86_64.S | 10 |
3 files changed, 12 insertions, 6 deletions
diff --git a/xen/arch/x86/boot/wakeup.S b/xen/arch/x86/boot/wakeup.S index 502f510102..cc4cda556a 100644 --- a/xen/arch/x86/boot/wakeup.S +++ b/xen/arch/x86/boot/wakeup.S @@ -168,7 +168,7 @@ wakeup_32: .word 0,0,0 lgdt_descr: .word LAST_RESERVED_GDT_BYTE - .quad gdt_table - FIRST_RESERVED_GDT_BYTE + .quad boot_cpu_gdt_table - FIRST_RESERVED_GDT_BYTE wakeup_64: lgdt lgdt_descr(%rip) diff --git a/xen/arch/x86/boot/x86_32.S b/xen/arch/x86/boot/x86_32.S index 5e29e4d7ea..2cabb18cf3 100644 --- a/xen/arch/x86/boot/x86_32.S +++ b/xen/arch/x86/boot/x86_32.S @@ -78,7 +78,7 @@ idt_descr: .word 0 gdt_descr: .word LAST_RESERVED_GDT_BYTE - .long gdt_table - FIRST_RESERVED_GDT_BYTE + .long boot_cpu_gdt_table - FIRST_RESERVED_GDT_BYTE .align 32 @@ -94,7 +94,7 @@ ENTRY(idle_pg_table) #define GUEST_DESC(d) \ .long ((MACH2PHYS_VIRT_END - 1) >> 12) & 0xffff, \ ((MACH2PHYS_VIRT_END - 1) >> 12) & (0xf << 16) | (d) -ENTRY(gdt_table) +ENTRY(boot_cpu_gdt_table) .quad 0x0000000000000000 /* unused */ .quad 0x00cf9a000000ffff /* 0xe008 ring 0 4.00GB code at 0x0 */ .quad 0x00cf92000000ffff /* 0xe010 ring 0 4.00GB data at 0x0 */ @@ -102,4 +102,6 @@ ENTRY(gdt_table) GUEST_DESC(0x00c0b200) /* 0xe021 ring 1 3.xxGB data at 0x0 */ GUEST_DESC(0x00c0fa00) /* 0xe02b ring 3 3.xxGB code at 0x0 */ GUEST_DESC(0x00c0f200) /* 0xe033 ring 3 3.xxGB data at 0x0 */ + .fill (PER_CPU_GDT_ENTRY - FLAT_RING3_DS / 8 - 1), 8, 0 + .quad 0x0000910000000000 /* per-CPU entry (limit == cpu) */ .align PAGE_SIZE,0 diff --git a/xen/arch/x86/boot/x86_64.S b/xen/arch/x86/boot/x86_64.S index 07756e9024..7932f8aaa9 100644 --- a/xen/arch/x86/boot/x86_64.S +++ b/xen/arch/x86/boot/x86_64.S @@ -85,7 +85,7 @@ multiboot_ptr: .word 0 gdt_descr: .word LAST_RESERVED_GDT_BYTE - .quad gdt_table - FIRST_RESERVED_GDT_BYTE + .quad boot_cpu_gdt_table - FIRST_RESERVED_GDT_BYTE .word 0,0,0 idt_descr: @@ -96,7 +96,7 @@ ENTRY(stack_start) .quad cpu0_stack .align PAGE_SIZE, 0 -ENTRY(gdt_table) +ENTRY(boot_cpu_gdt_table) .quad 0x0000000000000000 /* unused */ .quad 0x00af9a000000ffff /* 0xe008 ring 0 code, 64-bit mode */ .quad 0x00cf92000000ffff /* 0xe010 ring 0 data */ @@ -105,11 +105,13 @@ ENTRY(gdt_table) .quad 0x00cff2000000ffff /* 0xe02b ring 3 data */ .quad 0x00affa000000ffff /* 0xe033 ring 3 code, 64-bit mode */ .quad 0x00cf9a000000ffff /* 0xe038 ring 0 code, compatibility */ + .fill (PER_CPU_GDT_ENTRY - __HYPERVISOR_CS32 / 8 - 1), 8, 0 + .quad 0x0000910000000000 /* per-CPU entry (limit == cpu) */ .align PAGE_SIZE, 0 /* NB. Even rings != 0 get access to the full 4Gb, as only the */ /* (compatibility) machine->physical mapping table lives there. */ -ENTRY(compat_gdt_table) +ENTRY(boot_cpu_compat_gdt_table) .quad 0x0000000000000000 /* unused */ .quad 0x00af9a000000ffff /* 0xe008 ring 0 code, 64-bit mode */ .quad 0x00cf92000000ffff /* 0xe010 ring 0 data */ @@ -118,4 +120,6 @@ ENTRY(compat_gdt_table) .quad 0x00cffa000000ffff /* 0xe02b ring 3 code, compatibility */ .quad 0x00cff2000000ffff /* 0xe033 ring 3 data */ .quad 0x00cf9a000000ffff /* 0xe038 ring 0 code, compatibility */ + .fill (PER_CPU_GDT_ENTRY - __HYPERVISOR_CS32 / 8 - 1), 8, 0 + .quad 0x0000910000000000 /* per-CPU entry (limit == cpu) */ .align PAGE_SIZE, 0 |