similar to: [RFC/PATCH PV_OPS X86_64 07/17] paravirt_ops - descriptor changes.

Hi all, I've been working on a port of paravirt_ops for the x86_64 architectures for a couple of days. Here's the result so far. I'm posting it soon for early cooments. The more, the better. It's obviously based on the previous work for i386, with the needed modifications. By now, I'm able to boot a bare metal kernel, but there are still some known issues, that are in my TODO

Hi all, I've been working on a port of paravirt_ops for the x86_64 architectures for a couple of days. Here's the result so far. I'm posting it soon for early cooments. The more, the better. It's obviously based on the previous work for i386, with the needed modifications. By now, I'm able to boot a bare metal kernel, but there are still some known issues, that are in my TODO

Big cleanup of LDT code. This code has very little type checking and is not frequently used, so I audited the code, added type checking and size optimizations to generate smaller assembly code. I changed the ldt count to be in pages, and converted the char * ldt into a desc_struct. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.14-zach-work/arch/i386/kernel/ldt.c

Big cleanup of LDT code. This code has very little type checking and is not frequently used, so I audited the code, added type checking and size optimizations to generate smaller assembly code. I changed the ldt count to be in pages, and converted the char * ldt into a desc_struct. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.14-zach-work/arch/i386/kernel/ldt.c

Hi, this is a series of patches that unify the struct desc_struct and friends across x86_64 and i386. As usual, it provides paravirt capabilities as a side-effect for x86_64. I consider the main goal, namely, of unifying the desc_struct, an ongoing effort, being this the beginning. A lot of old code has to be touched to accomplish that. I don't consider this patch ready for inclusion.

Hi, this is a series of patches that unify the struct desc_struct and friends across x86_64 and i386. As usual, it provides paravirt capabilities as a side-effect for x86_64. I consider the main goal, namely, of unifying the desc_struct, an ongoing effort, being this the beginning. A lot of old code has to be touched to accomplish that. I don't consider this patch ready for inclusion.

By Andi Kleen's suggestion, this patch removes pack_ldt() and pack_tss() wrappers in favour of a general wrapper. It saves us an ifdef and some lines of code, but more importantly, it's more elegant. No functional change is made. Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> --- include/asm-x86/desc.h | 55 ++++++++++++++--------------------------------- 1 files

By Andi Kleen's suggestion, this patch removes pack_ldt() and pack_tss() wrappers in favour of a general wrapper. It saves us an ifdef and some lines of code, but more importantly, it's more elegant. No functional change is made. Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> --- include/asm-x86/desc.h | 55 ++++++++++++++--------------------------------- 1 files

i386 Transparent paravirtualization subarch patch #5 This change encapsulates descriptor and task register management. Diffs against: 2.6.13-rc4-mm1 Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/desc.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/desc.h 2005-08-08 17:31:59.000000000 -0700

i386 Transparent paravirtualization subarch patch #5 This change encapsulates descriptor and task register management. Diffs against: 2.6.13-rc4-mm1 Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/desc.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/desc.h 2005-08-08 17:31:59.000000000 -0700

* zach@vmware.com (zach@vmware.com) wrote: > Make the LDT a desc_struct pointer, since this is what it actually is. I like that plan. > There is code which relies on the fact that LDTs are allocated in page > chunks, and it is both cleaner and more convenient to keep the rather > poorly named "size" variable from the LDT in terms of LDT pages. I noticed it's replaced

* zach@vmware.com (zach@vmware.com) wrote: > Make the LDT a desc_struct pointer, since this is what it actually is. I like that plan. > There is code which relies on the fact that LDTs are allocated in page > chunks, and it is both cleaner and more convenient to keep the rather > poorly named "size" variable from the LDT in terms of LDT pages. I noticed it's replaced

By moving init_new_context and destroy_context inline into mmu_context.h, we can avoid extra functions calls, which are only needed for the unlikely case that the process context has an LDT to deal with. Now the code in ldt.c is called only when actually dealing with LDT creation or destruction. Careful analysis of alloc_ldt function showed that by using two const parameters, huge amounts of

By moving init_new_context and destroy_context inline into mmu_context.h, we can avoid extra functions calls, which are only needed for the unlikely case that the process context has an LDT to deal with. Now the code in ldt.c is called only when actually dealing with LDT creation or destruction. Careful analysis of alloc_ldt function showed that by using two const parameters, huge amounts of

Add an acessor function to get a pointer to an LDT descriptor. Add one for the GDT too, while we are here, and a function to tell the difference. Turns out on some GCC versions, converting to char * and back gives better code output than gdt[seg >> 3]. Lets keep that trick in the header file so the C-code can be clean. Not used yet, but soon. Signed-off-by: Zachary Amsden

Add an acessor function to get a pointer to an LDT descriptor. Add one for the GDT too, while we are here, and a function to tell the difference. Turns out on some GCC versions, converting to char * and back gives better code output than gdt[seg >> 3]. Lets keep that trick in the header file so the C-code can be clean. Not used yet, but soon. Signed-off-by: Zachary Amsden

Descriptor and trap table cleanups. Add cleanly written accessors for IDT and GDT gates so the subarch may override them. Note that this allows the hypervisor to transparently tweak the DPL of the descriptors as well as the RPL of segments in those descriptors, with no unnecessary kernel code modification. It also allows the hypervisor implementation of the VMI to tweak the gates, allowing for

Descriptor and trap table cleanups. Add cleanly written accessors for IDT and GDT gates so the subarch may override them. Note that this allows the hypervisor to transparently tweak the DPL of the descriptors as well as the RPL of segments in those descriptors, with no unnecessary kernel code modification. It also allows the hypervisor implementation of the VMI to tweak the gates, allowing for

Make GDT page aligned and page padded to support running inside of a hypervisor. This prevents false sharing of the GDT page with other hot data, which is not allowed in Xen, and causes performance problems in VMware. Rather than go back to the old method of statically allocating the GDT (which wastes unneded space for non-present CPUs), the GDT for APs is allocated dynamically. Signed-off-by:

Make GDT page aligned and page padded to support running inside of a hypervisor. This prevents false sharing of the GDT page with other hot data, which is not allowed in Xen, and causes performance problems in VMware. Rather than go back to the old method of statically allocating the GDT (which wastes unneded space for non-present CPUs), the GDT for APs is allocated dynamically. Signed-off-by: