similar to: [PATCH 5/10] Paravirt kmap_atomic_pte tidy.patch

In shadow mode hypervisors, ptep_get_and_clear achieves the desired purpose of keeping the shadows in sync by issuing a native_get_and_clear, followed by a call to pte_update, which indicates the PTE has been modified. Direct mode hypervisors (Xen) have no need for this anyway, and will trap the update using writable pagetables. This means no hypervisor makes use of ptep_get_and_clear; there is

In shadow mode hypervisors, ptep_get_and_clear achieves the desired purpose of keeping the shadows in sync by issuing a native_get_and_clear, followed by a call to pte_update, which indicates the PTE has been modified. Direct mode hypervisors (Xen) have no need for this anyway, and will trap the update using writable pagetables. This means no hypervisor makes use of ptep_get_and_clear; there is

Implement vmi_kmap_atomic_pte in terms of the backend set_linear_mapping operation. The conversion is rather straighforward; call kmap_atomic and then inform the hypervisor of the page mapping. The _flush_tlb damage is due to macros being pulled in from highmem.h. Signed-off-by: Zachary Amsden <zach@vmware.com> diff -r 2207a31829e7 arch/i386/kernel/vmi.c --- a/arch/i386/kernel/vmi.c Mon

Implement vmi_kmap_atomic_pte in terms of the backend set_linear_mapping operation. The conversion is rather straighforward; call kmap_atomic and then inform the hypervisor of the page mapping. The _flush_tlb damage is due to macros being pulled in from highmem.h. Signed-off-by: Zachary Amsden <zach@vmware.com> diff -r 2207a31829e7 arch/i386/kernel/vmi.c --- a/arch/i386/kernel/vmi.c Mon

[ I think this is a straight repost this patch, which addresses all the previous comments. I'd like to submit this for .24 as the basis for a unified paravirt_ops. Any objections? ] This patch refactors the paravirt_ops structure into groups of functionally related ops: pv_info - random info, rather than function entrypoints pv_init_ops - functions used at boot time (some for module_init

[ I think this is a straight repost this patch, which addresses all the previous comments. I'd like to submit this for .24 as the basis for a unified paravirt_ops. Any objections? ] This patch refactors the paravirt_ops structure into groups of functionally related ops: pv_info - random info, rather than function entrypoints pv_init_ops - functions used at boot time (some for module_init

This patch refactors the paravirt_ops structure into groups of functionally related ops: pv_info - random info, rather than function entrypoints pv_init_ops - functions used at boot time (some for module_init too) pv_misc_ops - lazy mode, which didn't fit well anywhere else pv_time_ops - time-related functions pv_cpu_ops - various privileged instruction ops pv_irq_ops - operations for

This patch refactors the paravirt_ops structure into groups of functionally related ops: pv_info - random info, rather than function entrypoints pv_init_ops - functions used at boot time (some for module_init too) pv_misc_ops - lazy mode, which didn't fit well anywhere else pv_time_ops - time-related functions pv_cpu_ops - various privileged instruction ops pv_irq_ops - operations for

Here's a first attempt at splitting up paravirt_ops into more specific chunks. Its pretty clunky and chunky; mostly just a lot of replacement. The grouping of ops is very first cut; I'm open to suggestions about what groups should exist and what ops they each should contain. The only slightly subtle part is that I've kept the structures wrapped in a paravirt_ops structure,

Here's a first attempt at splitting up paravirt_ops into more specific chunks. Its pretty clunky and chunky; mostly just a lot of replacement. The grouping of ops is very first cut; I'm open to suggestions about what groups should exist and what ops they each should contain. The only slightly subtle part is that I've kept the structures wrapped in a paravirt_ops structure,

While, as discussed, the performance impact of this option is certainly higher than on native Linux, the option should not be entirely disallowed if people want to sacrifice performance for less lowmem pressure. Signed-off-by: Jan Beulich <jbeulich@novell.com> Index: sle10-sp1-2007-01-10/arch/i386/Kconfig =================================================================== ---

Create a new PTE function which combines clearing a kernel PTE with the subsequent flush. This allows the two to be easily combined into a single hypercall or paravirt-op. More subtly, reverse the order of the flush for kmap_atomic. Instead of flushing on establishing a mapping, flush on clearing a mapping. This eliminates the possibility of leaving stale kmap entries which may still have

MMU code movement. Unfortunately, this one is a little bit more complicated than the rest. We have to override the default accessors that directly write to page table entries. Because of the 2/3-level PAE split in Linux, this turned out to be really ugly at first, but by allowing the sub-arch layer to override the definitions and keeping the native definitions in place, the code becomes much

MMU code movement. Unfortunately, this one is a little bit more complicated than the rest. We have to override the default accessors that directly write to page table entries. Because of the 2/3-level PAE split in Linux, this turned out to be really ugly at first, but by allowing the sub-arch layer to override the definitions and keeping the native definitions in place, the code becomes much

[ I think this is a straight repost this patch, which addresses all the previous comments. I'd like to submit this for .24 as the basis for a unified paravirt_ops. Any objections? ] Currently, the set_lazy_mode pv_op is overloaded with 5 functions: 1. enter lazy cpu mode 2. leave lazy cpu mode 3. enter lazy mmu mode 4. leave lazy mmu mode 5. flush pending batched operations This

[ I think this is a straight repost this patch, which addresses all the previous comments. I'd like to submit this for .24 as the basis for a unified paravirt_ops. Any objections? ] Currently, the set_lazy_mode pv_op is overloaded with 5 functions: 1. enter lazy cpu mode 2. leave lazy cpu mode 3. enter lazy mmu mode 4. leave lazy mmu mode 5. flush pending batched operations This

Assumes hypervisor interface headers have been sync-ed after the hypervisor side patch was applied. As usual, written and tested on 2.6.27.3 and made apply to the 2.6.18 tree without further testing. Signed-off-by: Jan Beulich <jbeulich@novell.com> Index: head-2008-10-24/arch/i386/mm/highmem-xen.c =================================================================== ---

Provide a PT map hook for HIGHPTE kernels to designate where they are mapping page tables. This information is required so the physical address of PTE updates can be determined; otherwise, the mm layer would have to carry the physical address all the way to each PTE modification callsite, which is even more hideous that the macros required to provide the proper hooks. So lets not mess up arch

Provide a PT map hook for HIGHPTE kernels to designate where they are mapping page tables. This information is required so the physical address of PTE updates can be determined; otherwise, the mm layer would have to carry the physical address all the way to each PTE modification callsite, which is even more hideous that the macros required to provide the proper hooks. So lets not mess up arch

Currently, the set_lazy_mode pv_op is overloaded with 5 functions: 1. enter lazy cpu mode 2. leave lazy cpu mode 3. enter lazy mmu mode 4. leave lazy mmu mode 5. flush pending batched operations This complicates each paravirt backend, since it needs to deal with all the possible state transitions, handling flushing, etc. In particular, flushing is quite distinct from the other 4 functions,