Andre Przywara
2010-Sep-16 13:04 UTC
[Xen-devel] [PATCH 0/5 -v3] xl: add cpuid config file option
Hi, again an updated version of the patch series to introduce a cpuid parameter in xl. Changes from v2: - fix the IDL part to use pass-by-reference and to make the type opaque - use strtok_r instead of strtok to avoid interference with other strtoks. - fix 3DNow bit numbers (swapped 3dnow and 3dnowext) - fix bug with cpuid="" - fix bug with comparison of flag names - make one error message more verbose Hope that this is the final version. Regards, Andre. -------------- xl is currently ignoring the cpuid= variable in the config file. As I don''t like the current interface xm exposes (basically because it is complicated, unintuitive and very error prone), I implemented a new scheme for specifying CPUID flags policy, combining QEMU''s and Xen''s approach: cpuid = "<base>,<feature_name>=[01xks]*,... The patch includes a (preliminary) list of feature names along with their bit positions. The value for each feature bit copies the current meaning is Xen: 0: clear, 1: set, x: don''t care/use default, k: keep from host, s: use host but preserve across migration The value can also be a number (either in hex or decimal), so things like "stepping=3" can be easily specified. To show you the advantage, I quote the example config file: > #cpuid=[ ''1:ecx=xxxxxxxxxxx00xxxxxxxxxxxxxxxxxxx, > # eax=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'' ] > # - Unset the SSE4 features (CPUID.1[ECX][20-19]) > # - Default behaviour for all other bits in ECX And EAX registers. new version: cpuid = "host,sse4.1=0,sse4.2=0" > # Expose to the guest multi-core cpu instead of multiple processors > # Example for intel, expose a 8-core processor : > #cpuid=[''1:edx=xxx1xxxxxxxxxxxxxxxxxxxxxxxxxxxx, > # ebx=xxxxxxxx00010000xxxxxxxxxxxxxxxx'', > # ''4,0:eax=001111xxxxxxxxxxxxxxxxxxxxxxxxxx''] > # - CPUID.1[EDX][HT] : Enable HT > # - CPUID.1[EBX] : Number of vcpus * 2 > # - CPUID.4,0[EAX] : Number of vcpus * 2 - 1 > #vcpus=8 new version: cpuid = "host,htt=1,proccount=16,maxcores=15" > # Example for amd, expose a 5-core processor : > # cpuid = [''1:ebx=xxxxxxxx00001010xxxxxxxxxxxxxxxx, > # edx=xxx1xxxxxxxxxxxxxxxxxxxxxxxxxxxx'', > # ''0x80000001:ecx=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx1x'', > # ''0x80000008:ecx=xxxxxxxxxxxxxxxxxxxxxxxxxx001001''] > # - CPUID.1[EBX] : Threads per Core * Cores per Socket (2 * #vcpus) > # - CPUID.1[EDX][HT] : Enable HT > # - CPUID.0x80000001[CmpLegacy] : Use legacy method > # - CPUID.0x80000008[ECX] : #vcpus * 2 - 1 new version: cpuid="host,htt=1,cmplegacy=1,proccount=10,nc=9" -- Andre Przywara AMD-Operating System Research Center (OSRC), Dresden, Germany Tel: +49 351 448-3567-12 _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel