Commits on Dec 24, 2019

1. Make HAXM run on system with more than 64 host CPUs …

   Although this patch changed lots of files but only do one thing: make
   HAXM run on system with more than 64 logical CPUs.
   
   Previously, HAX_MAX_CPUS is defined as 64, and HAXM stores CPU online
   bitmap in 64-bit variable. When running on a system with more than 64
   logical CPUs, IPI call actually executed on all CPUs, although internally
   HAXM only maintains a 64-bit bitmap. So some per-CPU routine actually
   runs on different CPUs, but the 64 loop will check the same pair of
   VMXON/VMXOFF for VMX operations, then leads to the error.
   Simply increasing the 64-bit bitmap to larger size may resolve the issue
   but not efficient and clean.
   Previous implementation also has another issue that it invokes
   KeQueryActiveProcessors() to get the total logical CPU number, and
   KeGetCurrentProcessorNumber() to get the current logical CPU ID. However,
   both APIs are NOT designed to get information on Windows with more than
   1 CPU group. Otherwise, both APIs only return value from group 0, which
   can't reveal the actual logical CPU information. Instead, user should use
   KeQueryActiveProcessorCountEx() and KeGetCurrentProcessorNumberEx().
   
   This patch defines the CPU bitmap in 2-dimention way, in unit of group,
   each group can hold up to 64 CPUs for bitmap, same as old implementation.
   And introduce another array to store the per-CPU group/bitmap information
   so that indexing could be fast. This patch also unify cpu init routines,
   more common implementation into same header/source instead of OS specific,
   like cpu_info_init(), smp_cfunction(), smp_call_parameter{}, etc. Since
   they are very fundamental functions, several files are modified.
   
   Change summary:
   - Define 2-dimention structure hax_cpumap_t to store CPU bitmap info.
   Including total group number, total logical CPU number, bitmap within
   each group, group/bit position for each CPU id.
   - For Windows/Linux/Darwin/BSD, use simliar routine cpu_info_init()
   to initialize host CPUs, and implement in OS specific way.
   - On Windows, use KeQueryActiveProcessorCountEx(),
   KeGetCurrentProcessorNumberEx() and KeQueryActiveGroupCount() to get
   correct logical CPUs number and group information, and fill hax_cpumap_t.
   - For Linux/Darwin/BSD, use OS specific routine to get the total logical
   CPU number, and fill into groups consecutive. This is different against
   Windows since logical process group is Windows definition, and CPU bitmap
   is not guaranteed to consecutively fit into a 64-bit bitmap: 64 logical
   CPUs could be in two groups.
   - Implement the new cpu_is_online() function with the new hax_cpumap_t.
   - Implement the new cpu2cpumap() function with the new hax_cpumap_t.
   - Unify OS specific smp_cfunction() implementations in to one, since
   the function is executed by IPI on each CPU, check the CPU online with
   the new cpu_is_online().
   - For all functions refer to the CPU bitmap, use the new implementation.
   - For all per-CPU IPI function, add current CPU id in log.
   
   After this patch, HAXM design won't block running on system with a large
   number CPUs, and easy to expand in case limitted by the date type range:
   now the upper bound is 65536*64 regardless of other resource limitation.
   
   Signed-off-by: Colin Xu <colin.xu@intel.com>

   

   coxuintel committed Dec 24, 2019
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