Shared caches in multi-core CPU architectures represent a problem for predictability of memory access latency. This jeopardizes applicability of many Arm platform in real-time critical and mixed-criticality scenarios. We introduce support for cache partitioning with page coloring, a transparent software technique that enables isolation between domains and Xen, and thus avoids cache interference.
When creating a domain, a simple syntax (e.g. `0-3` or `4-11`) allows the user to define assignments of cache partitions ids, called colors, where assigning different colors guarantees no mutual eviction on cache will ever happen. This instructs the Xen memory allocator to provide the i-th color assignee only with pages that maps to color i, i.e. that are indexed in the i-th cache partition. The proposed implementation supports the dom0less feature. The proposed implementation doesn't support the static-mem feature. The solution has been tested in several scenarios, including Xilinx Zynq MPSoCs. In this patch series there are two major unacceptable workarounds for which I want to ask you for comments: - #3: allocate_memory() has been moved in dom0less_build.c, so I just copied it back to make it compile. - #13: consider_modules() has been moved to arm32 only. Again I just copied it. Carlo Nonato (12): xen/common: add cache coloring common code xen/arm: add cache coloring initialization xen/arm: add Dom0 cache coloring support xen: extend domctl interface for cache coloring tools: add support for cache coloring configuration xen/arm: add support for cache coloring configuration via device-tree xen/page_alloc: introduce init_free_page_fields() helper xen/page_alloc: introduce preserved page flags macro xen: add cache coloring allocator for domains xen/arm: use domain memory to allocate p2m page tables Revert "xen/arm: Remove unused BOOT_RELOC_VIRT_START" xen/arm: add cache coloring support for Xen Luca Miccio (1): xen/arm: add Xen cache colors command line parameter docs/man/xl.cfg.5.pod.in | 10 + docs/misc/arm/cache-coloring.rst | 209 ++++++++++++ docs/misc/arm/device-tree/booting.txt | 4 + docs/misc/xen-command-line.pandoc | 61 ++++ tools/include/libxl.h | 5 + tools/include/xenctrl.h | 9 + tools/libs/ctrl/xc_domain.c | 34 ++ tools/libs/light/libxl_create.c | 9 + tools/libs/light/libxl_types.idl | 1 + tools/xl/xl_parse.c | 38 ++- xen/arch/Kconfig | 28 ++ xen/arch/arm/Kconfig | 1 + xen/arch/arm/Makefile | 1 + xen/arch/arm/alternative.c | 9 +- xen/arch/arm/arm64/mmu/head.S | 48 +++ xen/arch/arm/arm64/mmu/mm.c | 26 +- xen/arch/arm/dom0less-build.c | 19 ++ xen/arch/arm/domain_build.c | 60 +++- xen/arch/arm/include/asm/llc-coloring.h | 46 +++ xen/arch/arm/include/asm/mm.h | 12 +- xen/arch/arm/include/asm/mmu/layout.h | 2 + xen/arch/arm/include/asm/processor.h | 16 + xen/arch/arm/llc-coloring.c | 409 ++++++++++++++++++++++++ xen/arch/arm/mmu/p2m.c | 4 +- xen/arch/arm/mmu/setup.c | 83 ++++- xen/arch/arm/mmu/smpboot.c | 11 +- xen/arch/arm/psci.c | 9 +- xen/arch/arm/setup.c | 172 +++++++++- xen/arch/arm/smpboot.c | 9 +- xen/common/Kconfig | 3 + xen/common/domain.c | 4 + xen/common/domctl.c | 11 + xen/common/keyhandler.c | 4 + xen/common/page_alloc.c | 217 ++++++++++++- xen/include/public/domctl.h | 10 +- xen/include/xen/llc-coloring.h | 53 +++ xen/include/xen/sched.h | 5 + 37 files changed, 1610 insertions(+), 42 deletions(-) create mode 100644 docs/misc/arm/cache-coloring.rst create mode 100644 xen/arch/arm/include/asm/llc-coloring.h create mode 100644 xen/arch/arm/llc-coloring.c create mode 100644 xen/include/xen/llc-coloring.h -- 2.34.1
