KVM: emulate: protect checks on ctxt->d by a common "if (unlikely())"

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There are several checks for "peculiar" aspects of instructions in both
x86_decode_insn and x86_emulate_insn.  Group them together, and guard
them with a single "if" that lets the processor quickly skip them all.
Make this more effective by adding two more flag bits that say whether the
.intercept and .check_perm fields are valid.  We will reuse these
flags later to avoid initializing fields of the emulate_ctxt struct.

This skims about 30 cycles for each emulated instructions, which is
approximately a 3% improvement.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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Paolo Bonzini 2014-03-27 11:58:02 +01:00

parent e24186e097

commit d40a6898e5

1 changed files with 94 additions and 81 deletions

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arch/x86/kvm/emulate.c

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